J-SMITH69

i've never heard jeff say that. but if you're going for peak power, more air lower compression. if you're building a street car and peak output doesn't matter all that much, and you want a car without horrible lag. then the other way around.

but you cannot get around this fact, more air makes more power than higher compression.

2000psi

the best would be to have high compression and high boost that would give the most power and least lag. In reality, most of us are running stock internals and THAT is why we are saying to use lower compression and higher boost, it has more room for error during tuning and different types of weather. Higher compression is more efficient and responsive, but not as safe especially for us CA people with our 91 octane pee water.

J-SMITH69

high compression + high boost + race gas + good fuel management = race car

14Bn4G

ENOUGH SAID

JD

High compression+high boost+homadeturbo=blown up ----. High compression+high boost+tons of money in the block and head=you wasted your money. Nuff said there.

beerbongskickass

Just saying "low compression and more boost is better" doesn't explain jack ----. I'm NOT talking about a racecar running 20+ psi with 12.5:1+ compression on race gas. I'm talking about 91 octane pee water in a daily driver with good fuel management and dyno tuning because that is within reason.

What C/R would be too high? 9.5:1? 10:1? 10.5:1?
How much boost is too much? 8 psi? 10 psi? 12 psi?

RENR

im runing a d16a6 block with the z6 head and ill never to back to non vtec. power is smooth allthe way to redline and guess what? thats a 9psi on stock bottom end. i even spike to 11 without detonation. its all about fuel management. compression is about 10.1.oh ya its daily driven too.

stargazer

If you have a d16Y7 (sohc non VTEC) I say save the money that you would spend on a mini me swap and use part of it for just the D16Y8 intake manifold, which flows hella better. If you're boosting, you don't need VTEC. Turbo IS Vtec!

ZexRex

vtec is not impressive at all as far as making big hp numbers go, it's just a hot cam... whooo hoo. turbo is 1000x better than vtec.

the higher compression the more base horse power you will have. so the less boost you will need to get to a certain hp. you will also spool faster with the higher base hp.

however it will be a bitch to tune it for the street, you will need to avoid pinging anyway possible i.e. turn the boost down, run cold plugs, run high octane (107 or 120).

pinging is what will kill the motor.

for a car that will see any time on the street i would say go with the lowest compression possible, you can easily turn the boost up to make that extra lost horsepower. its kinda hard to lower your compression when you find out you can only boost 5 psi without pinging on a hot day and all you can get is ---- 91 octane.

now with a race car its a whole different story... but most ppl still choose low c/r high boost. ie beau's car.

89dxhunchback

My friend swapped Z6 pistons into his D16A6 motor, and I just went on about 100 testing runs with him. he leaned it out a ---- !!! like A/F guage was at 9 o'clock !!! AND he had the base timing maxed out !!!
Greddy kit with SMIC ( 1G DSM ) and FMU and stock injectors !!! 8psi... Its not running right, but running lean is running lean !!! no knock... 8.4/1 compression prob. saved his *** about 99 of the 100 runs...