I have a e85 tester, but my question is has anyone here had a problem with the quality of e85 fuel? I am worried that if I get a tune on Amoco e85 then I purchase sunoco, mobile, or shell e85 even though its still 85% ethanol maybe the quality won't be as good and damage to my engine can occur. Just wondering if that's a possibility.

 

i know they make seasonal blends of E85 which would most likely require a retune. as far as quality of E85 between brands i would imagine is the same as the quality of 93 between those brands. Probably wont notice a difference even though some people swear by only a certain brand of 93/e85. just my 2 cents.

 

The only issues I have heard of are additives that some stations will put in the E85, which is truly only meant for the 87-93 octane fuels. This is likely the culprit of clogged injection (gunk). Otherwise, I have not heard any cases of bad E85.

 

If you're tuned to the bleeding edge of E-85s limits, then you better be testing the spec gravity with each fill-up. Especially in the winter when they drop it to E70 in northern states.

If you have a decent safety buffer, then the LTFTs will easily make up the difference between E70 and E85. Just cruise for a while after a fill to get things settled and keep an eye on the wideband to make sure you're still in the same A/F range you tuned for.

 

Just double checked some numbers and assuming ethanol as 34% less energy than gasoline then there will be ~ -7% change in fuel consumption going from E85 to E70.

LTFT's will make up for this, but a change in the global injector scaling is warranted. I like to keep my LTFT's <5%, or closer to 3% if I can.

 

Weird to hear an FP Black referred to as "responsive" haha. By that I mean how different "streetable" is considered from one person to the next. A friend of mine had about 500-550whp and it was fun when he would wind it out to "you're getting a ticket" RPM. around town, otherwise, it was a turd. My car was always opposite, so I definitely noticed the difference. My 430whp was faster everywhere but the drag strip.
he later downsized lol
he had stopped drag racing at that point, though.
aaaanyway, FP makes good stuff. I've only ever had one of their turbos fail on me. That's not too bad for an aftermarket company.

 

Lol yeah It’s all subjective I suppose. I just don’t see it being any less responsive than when I had a full bolt on stock turbo set up. But, then again, I’m cool with the car feeling like a Camry just getting around town.

 

Weird that the thread sends to have changed. FWIW an FP Black would need e85, a high CR, and a 2.4 to get anywhere near stock spool characteristics. Especially if I remeber you having an aftermarket IM and other peak-power producing items that slide the graph to the right. I may be exaggerating a bit, but anything above a red is usually a bit delayed when it comes to spool. I did a quick search and can't find a dyno sheet, but someone here will have one.

 

Lol maybe I just forget what a stock turbo felt like and got used to the lag.