[low77ride]

Ok here it goes i have a 1977 monte carlo with a 350 sbc. My friend has 305 heads he wants to get rid of, so what im wondering is it i can just bolt them up to my 350 putting out 8.5:1 compression ? And do i have to up size the ports and valves or can i leave them stock aslo what kinda horse power difference will i be getting? thanks

[Dans83Olds]

A friend of mine has a 350 punched .60 with port and polished 305 heads on his 87 camaro. People kept telling him that he would have detination problems due to the high compression. As to date he has had no problems with pinging. He has his timing set at 4 degrees past stock. he runs 89 octane in the car.

[NorthStar]

Which 305 heads? Theres a few different chamber sizes.
If theyre 434 casting number you could install larger valves and do a pocket port & little unshrouding those would work super for what youre trying to do.

[low77ride]

Yea im not sure the # but if they have 434 casting # i will do so thanks.

[low77ride]

Ok my friend just bought a running stock 350 4bolt main out of a 1984 chevy truck for 350 with carb. Hes transplanting the motor into a caprice classic (X-cop car). The motor leaving s a plane jane 305 (not H.O.). We were wondering what would the stock 305 heads do if we put them onto the 350? Boost HP any at all? Or just break even with what it allready has? Were getting the motor tomorrow so we want to know if this will help any? thanks for the help its greatly appreciated.

[DoubleVision]

the 305 heads will kick up the compression on a stock 350, and the small runners and valves will give it lots of low end power, but it`ll fall on it`s face at 3500 rpm. decent 305 heads are the 416, 440 casting and the 601 castings used on HO engines, the valve sizes are 1.84 intake 1.50 exhaust with 58cc chambers, you can have 1.94 valves added but it won`t be of much help unless the chamber is deshrouded.

[low77ride]

So a set of stock 305 heads will work but at about 3500rpm them will just stop pulling or having any power past 3500? When in lower rpms will the motor shine ?

[mikeweyman]

that combo will give you about 10/1 compression or higher.It will come off the line like a scalded cat, but will die out about half way through the gear. great bottom end would be o.k. in say a 4 wheel drive truck or plow, not a car.
hold the car back in first and see where 4000 rpm is .real quick but not fast.

[malducci]

Some info on the 434 heads - there 60cc chamber - 160cc intake and 57cc exhaust ports. I CC'd them the other day. The set I own have 1.72/1.5 valves - put some 1.94/1.5 valves in them though if you can get it done for cheap.