First let me clarify my budget is near nothing, so for all going to say to get vortec or other 350 heads thanks i know its good advise but it is out of the question right now? I just aquired my second camaro 89 rs, it was converted from tbi to a carb 350 but the guy put on 305 heads , and must have ran crap gas cause he blew a head gasket leaking water into oil, what would be the compression ratio for these heads on this motor? And can i run 91 oct with this setup? Also what would be a good matching cam for this setup or the biggest cam that will work with the set up? I will be running a stock quadrajet carb and manifold gasket matched as will the heads plus polishing and smothing out the combustion chambers?
head casting 14102187- 58cc 1.84 and 1.50 valves
the block 350 (4-bolt main) is from a 92 gm 2500 and has what appears to be stock dished pistons with the 4 relief pockets

 

Those are the 305 TBI heads, they're boat anchors as far as performance is concerned. They're called a "swirl" design head, made for low end torque and better gas mileage. And due to the restrictive intake runner design in the casting, NOTHING can be done to make them a good performing head. Don't waste your money trying to "fix them up" with porting/polishing work. Save up a little money and check on craigslist, you might be able to find some reasonably priced good heads.

 

this is going to be a cruising car, maybe eat up some ricers here and there, i am no too worried about the no performance after 5000 rpm, as i wont be in that range, a friend is giving me a 375 hp 350 that has a burnt valve but i dont have money to fix it right now. so the plan is to throw that motor on the stand and work on it as money allows, and to get the motor in the car running again so i can work out some shoddy looking wiring and test out the tranny, i wont be putting in any money to the heads just some time with my dremel to clean up the combution chambers and gasket match them to manifold. So my main question would be what is the highest compression ratio you can run with 91 octane gas, thats the max here unless you spend 5.50 a gal on 100 LL?

 

91 octane is good for just about any member car on this forum. There is no way your setup will call for more than 91. I couldn't imagine your set-up being over 8.5:1 so you will be fine.

A couple of things you stated worry me though. How do you know you have a 375HP 350? How did it burn a valve, and what changes are you going to make to not allow anything like that to happen again? It wasn't bad gas that lead to a head gasket failure.....Also, I would be very careful with a dremel tool on heads. They are going to take a long time to clean up, however they won't take too long at the hands of someone that doesn't know how to port to make bad to worse. Just be realistic with you expectations.