It's not that tough to get 1 horsepower per cube these days. It is much more difficult to get 2 HP per intake cfm; you need a really good cam and intake combination to get there.
x2. The hp per cube goal is fairly easy. The hp per cfm is not. In addition to what Jay said, any engine that gets 2 hp per cfm is likely to be a high compression deal. Possible on high octane pump gas? Yeah, possible, but not at all easy in my opinion. Getting 2 hp per cfm requires everything to be optimized and sacrifices to be made, such as driveability. We are of course talking about naturally aspirated engines.
JMO,
paulie
Okay, that makes more sense, I could not understand the numbers I was coming up with. 1 hp per cube is not hard but 2hp per cfm is a work of art.... I go to a lot of chassis dynos on dyno days here and it always seems the gassers are on the low side and the diesels are high. I have never seen an engine dyno so I am not sure what goes on there. I have asked the operator what the loss differential is, but he says there are a lot of variables, so it's hard to compute. Using 20%, my 243hp would only be about 292hp at the flywheel then, kinda sick, huh? This next spring I will put my pickup on the dyno again and get a comparison with the new top end. The old combo had stock D2 heads, performer intake, 280h comp cam, and 750 edelbrock carb. I don't have the exact compression ratio, just guessing about 10.5.
Nick
I read thru thread and did not see anyone mention this:
When you say 243 to 292 hp you are adding to the small number. A 20% loss would be actually 305hp - 20% loss to get the 243
Your current would be 294.8 or a 368 hp - 20% would give you the 294. With a c-6 trans you will lose an additional 25hp from my testing years back.
That would bring you up to 393HP but I think you are really making a honest 400 flywheel HP. Large tires eating it up for one.
