Really good data today.
In the past, I've always correlated duration splits with intake/exhaust flow ratios. Today's data proved that more of a duration split in conjunction with an exhaust port that isn't up to snuff in comparison to the intake port is necessary if you're looking at making horsepower and torque.
I kept everything the exact same as the last engine, including the timing, carb spacer, you name it.
As a recap, both engines that we have examined have been relatively common 445 cubic inch engines. Trick Flow heads. Performer RPM with the divider cut down. Same rods. Same pistons. Same crankshaft. Same distributor. Same timing. Same carburetor. One engine had a 231/239 @ .050" hydraulic roller on a 114. This engine had a 231/235 @ .050" on a 113. Both cams had .630" lift. Both cams were on a 105 ICL.
The previous engine made 547 hp @5750.
If we compare apples to apples (the previous engine used a 2" Super Sucker") the engine today made 527 hp.
However, it would be unfair if I didn't try to tune for optimal setup, just in case this camshaft "liked" something else. We did a few tweaks here and there but the engine really responded when we changed from a 2" HVH Super Sucker to a 1" HVH Street Sweeper. We gained 9 hp there.
So at the end of the day, where were we? We ended up with 536 hp @ 5500 with 575 lb-ft of torque at 4500.
What was the difference between the two engines? 11 hp and 13 lb-ft of torque.
So who won?
