360 Aftermarket Heads on 318
So I've seen some discussion on various forums about stock 360 heads destroying compression on a 318 because of the combustion chamber size being closer to 74-76 ish... instead of the stock 318 size which I have found, from research, to be anywhere between 60-66 cc's. This can of course be minimized by milling down the stock 360 heads somewhere around .040-.050 to fix that.
HOWEVER here's my situation... when I acquired the 67 barracuda (has a 318 from 1970 in it), I discovered it has the Edelbrock 7177 RPM Cam for 340 360 in it that recommends 340-360 heads. Why that was put in a stock 318 with stock 318 unported heads, your guess is as good as mine. I found someone selling various parts including aftermarket 360 heads from Edelbrock, I believe the part number is #60779, that have a 63cc combustion chamber. So the only difference I see between those and the stock 318 heads are the valve sizes.
QUESTION: because this combustion chamber is within stock range for a 318, shouldn't those heads (paired with either the 340 intake that I have now or the 360 intake that also comes with the heads) theoretically give me the airflow I need (per the cam's instruction) without causing the compression ratio to be absolute trash? That should allow me to leverage the better performance from the cam, so I think.... or will the larger valve sizes cause other issues.
Looking for a healthy discussion and to learn me a thing or 2.
attached some specs for the aftermarket 360 heads for quicker reference
So I've seen some discussion on various forums about stock 360 heads destroying compression on a 318 because of the combustion chamber size being closer to 74-76 ish... instead of the stock 318 size which I have found, from research, to be anywhere between 60-66 cc's. This can of course be minimized by milling down the stock 360 heads somewhere around .040-.050 to fix that.
HOWEVER here's my situation... when I acquired the 67 barracuda (has a 318 from 1970 in it), I discovered it has the Edelbrock 7177 RPM Cam for 340 360 in it that recommends 340-360 heads. Why that was put in a stock 318 with stock 318 unported heads, your guess is as good as mine. I found someone selling various parts including aftermarket 360 heads from Edelbrock, I believe the part number is #60779, that have a 63cc combustion chamber. So the only difference I see between those and the stock 318 heads are the valve sizes.
QUESTION: because this combustion chamber is within stock range for a 318, shouldn't those heads (paired with either the 340 intake that I have now or the 360 intake that also comes with the heads) theoretically give me the airflow I need (per the cam's instruction) without causing the compression ratio to be absolute trash? That should allow me to leverage the better performance from the cam, so I think.... or will the larger valve sizes cause other issues.
Looking for a healthy discussion and to learn me a thing or 2.
attached some specs for the aftermarket 360 heads for quicker reference