Category Archives: Technology

Runway 9-27 : The Road to SEMA

The 1650 Ultima GTR at rest on runway 9-27. Photo Credit: John Erlien - Mercury Marine.
The 1650 Ultima GTR at rest on runway 9-27. Photo Credit: Jon Erlien – Mercury Marine.

We’re back in Las Vegas for the 2014 Specialty Equipment Market Association (SEMA) show. It’s hard to believe a year has passed since we unveiled our QC4v automotive crate engine here.  Since then – we’ve received a lot of interest in the product and its capabilities. Various applications have been suggested – off road racing, drag racing and high performance street rods to name a few.   Read more

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Hush the Magic 520!

The 520 sterndrive comes with cast iron manifolds with stainless steel exhaust elbows.
The 520 sterndrive comes with cast iron manifolds with stainless steel exhaust elbows.
Mercury Racing 520s with Axius Joystick Piloting technology is a popular option for their 400FX Sport Cruiser.
The 520 with Axius Joystick Piloting technology is a popular option for Formula’s 400FX Sport Cruiser.

Our new 520 sterndrive has been a resounding success since it was introduced one year ago at  the LOTO (Lake of the Ozarks) Shootout. It’s become even more popular since the release of a  Joystick Piloting for Sterndrives – Axius option for selected models fitted with the Bravo Three XR sterndrive. Formula boats have been early adopters of the engine package. They are also the first OEM boat builder to install the potent engines with joystick control. A Formula 400FX used to demonstrate joystick 520 maneuvers at the Miami Boat Show had standard through transom exhaust fitted with aftermarket mufflers. For our traditional sport boat crowd – they had a nice exhaust note. For those looking for enhanced performance without all the rumble – it might have been a bit much.

Alpha maleness without all the barking!
Alpha maleness without all the barking!
This CAD drawing shows the the port and starboard exhaust connected by a custom y-pipe.
This CAD drawing shows a 520 engine fitted with the starboard X-haust Noise Reducer System – Stage 1.

We took note, no pun intended, and went to work to create an X-haust Noise Reduction system designed specifically for the 520.  The system will appease our friends at Formula and a variety of our OEM boat builder partners, dealers and consumers looking to take advantage of the 520’s performance value.  It will also be adopted in European Union countries where the engine is certified in meeting the stringent RCD (Recreational Craft Directive) exhaust emissions standards. Read more

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Got Wheels?

An electronic file of the SEMA brochure.
An electronic file of the SEMA brochure.
The QC4v crate engine shares attributes of its marine cousins.
The QC4v crate engine shares attributes of its marine cousins.

We are excited to unveil our concept QC4v crate engine this week at the 50th annual SEMA show. The A multitude of configurations are possible, fom basic long block form to ready to run engines.  The project has to be one of our best kept secrets ever.

QC4v in the tightly confined engine bay a mid-engine two-seater.
QC4v in the tightly confined engine bay a mid-engine two-seater.

This is our first  SEMA show and there is a lot to see. We brought  an exotic supercar fitted with a turbocharged QC4v 1650 crate engine. The car is complimented with an equally exotic DCB M41-Wide Body catamaran sport boat powered by twin 1350 sterndrives.

The brilliant  QC4v crate engine cutaway.
The brilliant QC4v crate engine cutaway.

An  immaculate cutaway crate engine display shows the brilliantly engineered inner workings of the QC4v engine design. That is flanked by a complete QC4v 1350 and 8.2 Liter 520 sterndrive engine displays. A complete QC4v crate engine is featured in SEMA’s New Products Showcase. Read more

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CLEAN POWER FOR THE EUROPEAN UNION

This is the 5th in a series on design features of Mercury Racing’s  Quad Cam, four valve sterndrive engine.

The heart of our turbo compressor: hot gas expands through turbine blades, while at the other end of the shaft, compressor blades pack air into the inlet plenum.
Imagine the pulse rate in this triple 1350 powered Cigarette Marauder!

As I mentioned in The Valve Train That Could, valves exist to get air in and exhaust out. Well, the exhaust isn’t finished just because it’s past the intake valves. It’s got work to do: It’s time to “Peg the fun-o-meter” for some lucky boater! Exhaust heat remains from combustion. All turbocharged engines use that “waste” energy to spin a turbine, compressing incoming air to higher density. QC4v does that – and more.

It’s less commonly known (except by header designers and a few other social deviants), the exhaust flow also has pressure waves racing down and back up the exhaust system. When an exhaust valve opens to expel spent combustion gases, the rapid pressure rise sends a pulse down the pipe at the speed of sound. Read more

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Erik’s Reality

The all-new 1650 RACE features closed cooled turbochagers.
The all-new 1650 RACE features closed cooled turbochagers.
The 1350 is no longer the fastest or strongest in Racing's H.P. stable.
The 1350 is no longer the fastest or strongest in Racing’s H.P. stable.

It’s hard to believe a year has passed and the 2013 Miami Boat Show is underway. We’ve experienced some major events since our last visit to South Beach. Fred Kiekhaefer has moved on after 22 years of service. With Fred’s departure, Erik Christiansen has been named General Manager. Fred will continue to represent Mercury Racing over the next two years. In fact, he’s at the show. If your there, be sure to stop by the Mercury booth and say hello. Erik and our staff of sales, service and engineering personnel are there to support the brand as well.

I decided to forgo the show this year to be with my son. I’ll miss seeing everyone and the exciting new products being unveiled. Jay Nichols has ensured me he will keep me abreast of the action via his acclaimed photography.

Rumor Mill

The 1650 RACE features reversed colors from the std. 1350 offering.
The 1650 RACE features reversed colors from the std. 1350 offering.

Some of you may be aware of the rumor mill started a while back when Powerboat Nation posted a story speculating we were going to release a 1700 h.p. engine. The story featured a dated 1350 model shot. Erik squashed all rumors when he unveiled the all-new 1650 RACE sterndrive. Based on our exclusive quad cam, four valve 1350, this monster features new pistons, larger turbos and requires 112 AKI race fuel.

So there, PB Nation. You were correct in that – yes – we did release a higher power engine based on our exclusive quad cam, four valve engine platform. You were off on the power and color, however. And no, this is not your father’s poker run engine. It is a race engine that is sold, without warranty, to qualified powerboat racing professionals. I’ll make sure you get a press kit:) Read more

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Key West Poker Run Recap

The QC4v 1350 sterndrive always draws a crowd.
Mercury Racing was recognized for our title sponsorship at the Friday Night sponsor party.

Whew! I’m just getting back to a “normal” schedule after last week’s Key West Poker Run. It was a great event. We had people at the Mercury Racing truck from the moment we unloaded our 1350 and 565 display engines through the 10:00 p.m. closing time. It was non-stop action Thursday through Saturday. It’s always fun to meet and greet folks who enjoy our products. It is equally enjoyable to establish new relationships with future customers.

This year was the 20th anniversary of the event. Stu Jones and the Florida Powerboat Club staff didn’t disappoint. This has to be the largest gathering of performance boats on earth. It is also the largest gathering of performance boat builders and dealers. Industry movers and shakers included Reggie Fountain, Randy Scism (MTI), Peter Hledin (Skater), Chad Braver (Cigarette), Todd Warner (Statement), Nils Johnson and Trond Schou (Nor-Tech), Paul Loguidice (Hustler), David Woods and Scott Shogren (Pier 57). Read more

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565: How’d We Do That – Part 2?

Mercury Racing’s dynos enable precise calibration by our exceptionally talented engineering techs, like Johnny Bauer. They also validate that every production 565 meets its targets.

Mercury Racing’s 565 – with digital throttle and shift (DTS), better fuel economy and more grunt – prompted questions. Part 1 answered “How’d you do that?” by reviewing the 565’s torque and power. Part 2 continues to answer: We’ll discuss 565 fuel and DTS.

In this early development engine, one can see the two computer modules stacked behind the second throttle body. Also visible is the digitally controlled shift actuator – mounted on the transom for this test mule.

Fuel Economy. Miserly fuel consumption is a hidden benefit of digital instrumentation. Not just in the boat, but in our laboratory. Since we designed the 525EFI and 600SCi, we have substantially upgraded our dynamometers and engineering analysis tools. In large part, this was done for exhaust emissions, both design feasibility studies and product development, so that we could remain compliant with regulations. As a side benefit: we gained a capability to look at each individual cylinder’s behavior in much finer detail than ever before. Plus, our incredible technicians have the talent to do so.

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565: How’d We Do That – Part 1?

Mercury Racing’s 565 – with digital throttle and shift (DTS), better fuel economy and more grunt – prompted more than a few questions. Mostly variations of: “How’d you do that?” We agreed to blog and provide some answers. In Part 1, I’ll discuss about torque and power. Part 2, fuel and DTS.

Torque. How big are the bombs and where do they push?

The 565’s all new cylinder head flows about as much as is possible with a 2-valve.

As I said in discussing our QC4v 1350, “The Valve Train That Could,” bigger bombs make more power.  We pack more air because we designed the heads and inlet valves to flow better. Admittedly, they’re still two valve heads and not as free flowing as our four valve engines, but they’re better than our previous two valve designs. With more air, more fuel is added for combustion and makes a bigger bomb. Yet, fuel economy is better! How? Improved and more precise fuel delivery to each combustion event makes less wasted (unburned) fuel. Easy to say; hard to do – but we did it. (More about that in Part 2.) Read more

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Virtual Tour – Part 7: Cleaver Revolution

CNC machines produce our perfectly matched 5-blade or 6-blade cleaver propellers.
Skilled craftsmen hand-finish each CNC prop.

Continuing from Virtual Tour –  Part 6: Propellers…we’ll review the evolution of surface piercing propellers, culminating with our amazing CNC Sterndrive Cleavers.

I first reviewed my classic literature collection for information regarding the evolution of surface piercing propellers. Copy from the propeller section of  a 1972 Hi-Performance Mercury/MerCruiser Accessories catalog references our change from bronze to stainless steel that year. I sent Dick Snyder an e-mail to get his input regarding racing propeller history.

Dick Snyder

Three-blade “elephant ear” props on a quad 1250BP rig ready for testing at Lake X.
A 2-blade stainless prop on a merCruiser III drive. This drive was packaged with a 475 h.p. engine.

Dick Snyder was in charge of Mercury’s propeller engineering in the early ’60s.  “When I took over prop engineering in the early ’60s, I had inherited nothing but low rake (6 degree), 2-bladed props. We had no racing or hi-performance props. “There soon came a time when I fell in love with 15 degrees of rake and 3-bladed props for the added smoothness and a little better acceleration. You typically would lose a small amount of top-end going from a 2-blade to 3-blade prop. The higher 15-degree rake allowed the props to “hold” at greater trim angles for enhanced bow lift and greater hull efficiency. This resulted with even greater top-end speeds than the lower rake 2-blade props,” Dick explained. In 1984, Dick was promoted to Director of Mercury Hi-Performance. So he promoted Bob Hetzel to run Mercury’s racing prop and gearcase shop. “We had quite an interesting development of stainless steel props for racing, followed by replacing bronze for stainless steel on our recreational props,” said Dick. Read more

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Virtual Tour – Part 6: Propellers

A technician puts finishing touches on a 5-blade CNC Cleaver sterndrive propeller.
Checking blade thickness on a classic 3-blade outboard cleaver.

Continuing from Virtual Tour Part 5: Sterndrives, Transoms & Accessories…we will visit the Mercury Racing Propeller Department’s finishing area.

People are fascinated with propellers. The response to Scott Reichow’s Prop School blog series proves people are craving to learn more. Our visitors are a bit surprised when they enter Racing’s propeller finishing area. I think they are expecting to see a number of robotic machines pumping out finished propellers. Nope. What they do see is highly skilled craftsmen creating precision tuned works of art. Each puts their finishing touch on every propeller Racing makes – including our CNC machined Sterndrive Cleavers.

Lab Finished props gave Team Mercury a competitive edge in the outboard factory war days of tunnel boat competition.
Have props, will travel. A classic photo of Mercury’s mobile prop lab during the golden era of outboard factory tunnel boat racing.

The trademark, “Lab Finished,” was created by Mercury Racing back in 1970s – when factory outboard racing required a dedicated Engineering Lab to create specialized props. We have proven through the years that hand-working a prop enhances performance. This is particularly true for props run at elevated transom heights (surface piercing) and higher RPMs where impact-induced vibrations and other nuances are amplified.

Only a small percentage of our propeller line is designed specifically for racing. Our most popular propeller is mostly used for recreation: the Bravo I. We first enhanced performance of this MerCruiser sterndrive propeller by lab finishing them for racing. Read more

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Virtual Tour – Part 5: Sterndrives, Transoms & Accessories

Continuing from Virtual Tour – Part 4: Horsepower Highway…we will follow the assembly of Mercury Racing sterndrives, transoms and accessories.

Sterndrives

Mike Riedi inserts the drive shaft on a Bravo One XR Sport Master gearcase.
Mike lowers the Bravo One XR upper housing on the Sport Master gearcase.

Mercury Racing offers a variety of sterndrives fit for virtually any application. Bravo One XRs are enhancements of existing designs while NXT1, NXT6 and M8 drives were designed and developed in-house for Mercury Racing sterndrive packages. The Bravo One XR is a beefed up version of MerCruiser’s Bravo One drive. It was developed to withstand the rigors of offshore racing and performance boating. Our Bravo One XR Sport Master drive targets surface piercing applications. Bravo One XR and Bravo One XR Sport Masters are popular options for boats fitted with 525 EFI, 565 and 600 SCi engine packages. Mike Riedi, who has over 30 years experience building high performance outboard gearcases, also builds Bravo Sport Masters.

Transoms

Joe Backhaus building a M series transom plate.
Dave Vehrs preparing a NXT6 drive for the installation of the dry-sump oil pump.

Joe Backhaus builds Integrated Transom Systems (ITS) for Bravo One XR and Bravo Three XR drives. He also assembles M-Series transoms used with Mercury Racing  NXT1, NXT6 and M8 drives.

Next door to Joe, Dave Vehrs (when not man-handling our 18-wheel Marketing big rig in the Arizona Desert or Florida Keys) builds the drives to go with Joe’s transoms.

When I first started working here, I attended outboard and sterndrive service schools. Drive building was the sterndrive school’s main focus. A beginner quickly learns the challenge of building a drive – over and over – to get the shimming right for correct gear tolerances. It was with this experience that I gained an appreciation for what Mike and Dave do every day. I’m still a rookie; these fellas are top-shelf pros. Read more

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Virtual Tour – Part 4: Horsepower Highway

Continuing from Virtual Tour – Part 3: Outboard Production…we will follow the assembly of Mercury Racing big blocks – those based on GM’s 502 c.i. platform.

Horsepower Highway

Jon VanDenBogart prepares to install a crankshaft in a CNC machined 502 cu.in. cylinder block.
Pre-assembled pistons and connecting rods are matched to a designated cylinder block to ensure proper fit and function.

“Horsepower Highway” is where our 525 EFI, 565, 600 SCi , 662 SCi and 700 SCi sterndrive engine family is built. One technician hand builds each engine from a bare cylinder block to a “long block” (with all the rotating and reciprocating bits fitted inside). Sub-assembly work prior to an engine build includes the rotating assembly: balancing a crankshaft,  matching it with a camshaft, pistons, rings, and connecting rods for later fitment into the block.

Horsepower Highway was conceived, engineered and built in-house. It features a unique rail system and assembly fixtures used to transport cylinder blocks along the line. At each station, all the required tools and components are located for assembly. Each technician controls the speed of his build, moving the block along at their own pace. If something doesn’t look right, it is his discretion to stop right then and there. The build begins with installation of a camshaft. Next is the installation of a crankshaft, timing chain and matched piston and connecting rod sets. The bottom end is sealed with the installation of the oil pan.

The engine is rotated on its assembly fixture to enable work on the top end: The cylinder heads are installed; then push rods and rocker arms. Temporary valve covers mask the valve train prior to paint. An intake is the last component installed before the long bock goes to our paint line. Upon return from paint, it goes back on The Highway for installation of a bell housing.  Color matched valve covers replace the temporaries to complete valve train assembly. Transmissions for NXT1 or NXT6 drive models are installed at this point as well.

Jon rolls a 700 SCi long block along Horsepower Highway.
It’s not everyday one sees a Nanna Yeller 565 rolling along The Highway. Mike Rebedew puts finishing touches on the 8.7 Liter long block.

Long blocks for various engine models look similar. One noticeable difference is the intake (long blocks with naturally aspirated intakes are destined to become 525 EFIs or 565s; those with pressure charged intakes will become 600/662 or 700 SCi’s). Custom color long blocks stand out, too. The “dress line” is where an engine get its true personality. Read more

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Virtual Tour – Part 3: Outboard Production

Continuing from Virtual Tour – Part 2: Quality, Paint, and Quad Cam Production…we will follow the assembly of a Mercury Racing OptiMax 300XS outboard.

2-Cycle Outboards

Gary Aman lowers a 300XS powerhead into position for final engine assembly.
Mike Riedi has over 30 years experience handcrafting high performance gearcases.

Consumer, government and race outboards, featuring Mercury’s low-emissions, direct fuel injected 2-stroke OptiMax powerheads, are assembled at Mercury Racing’s factory in Taycheedah, Wisconsin. Consumer models include the 3.0 Liter OptiMax 250 SportXS and the 3.2 Liter OptiMax 300XS outboards. Watch for a future post on the OptiMax JP, an outboard we build for the government.

The competition outboards produced in Mercury Racing’s factory include our 2.5 Liter OptiMax 200XS SST (Super Stock Tunnel) and 2.5 Liter OptiMax 200XS ROS (Race Offshore). However, Racing’s four strokes — the 60 EFI FormulaRace and the Verado 350 SCi — while designed and validated here, are built off-site at other Mercury facilities in order to share common (and expensive to replicate) production processes.

OptiMax 300XS powerheads await their turn on the dyno.
Mike Hammer inspects each cylinder with a bore scope camera.

OptiMax powerheads are manufactured complete, to Racing’s specifications, at Mercury Marine’s headquarters campus — home to Mercury OptiMax outboard production in Fond du Lac, Wisconsin. Upon their arrival at Mercury Racing, a powerhead’s first stop is one of our 2-cycle dynamometers. Upon completing a power run, they move to Racing’s 2-cycle department. There, technicians inspect the cylinders, to ensure proper wear patterns, prior to final outboard assembly. Meanwhile, another technician is working his magic: handcrafting a gearcase that will efficiently transfer 300 h.p. to the water. Read more

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Virtual Tour – Part 2: QC, Paint & QC4v

Continuing from Virtual Tour – Part 1: Intro.… we will visit Mercury Racing’s Quality Control and Paint Line.  We’ll end up in the 4-Cycle Race Shop where technicians build our exclusive quad-cam, four valve sterndrive engine family. Lets go!

Quality Control

Quality Control plays a critical support role in Racing's manufacturing processes.
The automated Coordinate Measurement Machine is the newest addition to our Quality Control room.

Wherever we can, quality control (the discipline) is built into our production processes. Got to build it in; can’t inspect it in. Quality Control (the department) supports these quality processes (trust but verify) — and measures tolerance’s on everything from machined castings, gears, cylinder bores, pistons, crankshafts and anything else used in the production of Mercury Racing products. QC also plays a critical role in the in-house prototype development of new products. This place was buzzing with activity during the development of the QC4v sterndrive engine platform because so much was new — suppliers, parts and processes. Read more

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Ethanol and Older Outboards

Damage to a boat engine carburetor as a result of ethanol at 10% (E10). Photo courtesy BoatUS.

Mercury Racing has received numerous questions on ethanol fuel in older engines. Here is an article from BoatUS, written with input from Mercury engineers (republished with permission), that covers many of the ethanol issues:

A Shotgun Marriage? Ethanol and Old Outboard Boat Engines

ALEXANDRIA, Va., March 28, 2012 — Ever since E10 gasoline (gas containing 10% ethanol) became widely available several years ago, the nation’s largest recreational boat owners group, BoatUS, has received hundreds of calls and emails complaining about boat engine problems. The majority of complaints concern older outboard motors, those made before about 1990. BoatUS’ Seaworthy magazine asked Mercury Marine’s Ed Alyanak and Frank Kelley, who between them have over 60 years of experience, to find out what’s made these decades-old outboards more susceptible to ethanol’s well-known problems and what owners can do. Read more

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Hi-Performance Boat Operation – Part 3: Prep & Drive

Pre-run inspection of a 700 SCi powered DCB catamaran. Photo credit: Tres Martin's Performance Boat School.
Twin OptiMax 300XS outboards rigged on a 30-foot Spectre catamaran.

In my previous post (Part 2) regarding high performance boat operation, I reviewed basic information on rigging fit and function. Now its time to head to the ramp.

While the boat is still on the trailer, walk around for a visual inspection of the hull.  Next, climb aboard for a visual inspection of the interior and engine compartment (motor well for outboards): ensure everything is in place and secure. Don’t forget the drain plug(s)!  Check your other safety accessories: aboard? In secure locations?

Helm of a DCB M35 catamaran powered by twin 700 SCi sterndrives.
Helm of 50-foot Cigarette Marauder with twin 1350 sterndrives.

Once your boat is launched,  review the helm to familiarize yourself with the location and function of all instruments and controls. Make sure the steering wheel, throttle and shift controls are well within your reach and that you are comfortable with their operation.

If your boat is fitted with K-Plane trim tabs, be comfortable with the location and operation of the tab trim switches. The driver needs to know the location and function of accessory switches such as bilge blower, bilge pump, running lights, horn, courtesy lights and related fuses, or circuit breakers. Read more

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Hi-Performance Boat Operation – Part 2: Rigging Fit & Function

Spring is a great time for newbie and veteran performance boaters alike to get familiar with their craft. For starters, you should review your owners manuals — really, you should — and review the key components of your new boat.

The 300XS is very popular for singe and multiple engine applications.
The 300XS on this Hydrostream features a 20-inch mid section and Sport Master gearcase.

Performance boats vary widely in propulsion and size. Outboards come in 20, 25 and 30-inch drive shaft lengths to accommodate a variety of applications. Mercury (and other brand) outboards are fitted with a standard gearcase for most applications. Hulls that can take advantage of the high power-to-weight ratio of a 300XS may benefit from its wide range of gearcase options. Similarly, Mercury Racing offers a variety of sterndrives for differing power capacities and hull types.

Mercury Racing’s high styled Zero Effort Digital controls.

Mechanical control: High performance outboards are usually rigged with with dual steering cables, a shift cable, throttle cable and fuel line. With performance sterndrives, throttle and shift are accomplished with cables, but steering is hydraulic. These include 600 SCi  and 700 SCi Mercury Racing packages.

Digital control: On Digital Throttle & Shift compatible outboards, such as the 400R and sterndrives including the 520, 540, 565, 860, 11001350 and 1550 mechanical throttle and shift cables are gone — replaced with a single electronic cable. Steering is either electric (Verado) or hydraulic (MerCruiser). Read more

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Hi-Performance Boat Operation – Part 1: Introduction

A Nor-Tech catamaran boat powered by twin 850 SCi sterndrives. Photo credit. Florida Powerboat Club.
The boys from Sunsation enjoy their time on the water. Photo credit: Naplesimage.

With Spring in the air, the timing is right to review the basics of high performance boat operation to ensure you and your passengers have a safe and enjoyable Summer on the water. We include a Guide to Hi-Performance Boat Operation with every engine we ship. We encourage new and current owners to review the book and then get some in-boat driving lessons from your local high performance dealer. Those who do not have a qualified driving instructor in their area may want to consider Tres Martin’s Performance Boat School.

Our operation guide is packed with general performance boating information including a list of descriptive terms relating to propellers, hull types and overall boat performance.  Let’s first review the various performance boat hull configurations.

Read more

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Lovin’ Up Our Classic Big Block

These are some of our people who made the 565 happen.
Color optioned Super Silver valve cover caps Racing's exclusive aluminum 2-valve cylinder head.

New for the 2012 Miami International Boat Show — and enthusiastic performance boaters!

Mercury Racing has updated its core, big block sterndrive! Now, the venerable 525EFI has a digital sibling — 565!

We’ve stroked the block to 8.7 liters (or 533 cubic inches), redesigned the cylinder heads, added a second throttle body to the inlet, broadened the torque curve and increased output to 565 horsepower at 5,000-5400 rpm.

 

Zero Effort digital throttle: the ideal way to control this powerhouse!
Top mounted PCM, TCM and electrical connections makes installation easier.

Mercury Racing’s new 565 runs strong on 89 octane pump gas (RON+MON)/2. It employs dual throttle bodies and electronic fuel injection flowing through a new cylinder head which we designed with improved valve angles for better flow and more precise air and fuel distribution.

Managing operations is a new controller for this engine – the same Propulsion Control Module used on our 1350.

Read more

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RetroJet

The 1959 Glass Craft Aero Dynamic Citation as it looked prior to the restoration.
A custom graphic adorns the top of the replica "alien" engine cowling.

Chris Fairchild is a busy guy. His passion is powerboat racing. He’s been racing tunnel boats for over 20 years.  He not only races his own boats in F1 and SST 120 classes, he also builds and repairs race engines and gearcases. He manages to do this in addition to his “real job” of building custom homes with his father, Jim. So, when he sent me pictures of his latest project, I wasn’t surprised. But it still impresses me that he accomplishes what he does with all of the things going on in his life.

A neurosurgeon approached Chris with the idea of restoring the family boat he grew up with.  The boat started life as a 1959 Glass Craft Aero Dynamic Citation outboard runabout.  The doctor wanted to restore the Glass Craft so he could have something to run on the river during the limited time he is “off-duty.” The challenge was the water levels are too low for traditional outboard propulsion. The doctor asked Chris if the boat could be converted to a jet boat. Chris, always up for a challenge and a journey into the unknown, said, “why not?” Read more

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Prop School – Part 6: Slip

Bob Teague uses Mercury Racing Pro Finish CNC Cleavers exclusively on his 525 EFI powered Skater 388 Super Cat Lite race boat. Photo credit: Paul Kemiel Photographics.

Response to my Prop School series has been been gratifying. It has generated a lot of good discussion (online and off) regarding  propeller design, function and application. One of the most common questions is about prop slip. It is the most misunderstood of all propeller terms.

A wing moving through air produces a pressure differential: low pressure above the wing, with high pressure below it, creates lift.

Propeller blades work like wings on an airplane. Wings carry the weight of the plane by providing lift; marine propeller blades provide thrust as they rotate through water. If an airplane wing were symmetrical (air moves across the top and bottom of the wing equally), the pressure from above and below the wing would be equal, resulting in zero lift.   The curvature of a wing reduces static pressure above the wing — the Bernoulli effect — so that the pressure below the wing is greater. The net of these two forces pushes the wing upward. With a positive angle of attack, even higher pressure below the wing creates still more lift. Read more

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Hello Handsome! Part 3: Details.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

The induction system on the 1973 “Champion Maker” needed no styling. Function (here in Doc Magoon’s US-1 Cigarette) was in your face!

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Communicating the technology within. Some technology is simply beautiful on its face. The induction and air balance system of the QC4v platform required only minor refinement to “style” it. It’s just cool – like the 1970s Kiekhaefer fuel injection trumpets from my dad’s “Champion Maker” Class 1 offshore race engines. With QC4v, some minor shaping and angularity masked the required hoses and clamps, but the inlet runners whisper, “You know why we’re here.” Big air!

Both function and movement are suggested in the exhaust manifold styling.

Cast exhaust manifolds, in a world previously occupied by gleaming polished stainless, was a bigger challenge. We opted to communicate the pulse tuning of the exhaust system through subtle relief in the casting surfaces – indicating the pairing of ports and the side-to-side differences. This also helped function: maintaining a high scrubbing speed of the manifold cooling water. Read more

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“Step right up!”

A favorite of the Mercury Racing stable, our 525 EFI. Its stout components make it a tempting target for upgrades.

There are “tuners” out there that offer supercharger kits for Mercury Racing 525 EFI engines (and others). Some of these kits reportedly boost horsepower and torque as much as 50 percent. They reprogram our engine controller to override its logic and limits. Yes, there is more power to be had – for a time. We program our ECUs to keep engines within their physical limits and offer good power with reasonable reliability and durability.

Ah, the joy of performance on the water! This 525 Bravo One XR powered Nordic is a great running and reliable combination.

One tuner just offered a “price reduction.” Their claim is to make power upgrades more affordable. Beware of the sales pitch, “Step right up! It’s on sale!” Alarm bells should be ringing in your head when you hear those words. If you’re tempted by that offer (and your warranty has expired), please proceed with your eyes wide open because just the opposite is the likely result. Here’s why “affordable” may prove very expensive. Read more

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Hello Handsome! Part 2: Methods.

Inspiration from my “wall”: a great looking engine, necessarily buried in frame rails and fenders, is a Ferrari 4.3L V8.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

One of my favorite details: side cooling ducts on a McLaren. Flowing elegance, if a bit too busy.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Inspiration. There are a multitude of tools in a stylists arsenal. Before any of them can be used, we have to agree to the physical design constraints which define the canvas. Brainstorming basic design alternatives is a prerequisite to an elegant styling execution (not to mention, functionality). It also requires “the eye.” Stylists see things in many places and contexts where most of us don’t. Inspiration can happen at any time. I keep a photo file of appealing details. Inspiration is everywhere: parking lots, race tracks, concourse events, collector displays, air shows, plumbing show rooms – everywhere. My file becomes a wall during a project like QC4v, but settles in a direction, often reinforcing a theme consistent with product history – the DNA. Choosing one design approach sets many things – including the execution journey and styling constraints. Read more

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Hello Handsome! Part 1: How?

1350 on the dyno at Mercury Racing. With the air boxes and covers removed, one can view some of its inner beauty.

Two years ago, I received a call from Skip Braver, owner of Cigarette Racing. He had just received the first 1350 for his AMG Cigarette: “I don’t want your head to explode, but that is one, handsome engine. Just gorgeous!” Thanks, Skip. Flattering. But how did “handsome” happen?

AMG Cigarette: Form follows function. Beautifully. (Photo courtesy of Cigarette Racing)

Function. First, beauty is deep in the soul of Mercury Racing’s QC4v platform, as well as on the surface: it works as intended; it fulfills the needs and desires of its owners better than any engine offered before. In short, it functions as it should (and better than most customers expected). Function defined the structure.

Form. Second, form followed function. I’ve become somewhat infamous for a comment I made back in the 1980s: “Where is it written, that because it is strong, it must be ugly?” This was a discussion with my manufacturing guy at that time, the late Bill Hackbarth. Bill, a stubborn pragmatist, didn’t like the form of the Kiekhaefer sterndrive (now #6) because he couldn’t figure out how to hold the curvacious upper gear housing in a machining fixture. We changed the form, adding a big lug, so he could clamp it tight. When machining was done, we ground that part back off. Propulsion should look good, but… Form follows function. Read more

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Prop School – Part 5: Blade Efficiency

 

 

Turning out.

Rotation. Propellers come in both right and left-hand rotation. Standard rotation for both outboards and sterndrives is right-hand: the prop spins clockwise when in forward gear.  Left-hand props spin counter clockwise.  Left-hand props are typically used with multi-engine applications. The counter-rotation prop works to balance (or reduce) the torque effects from the right-hand prop. Most twin engine applications are setup with the the props “turning in”; the port engine spinning right-hand and the starboard engine spinning counter clockwise. Read more

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Prop School – Part 4: Blade Cup

Illustration of cup added to the trailing edge of a typical thru-hub exhaust prop.
Blade cup location on our Lab Finished Maximus prop.

Cup is a curl formed or cast into the trailing edge of a propeller blade.  When done correctly, The face of a cupped prop blade is completely concave. Cupping is most beneficial on blades which are surfacing, either from transom height (X-dimension) or trim angle. The cup retains water on the blade for a longer period of time, enhancing thrust and efficiency. Racers and performance boaters were the first to realize the benefits of cupping. Now, most recreational props come standard with some cup.

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Prop School – Part 3: Blade Rake

Rake is the relationship of the blade face and the propeller hub.

Rake is the angle of a propeller blade face relative to its hub. If the blade face is perpendicular to the hub, the prop has zero-degree rake. As a blade face slants back toward the rear of the prop, blade rake increases. Rake is either flat (straight) or curved (progressive). Most lower horsepower (“lower” by Mercury Racing’s reckoning) outboard propellers, like Black Max aluminum and Vengeance, have 15-degree rake and are designed to operate fully submerged to push a boat across the water. Typically, higher horsepower outboard and sterndrive propellers have a higher flat or progressive rake.

A good view of our CNC cleaver prop on a NXT1 drive.

A greater rake angle generally improves the ability of the propeller to operate in a ventilating situation. Ventilation occurs when blades break and re-enter the water’s surface — such as occurs with 1) a Bravo sterndrive installed with a high “X” dimension, 2) a surfacing drive (NXT1NXT6 SSM or M8) or 3) an outboard installed or jacked high on a transom. In surfacing operation, higher rake can hold the water better as it’s being thrown into the air — deflecting it aft and creating more thrust. Read more

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Prop School – Part 2: Terminology

Continuing from Prop School….Part 1… Here, I will explain basic propeller terminology and fitment.

Diameter: In “prop speak,” diameter is the distance across a circle made by the blade tips as a propeller rotates.  The proper diameter is determined by the power that is delivered to it and the resulting prop RPM.

A 17 1/2 inch diameter Pro Finish 5-blade CNC prop on an M8 sterndrive.

Type of application is also a factor. How much propeller is in the water (partially surfaced vs fully submerged) plays a role in determining diameter: The more of the prop that is surfacing above the water, the larger the diameter needs to be (so what’s left under water can still push). On rare occasions, diameter may be physically limited by drive type or in close, staggered installations where tips can touch.

Within a specific propeller style, diameter is usually larger on slower boats and smaller on faster boats. Similarly, for engines with a lower maximum engine speed (or with more gear reduction), diameter will tend to be larger. Also, diameter typically decreases as propeller blade surface area increases (for the same engine power and RPM): a four bladed prop replacing a three blade of the same pitch will typically be smaller in diameter.

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Prop School – Part 1: Introduction

I’m Scott Reichow. I manage Mercury Racing’s propeller department (see my previous post, Bravo for Outboards? YES!). Working in performance boating is exciting: It’s fast paced. Propulsion systems and hull designs are in continual evolution. Our customers are generally astute, technically oriented and often quite colorful characters. We’re all performance freaks! We’re all continually learning. That’s what makes my job so much fun!

The prop knowledge guide book. Circa 1980.

If you are like me, your first boating experiences were in lower horsepower boats used primarily for family recreation, fishing, skiing, wake boarding, or general cruising. And like me, your boating experiences and knowledge have evolved through time.

When working with high-end performance boats and experienced customers, one tends to assume people have basic product knowledge. However, a propeller is complicated. Because our backgrounds vary widely, our levels of understanding vary widely, too. So, we’ll revisit the basics and then dive deeper on propeller form, fit and function. Read more

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Oddities & Rarities – Part 3: Race Power

How many outboards can you lay down in a boat?

Maybe this should be “Part 3 through # n” — since few things are odder or rarer than “one-offs” tried in pursuit of a speed record or race victory. Still, some stand tall above others in sheer audacity. Here are some outboards with an identity crisis.

While it ran, it was fast! Count ’em – six sets of exhaust pipes!

Because of the high power to weight ratio of a Merc 2-stroke powerhead, it was inevitable that Mercury Racing’s Fred Hauenstein would lay some outboard engines down on their sides in his Arcadian Unlimted U-86 and go after inboard hydroplane competitors. Read more

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Alpha Male-Ness Without All The Barking

Mercury wants (and is required) to have exhaust and noise emissions compliant propulsion. By being responsible citizens (you and us), our freedom on the water can continue. Global regulations have caused larger marine engine manufacturers to invest millions of dollars in research and development. In that work, Mercury developed an on-board microprocessor that controls all aspects of engine operating performance – including fuel management and exhaust emissions.  The combination of advanced engine components (hardware), fuel calibration development (software) and extensive testing (more hardware and software) led us to a full line of sterndrives that meet U.S. California Air Resources Board (C.A.R.B.) and Environment Protection Agency (EPA) regulations.  But, as we have learned with experience, emissions regulations are ever evolving.

X-haust Noise Reducer logo: noise in, X, quiet out.
Baja 35 Outlaw with twin 662 SCi’s and X-haust.

Just when we thought our job was done, by meeting the CARB and EPA regulations in place at that time, more stringent ones were being implemented by the European Union (EU) Recreational Craft Directive (RCD). We had to do additional work to create “global” engines that would meet stringent EU RCD exhaust emissions and noise regulations.

We tackled exhaust gas emissions first. The EU662 SCi is he highest horsepower we could attain and still meet the EU RCD exhaust emissions regulation. Also, we were able to adjust fuel calibration on the 600 SCi to make it RCD exhaust emissions compliant.

Then, noise.  Engines, as rigged with a typical through transom exhaust system, didn’t pass RCD noise requirements. Aftermarket mufflers didn’t help. Running exhaust through the prop isn’t an option with our engines: too restrictive. Read more

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Bravo for Outboards? YES!

For those of you who may not know me, I manage Mercury Racing’s propeller department. We offer a wide variety of high performance outboard and sterndrive props. I oversee production and manage our prop offerings. My most enjoyable responsibility is helping customers solve their unique propeller issues.

Pro Finish Bravo I XS outboard propeller.
Allison XB-21 BasSport 2 + 2. Photo courtesy of Allison Boats.

I’ve been getting great feedback regarding our Bravo I XS outboard propeller. The latest is from Allison owners who say it is an awesome prop for their XB-21 tournament bass boats. XB-21’s rigged with an OptiMax 250 Pro XS do best running a 27-inch pitch Bravo I XS. Those who power-up to the OptiMax 300XS say their ride is dialed-in using a 29-inch pitch Bravo I XS. XB-21 owners have found odd-pitch Bravo I XS props provide the best hole shot and bow lift. Read more

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Education (and Tuition)

48 MTI and 1350s during testing.

Sometimes education comes unexpectedly. When special designs or capabilities come together in a unique new way, surprises can occur. This just happened: In preparation for the Miami International Boat Show, MTI was testing one of its 48 Race/Pleasure catamarans powered with Mercury Racing’s 1350s and M8 drives.

Dry sump. I’ve written before about the purpose of dry sumping – efficiency. Here we have a 48 MTI with two dry sump M8 sterndrives. Plus two dry sump, quad cam, four valve engines making 1350 hp each. Between engines and drives, dry sump transmissions. Big power; big expectations!

As people sometimes do, the owner tried propellers from another manufacturer. Whang! Blade gone. We warned that these engines produce big fat monster torque (BFMT); we learned this lesson the hard way, too; we designed a special prop series just to handle it. However, this was not the education – just its preamble.
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50 Years of Racing merCruisers – Part 2

Racing MerCruisers: 1988 – 2010 (continuing from 50 Years…Part 1)

1988 Superboat World Cup Champion, Don Johnson, with Sterndrives by Kiekhaefer and engines by Gentry.
The deal that wasn’t: Mr. Seger had big ideas, but did not follow through. Ah, what might have been.

First, a relevant side bar: In 1985, a Swiss businessman and offshore racer, Hugo Seger, approached Kiekhaefer Aeromarine (KAM) to design a racing drive. He had tired of his drive failures. We agreed to a deal: KAM would design a drive, he would pay as we made progress, and would become our European distributor.

KAM looked back at the K-600 sterndrive because it was already tooled! But in the dozen years since 1973, we learned a propeller was happier when positioned higher and farther back. Since we dared not start with any handicap, we began to design anew. “Sterndrives by Kiekhaefer” was conceived. Designers, Larry Lohse and Tom Theisen, didn’t sleep much. Me either. Read more

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50 Years of Racing merCruisers – Part 1

Mercury's founder (my co-founder), Carl Kiekhaefer, came reluctantly to embrace the sterndrive concept. But once on board, he never looked back.

2011 is the 50th anniversary of the merCruiser sterndrive. More important to those of us with the speed-on-the-water gene, it is also the 50th anniversary of racing with merCruiser sterndrives. So, here is the first part of the chronology, 1961 – 1987,  and a pictorial flashback: the evolution of the Mercury Racing and Kiekhaefer sterndrives.

Now in its third printing, Jeff Rodengen's book on Carl Kiekhaefer exposed the previously unknown conspiracy in creation of the modern sterndrive.

For a thorough exploration of the modern sterndrive creation, I recommend Jeff Rodengen’s book, Iron Fist, Chapter 26, The Great Stern Drive Conspiracy, pp. 360 – 379. It is a fascinating work of investigative journalism containing creation, deception, disloyalty, honor and captivating personalities of the sterndrive’s history. Here, I’ll focus on the history of merCruiser and Kiekhaefer racing drives in this two-part series.

merCruiser Racing: 1960 – 1987

Sales literature for the first merCruiser with 327 c.i. and 225 hp.

In March 1961 came the first merCruiser – coined from mer (for Mercury) plus Cruiser (for its target market). The idea was to use more powerful automotive-based engines (like an inboard engine) with vectored thrust, trim and steering (like an outboard) to give better performance than a conventional inboard.

This first 225 hp merCruiser sterndrive proved to work well pushing a boat and was more powerful than competitor’s. But it had an odd worm gear and ring gear mechanism to crank the whole drive out of the water – 180 degrees about the crankshaft axis – for corrosion resistance and “prop changes from inside the boat.”

Don Aronow and mechanic, Knocky House, switched from inboards to race merCruisers in the Bahamas 500 and ever after.

Rapid follow-on design work brought the 110 and 140 hp merCruiser I, introduced in late 1961. It was followed quickly by the 310 hp merCruiser III in 1962. The original drive, renamed merCruiser II, was produced until replaced by a new design in 1970 – without the crank-up mechanism. The II and III were the platforms for racing variants.

Twin 225 hp merCruiser IIs powered the 1962 winner of the 184 mile Miami-Nassau "Ocean Power Boat Race." No bolsters. No canopies. No engine hatch. Just go!

By 1962, there was a “Super Speed Master” (SSM) version of the merCruiser II. From inception, factory owned Mercury Racing teams were conquering all comers in offshore power boat racing. That’s where “the enemy” was. Offshore victories told the world merCruiser had arrived. Market supremacy followed quickly.

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“You Must Have Had Help!”

I’ve had some time to reflect over the Holidays. It was cold and snowy here, so I began dreaming about boating in Florida or Lake Havasu with our new QC4v, 1350 hp engines. Inevitably, that leads me to thinking of the incredibly talented people at Mercury and Mercury Racing who made it happen. Sad how little credit they get for their effort – at least, beyond our hallowed walls. Things I hear make me want to scream, “We have the talent right here!

The QC4v team with their creation just before the Miami Boat Show launch, February 2010.

Whoa! “Quad overhead cams!” And all metric stuff… “Metric equals furrin’, don’t it?” “It looks European.” “Porsche must have designed it for Mercury Racing.” “AMG designed it.” “Lotus…” And so many times, “What block is that based on?” I’ve heard (or read) all of these things, and more.  I’m flattered; that’s good company.  But folks, this was an in-house job.

One thing for sure: Fred K didn’t design it! (OK, I styled it, attended countless meetings about it and did the initial carbon tooling work. And I wrangled the money to pay for it.) No sir, Iclicked nary a mouse anywhere near a ProE CAD station (except once, when I leaned over Tom Immel’s shoulder).

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Dry Sump. Pump it up!

I am pleased to bring you the 4th in a series on the technology of our 1350 engine.

Efficiency. The purpose of dry sumping is efficiency: Put enough oil in the right places to lubricate and cool moving components, but not so much as to produce drag. Then, more power comes out.

The term, “dry sump,” simply refers to scavenging the oil from the lowest point (sump) of an engine – making it “dry.” Except, it’s never really dry. Oil goes almost everywhere and wants to collect wherever there is a low spot. Wherever oil gathers near moving parts, there is not only lubrication, but also risk of drag and even damage.

No tranquility. The oil doesn’t pump gently to the valve train or rod bearings, lubricate and peacefully trickle back down, to make the rounds again. It’s violent in there: Oil goes “weightless” and smashes down when a boat launches and lands. It splashes with every wave impact. It wants to pile on one side, when you round a turn marker. Just think about how your body moves around at speed – and you’re not ducking under a spinning crankshaft! Read more

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Dyno Mighty!

We have an amazing dynamometer laboratory at Racing. The lab is how we know you’re getting the performance and durability you expect. It is independently certified to International Standards Organization (ISO) requirements. Each day, our dynos are put to work: verifying production engine output (video below), validating components, improving quality, reducing emissions or developing power. Although a dyno is helpful for production consistency, it’s indispensable for development. Our engineers and technicians have logged hundreds of thousands of hours conducting dyno testing. They’re pretty good at it.

Moreover, ours is the only lab in the world that can certify exhaust gas emissions on spark-ignited engines over 1,000 hp. Erik Christiansen, our Engineering Director, searched the world to find someone to do emissions testing for us. No one could, so we built our own capability. We are making engines both cleaner and more fuel efficient. We understand dyno processes. Read more

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Sterndrive Losses? Less Than You Think!

Tremendous effort goes into good boat set-up. My conversations about set-up too often turn to power consumed by a drive train,or generated by an engine, and always… propellers. The goal is efficiency – accepting some sacrifice for boat control. Really, your goal is the euphoric joy and adrenalin rush of high performance boating! My goal is to help you get there.

Mercury Racing’s test rig for measuring parasitic losses in drives and transmissions.

Here, I’ll focus on drives. (We’ll cover engine power and props later.) Between engine crankshaft (drive input) and prop shaft (drive output), basic functions are required: gear reduction (so props are efficient); offset of input vs. output shafts (so they’re wet) and ability to change direction (steering and trim are good).

Mercury Racing employs several sterndrives for those functions. Each occupies a unique performance envelope and capacity. Unfortunately, each has parasitic losses: clutch slippage; gear efficiency; number and nature of gear interfaces; U-joint friction; bearing drag; gear oil (quantity, temperature, viscosity and lubricity); and oil windage/pumping losses. So here, drive by drive, are the results of those parasites… Read more

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Go Digital: Drive by Wire!

This is my third in a series about the technology we’ve applied in our new 1350 hp engine.

Computer. It all starts here: The embedded brain of Mercury Racing’s QC4v has ten times the power of our previous PC09 box. That computing power enables far more capability — not just fuel, spark and boost bypass maps — but fine waste gate modulation (learn more:  Big Fat Monster Torque) plus digital throttle, shift and start. Let’s look at DTS.

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Economy of Scale

The more we share (lean on) automotive technology and production volume, the more affordable our products can be. The marine industry is tiny compared to the car and truck world. The high performance market is even smaller. To put it in perspective, GM supplies almost the entire marine industry for a year – performance and mainstream – in one day’s engine production. We cannot (and need not) replicate millions of hours they’ve spent on R&D and manufacturing engineering. We pay for it, a little at a time, in the price we pay for components we buy.

Racing engine refresh cart shows the cam, valve train components, rods and pistons from a 2-valve engine.

General Motors’ big block V8 has served us well – with a relatively low cost platform and many performance parts.  The big block is the backbone of Mercury Racing’s sterndrive products (and most competitors, too). The geometry is simple. The mechanism has endured and evolved for 60 years! Read more

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Big Fat Monster Torque!

This is my second in a series on design features of Mercury Racing’s QC4v engine.

QC4v’s corrected torque is a whopping 1370 lb-ft. Oh, yea!

Torque on our new 1350 is Monster! It rises fast, from 700 rpm idle, and is flat at 1,370 lb-ft from 2,500 to 5,250 rpm and generating 1,350 peak horsepower, before tailing off toward a red line of 6,500. On 91 octane pump gas, not race fuel. Whoa!

(Right to left) Air inlet, compressor, water cooled turbo, and pressure modulation valve.

In other words: Big Fat Monster Torque is more than sufficient to lift the nose of a 48 MTI catamaran, carry it all the way through a hard turn and still plant everybody firmly in their seats for an extended period of acceleration. Just ask my friend, Randy Scism, owner of Marine Technology Inc., about his first test session before the Ft. Lauderdale Boat Show. (Or read, elsewhere on this Blog: MTI Spooled Up!) Read more

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The Valve Train That Could

Cam chain cover hints that quad cams lurk within.

This is the first in a series about design features of Mercury Racing’s 1350 horsepower, quad cam, four valve (QC4v) engine. Throughout the series, I will strive to present unavoidably technical content in non-engineering language.

Bigger Purpose: The only reason to have a high performance marine engine in the first place is to produce thrust from a prop so as to push a boat to: a) go someplace or b) outrun somebody – and come back. Props, drives, transmissions, engine innards and controls all have to do their part, but I skip now to the weakest link in the current high-performance chain: the valve train. (See “Why Rev Limits are…Limits” on this blog.) Read more

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