candymanjl

last time out on the dyno I ran 509whp on 39 pound injectors so you'll be fine on 39's for mid 400whp range.

with E85 stoich is around 9.5:1, you end up running around 8:1 to be a little on the rich side. that's a LOT more fuel just to match the same power as gasoline, about 50% more fuel.

track only or weekend only car and E85 is cool. daily driver or a car you plan on taking on trips and E85 is gay.

BruceH

I tested the local supply of e85 prior to tuning. It was 79% ethanol. This computes to 9.9 stoich. E10 is 14.1. The stoich isn't a direct comparison for fuel consumption, it's just a number that represents lambda. The numbers that are measured post combustion with a wideband or sniffer are the same for e85 or gas. For example when I was tuned today the sniffer indicated high 11's af during the wot pull.



I ran a half tank on the e85 base tune and mileage was 13.85. For similar driving conditions I usually average around 16 on 92. Today I drove to the tuners on the base tune, did a bunch of pulls while he was tuning for different pulleys, drove back, and got a hair under 14. Keep in mind I have 4.10's. I really think that with all highway driving I could be around 18mpg on e85. That's not too shabby for the hp I'm putting down with it.

candymanjl

I'd have to agree, on E85 with those MPG's that's not too bad.

There's E85 down here in a couple places so a lot of guys run it. Go north of here though and you're back to 93 octane. I go to North Carolina once a year and I like just keeping my 93 octane tune since I can get that everywhere I go. At some point I'll just build the motor and then I can up the power and still run 93.

Riptide

I'm not sure why but after installing my KB the fuel mileage has been terrible. As in 14mpg terrible. Seems like some of you are doing better than that so I don't know what the issue is.

JDWalton

as pointed out earlier, I'm on stock pump with a BAP @ 80% and 39# injectors, running 9.5psi boost. Making 536 rwhp right now. I think some people bite on the logic if its bigger it has to be better, instead of saving money to spend on other things, and upgrading as required. Although I am max on the entire system and am at much higher crank HP then is generaly considered all right (or even smart) to run on the stock bottom end.

For your requirements, 39 should be fine for any kind of pump gas. If your going to go e85, then the GT500 pumps and the 60s should do the job for you, though as others have pointed out, check with your tuner first and consider there input, vs what kind of gas you want to run, then decide on what to buy and from were. I'm a big fan of spending money once for something thats gonna get me a good amount of use.

candymanjl

Well you can't add 150-200 hp and not expect your mileage to suffer ha ha. That said I noticed that my milage was getting bad with the Kenne Bell tune as well. More so lately for some reason even though I drive the same pretty much all the time.

Overall I was unhappy with their tune and they refused to do anything for me to fix it. I just went to a Brenspeed tune and so far much better! Too soon to tell if my mileage has really changed but if the little meter on the dash is to be believed it's better. I'll know for sure after a tank of gas.

Lately I was getting about 16 mpg with around 30% highway 70% city driving. Stock I was getting more like 18-19mpg with mixed driving like that.

Riptide

Yah I suppose the tune being the issue makes sense considering the car seems to run fine otherwise. I knew it would drop (the mileage) but just didn't expect it to go from 17-18 all the way down to 14. And that is with staying out of boost for the most part. If I am aggressive it can be as bad as 12-13..

Fuel

Did this really turn into a mileage discussion on FI cars? Guess that part of it doesn't really mean anything to me since my car isn't a DD.

candymanjl

yeah when the car is your DD and you see how often you're filling it up then you'll care otherwise you're right, who cares about MPG's when you've got a lot of power.