Which fuel option to use?

[lukeh]

I have a mildly/moderately modified 88 930 cab. Our state is trying to force the 10% ethanol down our throats. I live on the border of two distinct fuel areas. One has nothing but 10% ethanol based fuel including the 93 octane premium. The other area has no ethanol in there premium but they only offer 91 octane premium.

Here is my dilemma. The mechanic says I need to run the 93 octane. However, I've also been reading that ethanol is bad for CIS. Especially a car like mine that sits the 4 winter months and for a week at a time as I only live 1 mile from work. As I can't buy 93 octane without the ethanol I've thought of a few options. Does one of these make more sense than the others?

I can run the 93 octane with ethanol but always add the newer Stabil green that is designed to help with ethanol related issues. I could use the 91 octane and then mix it with the race gas that is available for $6 a gallon at a pump just a few miles from my house. Could this race gas have lead in it (station doesn't know) and could that lead mess with my car. I don't run a cat. if that matters. Another option might be to run the 91 octane and use some other product to raise the octane level. Would that make more sense than mixing with the race gas? Which option would you use or maybe you have a better idea. Thanks.

[Steve@Rennsport]

You need octane and 91 isn't even close for a 930 like yours.

Run the 93 and use Stabil as required. Keep the fuel tank completely full during the winter months to avoid condensation and you will be fine. Change the fuel filter annually.

[docrodg]

Ethanol shouldn't negatively effect the engine provided you do as Steve said for the storage months. IT could drop engine performance just a tiny amount according to some studies. Here are some interesting links:

http://www.psfc.mit.edu/library1/catalog/reports/2000/06ja/06ja016/06ja016_full.pdf

Alcohol for Motor Fuels