Author Topic: APR/Unitronic on Chevron 94?  (Read 1376 times)

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jesse

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Re: APR/Unitronic on Chevron 94?
« Reply #20 on: Apr 17, 18, 10:26 »
Side questions: Who sells the best gas in the US? Can i use E85 in a car not specifically tuned for it (but tuned for 100 octane)?

Qogu

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Re: APR/Unitronic on Chevron 94?
« Reply #21 on: Apr 17, 18, 11:08 »
Side questions: Who sells the best gas in the US? Can i use E85 in a car not specifically tuned for it (but tuned for 100 octane)?

Ethanol has 76,000 BTU's per gallon
E85 has 83,000
Gasoline has 114,000

Too answer your question I wouldn't. I'm no rocket scientist but If you have more time this is what I've learned from e85

from the little experience I know. If not upgraded as I don't know what you've done to the car, your gonna need larger pump and injectors. E85 is closest to 105 octane as well as Stoich for E85 is about 9.7 as opposed to 14.5 for regular gas. Gas has more energy per unit but because of the lower stoich number, you can and need to run more E85 to get to that stoichiometric level. This means that the amount of energy per charge is basically equal. However you typically get cooler intake temps.

Important thing to remember it doesn't matter how much energy a certain fuel contains - you can't burn just fuel, it has to be "diluted" with air. Think about nitromethane, it has what - 32,000 BTU's per gallon, so who would use that ****, right? Wrong - it only needs 2 parts of air to burn, making 32,000/2 = 16,000 BTU's in the mixture.
« Last Edit: Apr 17, 18, 11:16 by Qogu »
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jesse

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Re: APR/Unitronic on Chevron 94?
« Reply #22 on: Apr 17, 18, 12:18 »
Hmm

So if my car likes to run A/Fs closer to 10 than 14 it probably not the worst idea to put e85 in it? I mean I probably won't but if it doesn't hurt I guess I could try and see what happens
Our gas up here is no good for it as is anyways

83RedRoc

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Re: APR/Unitronic on Chevron 94?
« Reply #23 on: Apr 17, 18, 14:57 »
You need ~25% more ethanol than pump gas, so no you can't run it, you'd max out the adaption channel and it'd throw a CEL and before then you could do some serious engine damage.    Timing wise sure you'd probably be fine, its the lean condition that will cause engine damage.   Flex fuel tunes are usually combined with an ethanol sensor so that it knows how the mix is to compensate the amount of fuel being delivered, whatever that may be.

I usually use Chevron or Shell south of the border, but thats just sheer " I've never heard of that place before not going there " talking.   They could be fine.   You could run 94 from up here with a booster in it, ( like Torco, not the shit that canadian tire sells ) but I wouldn't recommend it for much more than a track day or similar,  as it leaves some deposits.   But you should be able to make up 100+ octane.   Or just buy race gas ..