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'78 Protouring
03-03-2011, 03:33 PM
So i have a stock '78 camaro with a 350 TH350 set up and i got a speed prom .50 lift cam with the car when i bought it as well as 305 heads. I Also have a edlebrock single plane intake i can put on as well.I hear that the 305 heads lose power in high rpm. Are there more breathable heads from a older camaro that would help with compression? Ik vortecs are the best but i cant afford them and i read that i would have to grind them to get the cam to work right. Any help is great! thanx!

hifi875
03-03-2011, 05:13 PM
you need a head w/smalll comubustion chambers probably in the 64cc range. the 305 heads are probably in the 72-76 cc range. it would give you close to a point increase.

CanyonKiller
03-03-2011, 06:27 PM
You are correct that 305 heads dont flow well in higher rpms due to the small ports and intake valves. The chambers are actually 58cc and the stock smog heads were 76cc. You could use 64cc heads but the biggest problem is the stock dished pistons that give you ~8.3-1 compression with stock heads.

68Formula
03-08-2011, 03:23 PM
You would have to do the math to see what the compression works out to, but AFR heads with 2.02/1.60 valves and heart shaped chamber are $714.60 each complete. By the time you spend money on old iron heads, new valves with multi-angle cuts, porting, new springs, new retainers, new guides, new valve seats, etc. you'll be into them for about the same amount plus you won't have the modern heart-shaped chamber and they add 50lbs to your front end.
http://www.summitracing.com/compare.aspx

ArtosDracon
03-09-2011, 03:56 AM
You could also look for a set of L98 corvette or camaro heads. 58cc chambers and they flow better than any pre-vortec heads. And the Vette ones are aluminum.