does anyone know the cc of a stock 1977 camaro 305 combustion chamber? is it 72cc? the reason i need to know is because i need to raise my compression and i might be able to get heads off a 305 tpi. does anyone know the cc of the combustion chamber of the iroc tpi motor? im building up a 383, but until i can afford to do that i want to get as much hp from my 305 as i can.

Both will be about the same chamber size. ~58cc is the size of most 305 cylinder head combustion chambers. The heads I took off my 78 305 Malibu's original 2bbl engine were 1.72/1.50 valves (because I still have them in my basement and I measured them myself) but I never bothered to cc the heads. You can get the casting number off the heads (under the valve cover cast into the valve deck) and check it out over on Mortec.com. Real good chamce, though, they're around 58cc.

Heads off a later 3rd gen Camaro will be 1.84/1.50 valves and ~58cc chambers.

So, not much change in compression, but bigger valves and I can thell you overall, the TPI units are better heads. Better ports, bigger valves, better chamber design. Those TPI motors had higher compression than your 305 becuase they had pistons that were either flattops (up to 86 in TPI motors for 9.5:1 compression) or with a very slight dish (87-up in TPIs for 9.3:1 compression).

I believe the compression on your current 305 is officially listed as about 8.5:1. If you pop off a head you will find heavily dished pistons underneath (I did in my 78 305). So there's not much you can do easily to raise your compression with a head swap, but a set of flattop pistons will get you up to a much more reasonable mid-9s compression ratio. Heads on 305 TPI motors were either '416" castings up through 1986 or '081' castings from 87-up.

The combination of the TPI heads, a little bit of a performance cam and some flattop pistons can make an eye-opening difference in your 305s performance. A small 4bbl and a decent exhaust are really needed, too- the stock 2bbl intake and exhaust system are both way too restrictive for performance use. So it's all do-able but it basically amounts to rebuilding the motor. At which point you might start asking yourself..... why not just put in a 350?

Both will be about the same chamber size. ~58cc is the size of most 305 cylinder head combustion chambers. The heads I took off my 78 305 Malibu's original 2bbl engine were 1.72/1.50 valves (because I still have them in my basement and I measured them myself) but I never bothered to cc the heads. You can get the casting number off the heads (under the valve cover cast into the valve deck) and check it out over on Mortec.com. Real good chamce, though, they're around 58cc.

Heads off a later 3rd gen Camaro will be 1.84/1.50 valves and ~58cc chambers.

So, not much change in compression, but bigger valves and I can thell you overall, the TPI units are better heads. Better ports, bigger valves, better chamber design. Those TPI motors had higher compression than your 305 becuase they had pistons that were either flattops (up to 86 in TPI motors for 9.5:1 compression) or with a very slight dish (87-up in TPIs for 9.3:1 compression).

I believe the compression on your current 305 is officially listed as about 8.5:1. If you pop off a head you will find heavily dished pistons underneath (I did in my 78 305). So there's not much you can do easily to raise your compression with a head swap, but a set of flattop pistons will get you up to a much more reasonable mid-9s compression ratio. Heads on 305 TPI motors were either '416" castings up through 1986 or '081' castings from 87-up.

The combination of the TPI heads, a little bit of a performance cam and some flattop pistons can make an eye-opening difference in your 305s performance. A small 4bbl and a decent exhaust are really needed, too- the stock 2bbl intake and exhaust system are both way too restrictive for performance use. So it's all do-able but it basically amounts to rebuilding the motor. At which point you might start asking yourself..... why not just put in a 350?

ok thanx... i had a guy at work tell me they were around 58cc but i wasnt sure so i had to ask. looks like im going to have to save my pennys and put in a 383