The Amsoil/Mopar Muscle Engine Challenge - JMS Racing Engines

Using a Milodon pan, windage... 

   

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Using a Milodon pan, windage tray, and external oil pickup, Mike also chose a larger than stock oil filter to get oil out of the crankcase, preventing horsepower robbing windage.

Topping their 440, JMS used the Indy SR aluminum cylinder heads that each builder was required by the rules to utilize. These heads are a great fit to the 440, offering big ports and valves, while rocker gear remains in the stock location. Starting with the CNC ported castings, the ports and chambers of the Indy heads were cleaned up in-house, then the heads were treated to a multi-angle valve job, then assembled with SI stainless steel valves and Isky PN 9375 P105 valvesprings to match the custom roller cam. T & D PN 8215 rocker arms were utilized for their strength and accuracy, and JMS had no valvetrain related issues during their dyno session. To top this combination, JMS used an Indy PN 440-14-12 aluminum single-plane intake manifold with a 4150 style flange, and topped it with a PC Carbs HP 1000 stage III four-barrel.

Instead of utilizing an off... 

   

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Instead of utilizing an off the shelf windage tray, JMS modified a Milodon "top fuel" style tray for better oil control.

Having a dyno in-house was definitely an advantage for JMS Racing Engines. Their engine was ready to go right out of the box, making all its required pulls without any tuning whatsoever. In fact, it was only during the final three pulls of the session that engine builder Mike Johnson made any changes to his engine, stepping up the jets and increasing ignition timing slightly to compensate for the atmospheric differences at Comp. With these changes, their 440 made its best pull of 678.1 horsepower and 563.5 lb/ft of torque for a combined score of 1241.6, finishing fifth overall. We congratulate Mike and the crew of JMS Racing Engines on a strong finish in their inaugural Amsoil/Mopar Muscle Engine Challenge and look forward to seeing them compete in future contests.

The skirts of the Ross pistons...        read full caption The skirts of the Ross pistons were drilled in an effort to keep the piston from rocking in the bore. Mike claims this modification equalizes pressure between the piston and the cylinder wall, and prevents the piston from rocking and scuffing the cylinder.	Did we say JMS used a "seasoned"...        read full caption Did we say JMS used a "seasoned" block? This one has been clearanced at the rear so clutch dust could escape as it was used in a full-race, blown-alcohol application prior to being used in our Engine Challenge.	JMS also fabricated a tunnel...        read full caption JMS also fabricated a tunnel over the camshaft for additional oil control. Since this year's challenge featured a spec engine, incremental power gains were very important.
Indy heads get their oil externally,...        read full caption Indy heads get their oil externally, from the rear of the block. Since the roller valve gear doesn't need much oil, Mike modified his oil supply fittings to accommodate Holley jets, restricting the oil to the top of the motor and keeping it where it's needed most, at the bearings.	Tight combustion chamber quench...        read full caption Tight combustion chamber quench is one key to making power, and JMS Racing Engines got their clearances about as tight as possible without causing damage. Look closely and you can see the part number of the piston has been legibly transferred to the bottom of the cylinder head. JMS sharpened their pencils to figure the proper compression and deck heights so they could achieve the maximum squeeze with their flat-top pistons.	All of this year's competitors...        read full caption All of this year's competitors used the same Indy SR aluminum cylinder heads. JMS Racing Engines chose the CNC ported versions, touching them up and assembling them in-house with stainless valves and Isky roller springs.
		Using ball/ball end push rods,...        read full caption Using ball/ball end push rods, T & D rocker arms are some of the toughest rockers on the market for the big-block Mopar.
The Indy heads were ported...        read full caption The Indy heads were ported and machined in-house for optimum flow. The seats and valves were treated to a multi-angle, race oriented valve job.	Topping their 440, JMS Racing...        read full caption Topping their 440, JMS Racing Engines chose a HP 1000 Holley carb prepped by PC Carburetors and an Indy single-plane aluminum intake. Though smaller than the Dominators run by most competitors, the 4150 series carb performed well and made good power throughout the rpm range.	Incremental gains were the...        read full caption Incremental gains were the key this year since everyone had to run the same basic combination. One of the tricks employed by JMS to free up some power was to under-drive their water pump.
Noticing the turbulent air...        read full caption Noticing the turbulent air in Comp's dyno cell, JMS Racing installed a velocity stack to smooth the air's transition into the carburetor.	Mike Johnson efficiently tuned...        read full caption Mike Johnson efficiently tuned the JMS Racing Engines 440 to more than 678 horsepower on Rockett Brand 93 octane pump fuel. This 440 would be a blast in a street-driven Mopar or would be an awesome street/strip engine.	We congratulate Mike Johnson...        read full caption We congratulate Mike Johnson and JMS Racing Engines on their fifth place finish and look forward to seeing them in future Amsoil/Mopar Muscle Engine Challenges.