Rob94hawk

350-355-383-396 etc. Some people say it doesn't matter with forced induction, some do. I'd like to hear what your expertise thinks.

Discuss.

si

No replacement for displacement.... If you take a stock 350 and put a power adder on it (turbo or blower) say 8 psi and dyno it, and take the same car every thing else the same but a bigger displacement it will make more power! You have a bigger area (more cc) that means more air for better conbustion and a longer stroke makes more tq. No if ands buts about it!

They might be saying that because if you have a set hp you want and just aren't there all you have to do is up the boost... much easier than taking all apart and building big...

MikeGyver

Cubes dont necissarily matter, FLOW matters.
If flow increases the same percent as cubes, then yes. If you have a bigger motor that flows less or the same, then no.

jsetzer

In the end its how much air you can get into the cylinders. Boost is increasing displacement. Normal 1b or 14.7ish psi is atmospheric. 14.7psi of boost on top of that more or less doubles the volume of air. So that 350 more or less becaomes a 700cu inch. The 427 more of a 852. Of course flow and friction and a ton of other stuff goes into it.

Guess the answer is all of the above.

Remember the whole thing is a system. More cubes will need a bigger blower to push more air. Thats why we end up with wierd stuff like my 70 only being good for 600 hp on a 350 - but can make 700 on a honda. Plan everything to be part of a package.

reamo04

if it mattered too much, do you think there would bes o many insanely quick 4 and 6 bangers? Look at a grand national, 3.8L thats faster than most of our v8s once modded. I haev a SMALL v8, 294 cubes, and plan to go low 10s high 9s with it

97FormulaWS-6

It matters in the sense of what are your goals and limits.... It's all about pumping air and moving air. The more air you can pump the more power you can make.

A lot of the high-boost "small" motors are being pushed to their limits; while similar HP can be made from NA "large" motors.

You won't ever see a 4-cylinder Top-Fuel car; the motors just can't "pump" that much air to generate the HP for a car like that.

jsetzer

Look at the tq curve of a 1000hp v8 and a 1000hp honda. They both make 1000hp right?

dangalla

awsome article from gm high tech on this subject

http://www.gmhightechperformance.com...est/index.html

cusz28

displacement shouldn't matter so much as the flow, like mikegyver said. but everything has to work together like jsetzer. the most important thing to remember is not to just "add more boost". the turbo (or supercharger) must be carefully matched to engine size and hp requirment. boost pressure (psi) is just the number telling you what pressure will be at the required hp level. turbonetics has some amazing articles on how to choose a turbo for your application. http://www.turboneticsinc.com/choose_turbocharger