ProEFI

I'll go 10:1 from what I read from the guys up here.

walhan_qtr

I wouldn't do 10:1

I would probably stick around 9.5 if it was me!

ProEFI

I was thinking of 9.5 cause it's seams much safer with the more boost + nitrous I'm going to run but the guys here keep saying it will be too much for maxing out the D1.

btw I still looking for the prices you didn't send buddy :yes nod:



best,
Mubarak.

Chance42

In the end it's all about cylinder pressure and usable power made. Whether you make 1000 hp by nitrous plus 18 lbs of boost on 9.5:1 scr or 10.1:1 and 15 lbs of boost and nitrous.Those numbers are just for arguments sake. The 10:1 scr car will have better street manners and most likely better fuel mileage if that matters. Compression adds heat and pressure, but so does boost, nitrous cools the temps but adds pressure. It's all a game of what you want out of the car. Do you want a race car that can be "driven on the street" or do you want a street car that can be raced? Lower cr and higher boost will maybe net you a little more hp in the end but the d1 isn't the head unit to shoot for with low static compression ratio. You'll max the head unit before the motor gives, with a proper tune anyways.

I used to think that way when I was going for a ysi build. I wanted 9.5:1. I opened my eyes to modern projects, fuel, and tuning capabilities and I would go 9.8:1 at the lowest unless I was running a large turbo setup or a f3, crazy race car stuff. 10:1 is perfect for 95% of blown street cars imo.

David Bruns

10.5:1. Going F1X on a lsx 427 from Modern Airflow Dynamics, BR7 Brodix heads