82 Firebird Trans Am octane gasoline

[Rick Longoria]

Hello. I have a 1982 federal firebird trans am with a 4-barrel carbuerater. I live in California. It has the stock 8.6 to 1 compression ratio. I was curious as to what type of gasoline I should put in it(87, 89, or 91 octane gas? I want performance, so is it true that the higher octane rating would be better for my car?

Thanks................Eric

[Trash man]

higher rating just means its less likey to detonate be4 the spark goes off. if its stock just run 87 or 89

[ryan34]

actually too high of an octane can hurt performance. If i run 93 in my car, then i get backfire So i just use 89 and works nicely.

[Joe 1320]

I want performance, so is it true that the higher octane rating would be better for my car?

No. In fact your car will most likely run better on 87 octane. The higher octane fuels are used to slow the combustion process so that the combustion event pressure doesn't expand too soon, causing detonation. Even when you add modifications which increase cylinder pressure ie. increased compression ratio, camshaft, etc. stay with the lowest octane possible without knock. In your case 87 should be just fine. High mileage cars tend to need additional octane due to a buildup of carbon in the combustion chamber. This creates hot spots that cause pre-ignition. using seafoam available at autozone will remove the carbon depositis in the combustion chambers, reducing the octane needed. When I picked up my 89 Deville, it was already at 150K miles and would knock unless premiumn fuel was used. Seafoam cleaned it out and now runs just great on 87 octane and now has 212K miles. Fuel mileage will be better too.