When to run Racing Fuel?
 

Im putting together a pretty much stock 350. My question is how high of compression ratio can i run with out racing fuel?

you can get away with 10.5-1 comp with 93 octane if you tune it correctly. otherwise I am running 13.5-1 comp and I am going to be running E85 pump gas safely because e85 is equal to ~105 octane.

You don't need high compresion to make HP for the street. You can build 600HP with 9:1 compresion. You just look for the HP through better heads or stroking the engine for bigger cubes or power adders .

V8Fiero- I never knew that about e85? I googled it and you're right. It says you have to make changes because e85 is highly corrosive to fuel systems. what changes are you making?

Didn't mean to hijack thread but that's interesting.

Racing Fuel
 

The 350 i have is stock (std bore) with a mild cam. I have a set of 305 58cc heads. The cast pistons i have will give me a comp of 10.33 Will set up work? Do i need to run racing fuel?

as long as you tune your ignition and carb good you should be able to pull off 10.33 with 93 octane pump gas.

E85 (ethanol) is less corrosive then the drag racing alcohol (Methanol) so you just have to replace the 20-year old rubber hoses and clean out your gas tank and you should be good to go. I am going with braided stainless steel lines just for that added safety, and Im running an aftermarket fuel pump.

the nice thing about e85 around here is that it costs $2.20/gal... sure beats $6+ for c16 race gas to be able to run with that kind of compression.

also, are you taking into consideration your head gasket thickness when you calculated 10.33? you might end up with a little less or more depending on which gasket you choose.

Racing Fuel
 

Im not sure if they caculated the head gasket thickness. Thats just what the SEALED POWER website said, that i will have 10.33 comp. I will be a a 2 barrel carb.

E85
 

I have been told that you must also remove the foam in the fuel cell as it will dissolve with E85. Can you verify if this is the case, or is it a new myth?

Also...
 

I am going to run in a street stock class at my local short track. All engines have to be stock (so they say). As far as the pistons i have are cast. The 350 block i have has more wear, and should have been bored. But noo money kept me from doing that. I was told with a worn block i need to run cast pistons because they can handle the extra clearance. Hyperutictic pistons can not have much tolerance, in the block walls. I dont know that just what i was told. Im a rookie driver and engine builder.....