58cc heads VS. 64cc Heads

Hey, me again. Have another question for you guys. Looking to build up my smog engine. I have stated before that a friend of mine has a set of done #370 heads . They are 64cc off of 69-70 car/truck.1:94 1:50 valves. Anyway the reason I was going to put them on my engine was to increase the sorry 8.2 CP. I cam accross a set of done 58cc heads on ebay. ITEM NUMBER 8030999267. They are also done and have the same valves.Check them out. I wonder which set would benifit me best. Remember, I am only building a street engine. Just need some more power and don't want to spend the big bucks. How bout your opinion Tech Inspector.???

I don't know what the "370" heads are, no info. Check the number again.
The ebay heads are casting #601, '78-'86 305, flow a dismal 165 cfm @0.400" lift. Their only saving grace is that the seats are hard.

I had a set of 58cc 305 heads on a 350 trying to increase comp and I could never get the thing to stop pinging. I actually detonated a couple of pistions out of it. Broke the ring groves right out. Even 93 octaine would not stop it. If I retarded the timing so it would run quiet it had no power.