The 2008 Amsoil/Mopar Muscle Engine Challenge Winning Engine

To see video of Indy's dyno run click here.

The Amsoil/Mopar Muscle Engine Challenge is one of our favorite events to cover here at Mopar Muscle. We feel fortunate to be able to rub elbows with some of the best engine builders in the country, and we always learn some tricks ourselves in the process. Since all of our previous Challenges have featured stroker motors, this year we decided to change it up a little. Instead of a stroker motor, we decided to feature one of the most common Mopar engines, the 440. To make things even more interesting, we didn't factor the cost of the engines this year. Instead, we required all of the builders to use the same basic parts to build a "spec" engine, and whichever engine made the highest combined peak torque and horsepower would be the victor.

Winning an engine dyno-challenge is sometimes more of an art than a skill. It takes more than just bolting together a good set of parts to make power; it takes a well thought out building plan, many hours of labor, and careful interpretation of the rules. These theories are even more important when building a "spec" engine. Since all contestants were limited to the same basic combination of a maximum .060-inch over-bored 440 with Indy SR heads, the engine builders had to look for incremental gains in order to achieve an advantage. For the second year in a row, Indy Cylinder Head took top honors in our contest, leading a field of stout big-blocks.

So how did Indy capture the win in this year's Challenge? It was a combination of well picked parts, accurate machining techniques, countless hours of labor, and a little unconventional thinking. Starting with a Mopar Performance PN P5007624 Mega-block that was machined in-house, engine builders Russ Flagle and Ken Lazzeri used an Eagle, forged replacement crankshaft with a six-bolt flange, Manley H-beam connecting rods, and Diamond PN 46801 forged, flat-top pistons to form the foundation of their stout short-block.

In order to use a 55mm Comp Cams camshaft to take advantage of improved lobe geometry, the block was machined for oversize bearings and the three center journals were converted to roller cam bearings. Speed Pro piston rings and Clevite rod and main bearings kept the short-block sealed and spinning freely, and a Milodon PN 30930 oil pan was modified in-house for oil control using the new Hemi oil pan as a template. The remainder of the oil system consisted of a Melling M63 standard volume oil pump, Milodon internal pickup, and Milodon PN 32005 windage tray. When it came to the camshaft, Indy consulted Comp engineer Gordon Holloway to help pick their PN CRB-2521R-2525R-R108 solid roller camshaft and Comp roller lifters. By having the cam ground from a 55mm core, aggressive lobes could be utilized, equating to more lift and duration, and improved power.

When building a powerful engine, there is no substitution for cylinder-head flow. Since this year's engine was a spec engine, each builder, Indy included, had to utilize the same Indy SR aluminum cylinder head. There's no doubt that using their own cylinder head in the competition may have given Indy a slight advantage, but since all participants had to use the same head, and since there's no money or prize at stake for winning, we felt our readers would like to see what Indy could do with their product.