Hello all--I make it a point to use only the best fuel for my 2002 mainly stock( aftermarket intake & BB bullets ) machine . Mostly Shell premium and a 20 oz bottle of Techron every other fillup, but just recently a new gas station opened up close to me with a 90 octane, no ethenol gas available at about the same price as the prem I now use. Is the octane level too low for our LS1 engines? I like the idea of no Eth but what are your thoughts on this? I have learned a great deal from you guys in this Forum since I bought my Vette in April and just want to say "Thanks" for all of your wisdom about this great car--I am enjoying it immensly!

 

IIRC you are supposed to use 91 octane. All I can find is 87...89...93 octane. I use the the 93.

Wayne

 

I use 93 as well but ethenol, as I understand it, can leave a varnish-like deposit throughout your fuel system as well as shorten the life of any rubber gaskets that it might come in contact with. Wouldnt the 90 oct/no eth be a good trade-off?

 

IIRC, in CA 10% of fuel is diluted with ethanol. You'd probably get a better quality gas with the Non Ethanol 90.

 

Been running 10% 91 for years with no issues at all, 10% /15% will not harm your system at all.

 

The C5 was basically designed to run off 10% ethanol gas....

I don't think you'll really gain anything by running non-ethanol infused gas, especially one that's a lower octane.

The only perceivable gain is you might get like 2% better gas mileage. But I'm not even sure about that. And if I had to guess, the non-ethanol gas is probably usually about 2% more expensive

 

I want E85. The gas in California is trash.

 

I would continue to use at least a 91 octane gas, even if it has 10% ethanol in it.

 

 

Why not compromise and alternate every other tank full but I would also add 20 oz.Techron with every other tank full.

 

Don't confuse ethanol with octane, you still need to run a minimum of 91 octane fuel. Your car will compensate for a lower octane by retarding timing to prevent detonation. But it will only do so after it has detected detonation through your knock sensors. So while running lower octane fuel you induce detonation, which is harmful to your engine. You could run the 100% 90 octane if you added an octane booster to it. Just my opinion and I'm sure there are people here who can explain it more presicely than myself.

 

In my area I can get (for a small premium$) pure gas (no ethanol). I use this in my Victory Hammer and notice better performance. It is also worthwhile because the bike may sit for days or weeks in the South Florida humidity and I don't have to be as concerned with H2O accumulation.
I have also started running my 2001 S430 Mercedes on it - and notice a difference. It has over 200K miles on it and it starts and runs noticeably better on pure gas. I started adding the octane booster and I "feel like" it makes a difference.
I would prefer to use this in my C7 as well (and have been) I just hit 1K miles. The problem/concern is that it is only 90 octane. I can add octane booster to it - but does it really do what it claims? There is some much BS stuff out there! How do you know what is real?

 

While the 10% ethenol gas might be OK for every day drivers, if your car sits for long periods without being started, the 100% gas might in fact, be better for your car. Most small engines suggest 100% gas for their engines because of the longer periods of storage time of the fuel before use.

 

Ethenhol is nothing more than corn alcohol, or moon shine if that gets your attention. Using alcohol, ethenhol or methenhol, has advantages and disadvantages. With pure alcohol as a fuel you can use higher compression ratios. Pure alcohol as a fuel tends to run cooler in the engine. But pure alcohol as a fuel also has disadvatages. An engine needs almost twice as much pure alcohol to cover the same distance or lower fuel mileage. Pure alcohol also attacks seals and rubber like gaskets, etc. To some all this up, if your car is designed to use some amount of alcohol as a fuel there should not be a problem. If you car is older and not designed to use these fuels, you should not use them or use some kind of additive. I'm not an expert, but I have used pure alcohol in race cars. I hope this clears up some things.

The Outlaw

 

Only burn 93 oct with nothing in it, and a can of torco at least ever other fill up... I know over kill but done want to take any chances on the fuel.. Robert

 

What the big deal with 10% ethanol, had it here in Illinois for YEARS, my high compression C3 never had an issue, my C5 and Challenger and bike have no issues with it either. Worry warts.

 

Whats this talk about ethanol gas? In my country we dont have it...Our gas is 91,95 and 98 octane. Shell has techron in it at the pump.

Would I be best to use 95 octane?

 

To the OP and others who use ^^^^ , is Chevron (Techron already added) not available in your area or do you just prefer Shell over Chevron? Unless you have a gauge problem that you're trying to fix, why spend the extra money on bottles of Techron when it's already in the gas?

 

I would try it and see how your car performs. If you get any pinging or it just doesn't feel right go back to your usual gas.