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DYNO TEST ENGINES454 CHEVY BASE ENGINE The 454 Big Block Chevy engine is the most common in service today. Found in numerous Jet and Bravo drive boats. Their is basically two versions, the 330HP version with 2 bolt mains, cast crank, 3/8" bolt forged connecting rods, oval port heads, dual plane intake manifold and 650 Holley carburetor and the 365 to 425 higher horsepower version with 4 bolt mains, steel crank, 7/16" bolt forged connecting rods, rectangular port heads, dual plane intake manifold and 750 Holley carburetor. The maximum displacement for the 454 Chevy base engine is around 500 cu. inches without too much trouble because the blocks are of a completely wet cylinder design.
712 HP 467 CU IN CHEVY For this Dyno Test Engine we wanted to go to the Max, keep in mind that the engine had to run on pump gas. Starting with a stock 330 HP boat engine, bored it to 467 cubic inches (.060 over), beefed up the bottom end with 4-bolt mains, stock forged steel crank and .25 long connecting rods. Increased the compression ratio to 10.5 to 1. Added a set of AFR 315 CNC cylinder heads, single plane CNC Super Victor manifold with a 1250 Carburetor. A Lunati solid roller cam was used with a duration of 265/275@.05 and .750 lift with 1.7 roller rockers. Then, of course, a set of Lightning 2" headers. Next, to our in house Dyno where it cranked out an amazing 712 HP @ 6800 RPM, with 578 FT LBS of Torque @ 5700 RPM. Interesting side note: we tried 1.8 rockers that brought the net lift to just under .800 and saw no increase in Torque or Horsepower. After talking to AFR, it was suggested that the cylinder heads were at their upper limit and to try their bigger 335 or 357 cylinder heads. Now, as stated through out this website, lets not get to excited about that horsepower figure. The Torque of 578 FT LBS @ 5700 RPM is what matters. This engine combination is pretty limited to a very high RPM band. This engine would work in a Jet boat with C to D cut impeller or a V-Drive Flat bottom or any application that would let the engine spin up to 7000 RPM. Actually, this engine would be great to put in your '68 Camero. This engine and cam combination would be considered high maintenance. next phase: cam change to a lower maintenance combination.
502 CHEVY BASE ENGINE The 502 Chevy base engine is the same as the 454 Chevy base engine with 4 bolt mains, steel crank, 7/16" bolt forged connecting rods, rectangular port heads, dual plane intake manifold and 750 Holley carburetor. The only difference is the engine block, which is Siamese in design. It can be bored to a maximum of 4.625 which will yield 537 cu. in. with a stock 4" crank. All the aftermarket blocks copied the Siamese design and added clearance for stroker cranks.
802 HP 632 CU IN CHEVY For this Dyno Test Engine we wanted to go to the Max, keeping in mind that the engine had to run on pump gas and use a conventional 24 deg cylinder head. We used an aftermarket tall deck cylinder block, 4 3/4" stroker crank and long connecting rods. Forged pistons with a compression ratio to 10.5 to 1. Added a set of AFR 357 CNC cylinder heads, single plane CNC Super Victor manifold with a 1250 Carburetor. A Lunati solid roller cam was used with a duration of 278/280@.05 and .750 lift with 1.7 roller rockers. Next a set of Lightning 2" headers. Next to our in house Dyno where it cranked out 802 HP @ 5800 RPM, with 773 FT LBS of Torque @ 5300 RPM. It actually made 797 FT LBS of Torque @ 4400 RPM, but is considered unusable Torque. The Torque numbers hold pretty good until about 5600 RPM and then start to fall off. This is the upper limit to the conventional 24 deg cylinder head. This engine and cam combination would be considered medium to high maintenance. next phase: cam change to a lower maintenance combination.
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