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1969 Chevrolet Camaro - reverting to street use from drag

Bought a camaro that is a drag car and uses racing fuel. Would I be able to use higher octane fuel like some stations sell around 100 and be ok. Reverting it back to a street car. 69 camaro

Impossible for us to know the answer to that question based on what you’ve told us.

I’ll assume you are in the USA, if you are not, the 100 octane will not work, period.

Ask the seller the engine’s compression ratio and look to see if it has iron heads or aluminum ones. Tell us the size of the engine.

A big block Chevy engine with greater than 11:1 compression and iron heads will burn holes in the pistons with 100 octane unleaded fuel. And your wallet, because around here that is race fuel costing $10 a gallon.

An 11:1 aluminum headed small block is marginal with 100 octane fuel as long as the car runs reasonably rich. Since it was a drag car, it IS running rich.

You know this car is likely going to run pretty poorly until you modify it for street use, right? Figure 7 miles per gallon, spark plug fouling, bad idle, won’t cool itself in traffic, won’t run when cold. And highway use is nearly impossible if it has numerically high gears and a 3 speed automatic with high stall convertor.

The high compression, race-cammed, race-carbed engine needs at least new heads and cam to make it run acceptably on the street. Same for much of the suspension and wheels and tires tuned to the dragstrip. All the stuff that makes it a drag car has to come out. You bought a body shell, not a street car.

It’s a 355 with power glide transmission and stall converter. Definitely have lots to do to convert to street but was hoping not to have to replace or rebuild engine immediately. Pretty clean car otherwise. Don’t know much yet to compression or heads yet

With 4.56 rear gears maybe? The Powerglide with a high stall convertor will make a TON of heat in the transmission and that heat will all be paid for at the gas pump. Probably be spinning 4000+ rpm at highway speeds. I’d suggest swapping the trans for a 700R4 with much tighter convertor and replace the rear gears. 4.10’s with an 700R4 will give reasonable highway RPM’s but your mileage will still be pretty poor.

Don’t know where you are located but if you have emission testing that is going to be another expense to put this on the road. Plus you might need to check with the DMV for other things you might need to do . You might find out that the cost and effort might be more than you want to spend.

It has 11-1 forged pistons with cast iron heads with 2.02 valves

I think you should be OK with 100 octane no-lead (in the USA). Modern cars can run that high with 87 octane (my 5.0 DOHC Mustang V8) but they have computer controlled fuel injection and ignition and aluminum heads which help draw heat out of the combustion chamber.

Lots to do but worth it as it’s a pretty clean z28.