what is better? e85
 

what would make more power
e85 @10:1ish comp and 10psi
or
e85 @8.2:1 comp and 20psi

i cant seem to find anything on the interweb that compares these to scenarios.
low comp high boost or high comp low boost?
does 1 have an advantage as far as more low mid or high end power?

Re: what is better? e85
 

The type of fuel is irrelevant for your question. What turbo are you using, where is it most efficient?

Re: what is better? e85
 

TD04L on a 1.5, idk where it is efficient.

Re: what is better? e85
 

If raising compression was more efficient than turbos, don't you think we'd all run high compression? If you are talking about peak power or average power, higher boost is going to win when you are talking about a 10psi difference. Same example, 10psi vs 11-12psi, it's hard to say. Depends on a lot of variables. Low end will almost definitely go to the higher compression setup. Midrange I'd say is a toss up, and top end I'd be more willing to say the turbo.

If you want an all inclusive answer to your question, run the highest compression possible that keeps you from being octane limited. Meaning if I can make 400whp at 18psi on 93 pump with 9:1 compression and I have plenty of room for error, and I'm looking to only make 400whp, it is more efficient to run higher compression and lower boost as you will make more power everywhere with the increase of compression and lower boost = less work needing to be done on the air = lower IATs.

Re: what is better? e85
 

10:1 and 20psi. Buy real pistons and do a real tune.

Re: what is better? e85
 

ok from doing some more research and reading your repilies i have figured that the higher comp is just going to give a little more lowend power but more boost is always going to overtake that gain.
if its lagging i will just downshift

Re: what is better? e85
 

That's what we like to hear ;)

More boost > all

Re: what is better? e85
 

jago like you said b4 the fuel is irrelevant?, just my experience when i burn gasoline it seems to burn a lot quicker then if i burn some ethanol. i assume it has a different burn rate and i know it doesnt have the same btus as gas but is it not to big of a deal?

Re: what is better? e85
 

I think what he meant is that it didn't matter what fuel for the comparison: low comp and 20 psi will make more power on 93 octane, e85 or race gas.

Re: what is better? e85
 

Bingo