kill4thril

Well like it says looking for a recommendation on what compression ratio to run on my 408ci. when I first started the build I planed on getting down to the low 9s or even high 8s but that was when I was planning on just running 93. then I found a few gas stations with e85 so am planning on going that route. But still want to be able to fill up on 93 for trips out of town every now and then. But with e85 I have been seeing alot of different compression ratios and just wanted to get some input on what you guys think. as for boost level I'm not 100% set on a pressure but figured I would start around 15psi or so and work from there.

Thanks for any help
Jesse

JoeNova

Leave yourself a margin for error for when you are running pump gas.

That being said, I would go at least 9.6:1 so you aren't giving up any power on E85 and are still able to run some boost on 93.

Anything over probably 10.4:1 and you will need to have a good intercooler and water/meth injection to keep pump gas happy.

Yes, you can get away with more. These numbers leave you some safety margins. Its going to depend a lot on your setup, cam size, exhaust backpressure, etc.

kill4thril

I planed on water/meth for the engine and the turbo is a s480 with the T6 1.32 ar. The car won't see much 93 just a few times a year for the trips out of town to the car shows don't plan on really getting on it with 93 just want to make sure it will still be drivable on it in case I get stuck out without e85

Forcefed86

iTrader: (4)

Pretty relevant post about 10 down from yours...

https://ls1tech.com/forums/forced-in...ssion-e85.html