How much boost could I run on a completely stock 305 tpi with 93 octane and not risk detonation? It's 9.5:1 CR with stock 58cc heads. I'm thinking about a turbo.

 

I'm going to say 10psi with an intercooler is the max I'd want to put to that, 6-8psi would be better for avoiding issues at least to start with.

 

i agree 8psi,unless u o-ring the block or use a copper head gasket.Are u using efi or carb? I recomend 4 degrees retard for every pound of boost and 11 to 1 A/F/R at w.o.t,Should control detonation with no problem with that CR.Maybe even 10 psi i just dont know the altitude in mississippi

 

i assume its TPI, if its completly stock 305CI...?
if so id stay at about 8psi, i ran 10psi on about 9.1/9.2:1 on 93octane, (stock 350, felpro stock replacement head gaskestes, only inetrnal mod was a smallllll turbo cam) with an intercooler but also am using a blowthru carb which people claim also cools the boost entering the motor by adding fuel slightly earlier then efi... just my 2 cents.

you could try using water/meth injection and crank the boost up to 15/18ish see what the 305 can do.

oh yea... i have ha dgood luck avoiding detonation by dropping a couple heat ranges on the spark plugs, kinda cheap way to help keep the pistons intact.
good luck