GMJim

Hello all
New Z owner with yet another question. I've seen all the threads and opinions about ethanol vs. non ethanol fuel and up to now I've been using nothing but non ethanol Shell 91 for my GS. Now that I have the ZR1 I need to up the octane (I think?) to 93, according to the manual.

Excerpt from the manual.
If the vehicle has the 6.2L V8 engine
(VIN Code T) or the 7.0L V8 engine
(VIN Code E), use premium
unleaded gasoline with a posted
octane rating of 91 or higher. For
best performance, use premium
unleaded gasoline with a posted
octane rating of 93.

The ONLY Top Tier NON ethanol fuel in my area with octane levels high enough is Shell 91. The higher 94 octane is a Sunoco 10% ethanol blend. I know my Z was built for the use of ethanol so I was thinking for storage over the winter (yes I'm dealing with that where I am now) that I'll fill it with the Shell 91 (no ethanol to separate over the 5 months) and use the Sunoco through the summer for the better (higher octane) performance. Like most of you I'm admittedly a little **** about this subject and wanted to get some other opinions. Am I concerned about nothing here?
Thanks

BearZ06

Probably concerned about nothing but your plan sounds good. Too bad about the winter storage.

Gary '09 C6

I normally alternate between Shell V-Power 93 and Chevron (w/Techron) 93 (both contain 10% ethanol).
But, any top-tier 93 should be fine. For winter storage, put a bottle of Sta-Bil in the tank and fill it up.

Larry Myers

When traveling in the Vette I do my best to buy 93 octane Top Tier gas. Shell when I can find it. However, in some parts of the country there is a dearth of Shell stations. When that happens I refer to the Top Tier listing I keep in the console.

In the small town I live in, at one point there were five stations selling Top Tier gas. Today there is but one...Shell.

Always on watch for non-ethanol gas but it appears, at least in this part of the country, it's nonexistent.

Like Gary I put a bottle of Sta-Bil in the Vette's tank for the winter.

GMJim

Thanks for the replies. I may be a little paranoid about this but I have a choice of Sunoco 94 octane 10% ethanol or Shell 91 No ethanol. I prefer no ethanol but I think the LS9 needs the minimum 93? I'm going to use the no ethanol fuel for storage but switch to the 94 in the spring. I have never used a fuel stabilizer in any of my cars and have never had a problem. Gasoline is supposed to be stabil on it's own for 6 months. I don't like filling the car with the 10% ethanol fuel and letting it sit all that time. Over time the ethanol which has a slightly heavier specific gravity will sink to the bottom of the tank. A 20 gallon tank filled with a 10% ethanol fuel contains 2 gallons of ethanol. If you don't stir the fuel up before starting the car in the spring you're running on 100% ethanol for the first little while, and longer for a carburated engine that doesn't have a fuel return. Not only is ethanol corrosive but it will have an effect on the way the car runs until the fuel pump return mixes the fuel. There are a lot of issues with the new E15 fuel in cars not designed for it as well so be careful filling up as this fuel is popping up in many places. This small increase in percentage (10 to 15) has the auto manufacturers warning people their warranty will be void if they use it with cars not designed for it, which is why I'm concerned. Running the car for a short period in the spring with 100% ethanol might not hurt but I don't think I want to experiment with my Corvette. If you have a flex fuel car you're ok but I don't think our Corvettes will be compliant for a while.

OnPoint

Altho in my neck of the woods as well as many states, there is no 93 octane available. Only 91. To OP, 93 is great if you can get it, but the ZR runs fine on 91, which all that many states have.

Ballbearingturbo

Corn!

GMJim

If the general consensus with all the ZR1 owners is that it runs good on 91, that's what I'll use.
Thanks

OnPoint

OP, don't put anything higher than E10 in your ZR.

I won't even run on E85, let alone E100 with stock configuration, without mods.

GMJim

Yeah thanks I know. I don't even like the 10% stuff but nobody but Shell has the non ethanol and it's only 91.

OnPoint

Shell non ethanol 91 will run fine.

mirage2991

For long storage put some Starbright in it. Use it on my big block and my boats, it just works, i swear by it. My big block camaro has 6gal of 7 mo old fuel and it still runs near perfection...without it my motor would drop one cylinder and run like crap...really works...use a bottle in each of my tanks on my 35 foot boat who is docked year long...love that stuff!
Lucas make a good fuel treatment which I also use on my other cars, but it's more of a fuel system cleaner....

svtkeith

I use 91 oct got no choice that's all I can get in my area but it works just fine.