850HP and Incredible Reliability
If thereʼs one thing Paul Pfaff knows, itʼs how to make big-horsepower engines that last. The only way to achieve this goal is to over-engineer and over-prep everything you do. It starts with the parts used and extends to the combination in which they are used. Then the process is enhanced by the way the parts are assembled, inspected through quality control and finally backed up by testing. Spend some time at Paul Pfaff Racing Engines and youʼll get an idea of whatʼs involved in building a quality marine engine that will deliver plenty of horsepower and last longer than you would expect.
A combination that is starting to take hold is the 850HP EFI using a single 3.3 Whipple supercharger. Built on the same bottom end that produces 1,000 hp in a quad-rotor configuration, the 850 is way overbuilt for the horsepower and therefore does not run on the ragged edge at all. The Pfaff engine starts with a 565ci Dart Bib “M” blueprinted block that has been stress-relieved on Pfaffʼs Meta-Lax machine. This machine vibrates and molecularly restructures the metal on blocks, heads, cranks, rods, valve springs and more. Starting with “seasoned” parts gives you a jump-start on reliability before the engine is even built.
Pfaff uses a Callies 4340 forged crank with Oliver I-beam rods. The pistons are CP forged-aluminum using CP plasma-moly rings. Heads are polished Dart Pro 1 aluminum with severe-duty stainless-steel intake valves and Inconel extreme-duty stainless-steel exhaust valves. The valves are actuated with Scorpion aluminum roller rockers and controlled with Comp Cams high-performance dual springs. A Crane hydraulic-roller camshaft and roller lifters actuate the Manley chromoly pushrods. IMCO PowerFlow Plus exhaust manifolds are included in the package.
Oil control is supplied by a Paul Pfaff 14-quart offshore pan and a Melling high-volume blueprinted oil pump. Spark is provided by an MSD 6M-2 and a billet distributor. Autotronic Fuel Injection Advanced Controls provide the management system.
The key part, of course, is the Whipple supercharger. The 3.3 uses an intercooler, and Pfaff sets it up to run with 5 pounds of boost.
Since this engine is based on a higher-horsepower package (using two Whipplechargers), itʼs much more reliable than most people would expect. Pfaff says the engine should run full throttle in the 5,400- to 5,800-rpm range. The engine can run on 91-octane gas and will put out close to 900 hp all day long. And day after day after that.
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Paul Pfaff Racing Engines
714/894-7573
5362 System Dr., Huntington Beach, CA 92649