Hi guys, I accidentally ordered a whole engine gasket kit for a 350 Chevy TPI engine w/ 1pc rear main. I have a 305 TPI engine. I got such an incredible deal on it, with name brand gaskets, that it is not worth shipping back. It has ROL extreme high temp head gaskets that are for 283/302/307/327/350 engines. I know the 305 has a smaller bore, and I will lose a small amount of compression by using a gasket with a bigger diameter cutout for the cylinder, but will everything seal okay? I assume it should be fine. The correct 305 gasket (felpro 8510pt) is 3.900 diameter, 0.041 thick. The gaskets I have are 4.005" diameter, 0.045 thick.

 

I would have to say no. I ended up using regular napa premium brand 305 specific head gaskets when i rebuilt mine. i had ordered a set of metal .015 thin head gaskets because i wanted to gain some compression but i didnt like the extra quench area in the bore. there was just too much of a difference between the 2 sets.. so i say use 305 gaskets.

 

I've got 350 head gaskets on the 305 in my burban, but it's got 350 heads. - anyhow, yes it'll work just be giving up some compression, and leaving a place for carbon deposits...

 

I am running the composite head gaskets for a Vette L98 on my LB9. no issues.

 

Ok cool thats what I figured. I will lose approx .15 compression with the thicker gaskets and larger combustion chamber rings, but I already have the composite gaskets. Grrrrrrrr! I might spring for the actual 305 gaskets, but at least I can use these if I have to.

 

I made the same mistake !
My world heads require 350 head gaskets, but I bought a 305 master kit. I had to go buy 350 head gaskets.
327, if your interested in the 305 (8510pt) gaskets, Email me, you can have 'em for the shipping cost.