When the 2004 Jeg’s Engine Masters Rules were announced, the wheels at MPG began to turn. The Engine Masters Challenge was billed as the “ultimate engine builder shootout.”  And it is!  Builders from across the country brought their best 410 c.i. American small block engines to “dyno race.”  This challenge eliminated variables such as track conditions, driver ability and pitted engine against engine by the numbers.

The engines were divided into 3 groups for the first round of “dyno racing.”  The top 2 engines from each qualifying dyno went on to the final competition.  MPG Heads won their dyno in the qualifying round.

We knew there would be a few stroked 351 Clevelands and Windsors in attendance.  But we wanted to show that there are more than just these two options. In an effort to do something a little special for our loyal Boss 302 customer base, the rules for the competition were carefully scrutinized without a concrete answer.  The rules committee was contacted with our proposal to enter a Boss 302 ,and the concept got a green light.

The Rules allowed up to 410 cubic inches, run on spec 92 octane fuel through 3″ exhaust with mufflers. You can read the rules in their entirety at www.enginemasters.com.

How do you squeeze that much displacement into a 8.2 inch deck block?   The details on how we did it are below.

Block: The cast iron Dart block started life as a standard Boss 302 block with an 8.2″ deck, 4″ bore and 2.249″ main journal size.  It had steel four-bolt main caps, a priority main oiling system and Siamese cylinders.  While the main journal size went untouched, the block was treated to a .250 over-bore, bringing the bore size to 4.250, leaving a scant .130″ between cylinders.

Crank: [Pic 2] 
The steel crankshaft was a Scat forging that was custom ground.  While the main journals are standard Boss 302, the rod journals measure a small 1.848. Stroke was 3.6″.  That’s .600″ longer than stock.  These crankshafts are available from MPG in various strokes, balanced and ready.

Connecting Rods:
The connecting rods, available from MPG, are part of the secret to a large displacement Boss 302.  Measuring only 1.84″ at the big end and 5.470″ center to center, the rod ratio is 1.51.  The Boss 302 block requires only 1/16″ ground from the block for rod clearance, a lot less clearancing than a standard 347 stroker.

Pistons:
The custom forged pistons from CP were lightweight, flat-topped .043 gas ported pieces with very high ring placement.  The pins for this unique assembly were .890″ in diameter.  MPG prepped the pistons and coated them with Techline engine coatings.  A thermal barrier coating was used to coat the top of the piston, and an anti-friction coating was applied to the skirts.

Camshaft: [Pic 3]
 A solid roller camshaft was custom designed and ground by Cam Research, another Scott Main company.  Duration at .050 is 250 intake and 252 exhaust with .744/.725 lift respectively.  Lobe separation was 106°.  The seat-to-seat duration was short and the lifter acceleration was fast.  When a valve was open, it spent a lot of time near full lift.

Cylinder Heads And CNC Porting: [Pic 4]
The bare 3V cylinder heads came from CHI of Australia.  These quality castings came machined for 2.15″ intake valves and 1.65″ exhaust valves.  MPG’s finished heads used Cam Research’s stainless steel valves of these dimensions.  The canted valve heads featured stock Boss or Cleveland valve angles, but the ports were downsized to 218 cc on the intake, and the exhaust port was raised .400″.  The chambers included a revised spark plug location and a modern, heart-shaped “quench” combustion chamber.

The guys at MPG agree that one thing you can learn from building Super Stock motors or in any form of racing where rules restrict porting, is that there is more flow and power to be had in a simple valve job than one might think.  The porting work here concentrated on the short turn radius, the bowl and, of course, the valve job.  To keep port velocity high, the finished intake runners were not opened up at all. Scott hand-ported one short-turn radius and intake bowl shape that he found worked efficiently.  Flow numbers were in the 343 cfm range at .650 lift and the low lift flow was “strong.”  Then the entire port shape was then digitized and refined on Master Cam software, and the final shape was applied to all of the ports on MPG’s simultaneous 5-axis CNC milling machine.  The chambers were then coated with Techline’s thermal barrier coating.

The finished chambers measured 64.5 cc’s.  Scott opened them up a bit to take advantage of the big bore.  Compression ratio for the engine was 12:5.

Intake Manifold:
The intake manifold was a Ford Racing #M-9424-B302 that was both filled and ported on the inside only, per Engine Master Rules.  The flow in the intake’s worst runner was improved by 33 cfm and the air/fuel distribution was modified until it was extremely even between runners.

Roller Lifters: 
With valve spring pressure at 240 lbs closed, strong and reliable valve train parts are a necessity.   The roller lifters are from Cam Research.  The reliable, lightweight design features the largest axles in the industry. 

Windage Tray: 
An MPG 302 windage tray was used for this small block project.

Stud Girdle: 
The stud girdle used was by Jomar and is a requirement with fast cam ramps and high spring pressures.  Without a stud girdle the high spring pressures actually bend the 7/16″ rocker studs.  By tying all 16 studs together the bending or “deflection” of the studs is minimized.

Reverse Cooled Engine: [Pic5] 
The water pump pushes coolant into the block then into the cylinder heads in a typical V8 cooling system.  With most of the engine’s heat generated in the combustion chamber, cooling the heads first can help curb detonation and increase horsepower.  MPG’s reverse cooling kit is designed to do just that.  Cold water flows from the pump to the front and back of the heads then down through the block and out a freeze plug on each side to the radiator to be cooled again. 

MPG will have these reverse cooling kits available in Dec. ’04 for small and big block Fords. More information on the Jeg’s Engine Master Contest can be found at www.enginemasters.com.  Cam Research products can be found at www.camresearchcorp.com.  Below is a list of the competitors, their scores and how they placed in the 2004 Engine Masters Challenge.