can someone explain why. i use 94 chev all the time only because its not much difference from 91 which my car require and it has no ethanol. from my understanding ethanol is no good for the engine unless your tune for it (e85). someone school me

^^ Generally speaking, E10 blends (90% "real gas", 10% ethanol) should be fine for most modern engines. They are pretty much engineered to handle that, so nothing should really break. From an academic stand point, E10 gas has a slightly lower energy content than 100% "real gas", so theoretically you lose a bit of fuel efficiency as a result. The only time you don't really want to have E10 is when you are planning on storing the car -- ethanol is hydroscopic, so it will attract water over time. If you leave the same ethanol in your fuel system for too long, there is the potential for corrosion along the entire fuel system.

Still, enough people claim that even E10 gas makes their engine runs rough, or otherwise give them some other sort of trouble, so I wouldn't really brush those concerns off. From my experience, it seems to me that motorcycles, in particular, seem a little more temperamental against E10 gas.

Beyond E10, however, things could get a little problematic. The US has been trying to push E15 gas for a while, but the industry is adamantly against it (and probably with good reason). My personal biggest concern is, manufacturers are all saying that their older and current non-E85 engines are only capable of handling E10 gas. With an extra 5%'s worth of ethanol, things along the fuel system and possibly the engine itself are going to see some problems because they really weren't designed to handle that.

I would say almost 100% cars out there can handle E15 no problem.

I always wonder why Ford had to put this "FLEX FUEL" badge to show that their car can handle both gasoline and E15 (or E85 or whatever).

http://www.cartype.com/pics/8013/ful...uel_emblem.jpg

What are the differences for Cali 91? Everyone says it's shitty and from imasa sounds like our gas is worse.

Wonder what I should retune my Ecu for?

For my speed3, a Cobb stage 2 OTS 93 octane map will command 19-20 psi of boost and 10 degrees of timing at redline. If I run this map on Chevron 94, I will get knock retard of 4-6 degrees when I data log. A safe tune on 94 would command about 6 degrees of redline. Guys running Cali 91 on the same platform run about 5-6 degrees of timing.

On US 92 from WA, I can run 10 degrees with minimal KR.
With methanol injection and Chevron 94, I am now running ~16 degrees of timing at redline with minimal KR.

Anyone else care to share their tuning experiences on local gas?

before my custom tune i was using my cobb ap, I always used the 91 octane maps with chevron 94. I tried the 93 octane maps but there was just too much knock.

If your car says 91 don't waste your money on 94.

I remember RG did a dyno of US Chevron 92 vs CND 94 on a stock wrx with a stock tune, made something like 5% extra HP, My butt dyno seemed to notice the difference as well in my own car, link: http://www.revscene.net/forums/68154...dien-fuel.html

Correction: CND 94 typo

I think it was US 92 vs CND 94^.
Correct me if i'm wrong though.

So if your car is tuned for 94 will you have any issues running us 92 then?

thanks

^nope...in fact it will be better...us 92 is equal to/better than our 94.

Whats with the fail, daredevil?

if you're tuned for a certain octane gas, i.e Canadian 91, US 92, it's a good idea to use it, especially if you're tuned for 94, running 92... My opinion.

The question was "So if your car is tuned for 94 will you have any issues running us 92 then?"

The short and simple answer is no, which FatalCloud said in his reply. Is his car going to explode into smitherines if he used US 92 octane? No.

Not sure why it warranted a fail. :badpokerface:

Honestly, you should tune your car for whatever gas you use, and more or less stick to it.

My tune I have the ability to load 5 maps on my drive, I have one for my primary shell 91 fuel, and whenever if for whatever reason I am not running this gas (for example I had to fill up in the states), I revert to my stock map, since on that map the car knows how to retard timing appropriately and safe guard itself from knocking or potential harm.

^ That

That's definitely the easy way of course. In my situation, my tuner is US based and they don't have access to CDN Gas. May just go for Cali 91 to be on the safe side.

I was hoping daredevil had some legit points to justify the fail to add to the US vs. CDN gas debate. The research RG did and from other people's experiences have been interesting vs. pressing the fail button.

Some cars don't have an option of switching fuel maps. Just thought I put it out there.

what? your corolla doesnt have a button to change fuel maps? from economy to flintstone mode?

It's called a bicycle, you stupid hipster. :rolleyes:

you have a button that turns your corolla into a bicycle?

You got me there.

Thanked.

FYI

Check out this site Ethanol-free gas stations in the U.S. and Canada

17psi, afr kept the same
chevron 94: 18deg @ peak power
shell 91: 19deg @ peak power
usa chev 92: 20deg @ peak power
chev 94+meth: 20deg+0.5afr leaner @ peak power

gas tank had a couple litres of chev94 left in it on each fill up.
engine is 3.0L v6 twin turbo, 8:1 compression