Heads needed for sbc


mrl
01-01-2005, 02:11 PM
Happy New Year!

I am looking to buy iron heads for a basically stock 283. The heads that came off the block are low compression(72cc) small valves(1.75/1.50) and runners. I was told by my cam supplier that the best combination for my application(3000 lbs. vehicle, basically street use, low-mid torque, standard shift, 3.5-3.7 gears) would be 60-64cc heads, to achieve around 9.5 to 1 compression ratio, 1.94/1.60(or 1.50) valves, with decent sized runners. Ideally, a set of heads with a casting like 186 or 187 would probably be good.

I have a few questions, please excuse my lack of technical knowledge for the following:
-Since this engine is an early 283('60-'62), can I install later type heads, like from a 305HO, or even vortec heads for that matter?

-Can reverse flow heads be installed on a "early" engine?

-There seems to be more 4" bore heads with 2.02/1.60 valves available. These would physically fit on my 283, but I was told that since the 283 has a 3.875" bore, this would not be a good idea. I thought all GM sbc heads had the same combustion chamber width, since certain castings were found on both 283's and 327's. I am thinking maybe it is because the edges of the larger valves would be too close the the cylinder wall.

Your comments and suggestions would be greatly appreciated.

mrl

jonnyboy9012
01-03-2005, 01:19 AM
Well i dont know if you cant get the exact casting you want, but have you checked brodix, they have a wide selection of heads. Oh, also check out www.jegs.com or www.summitracing.com, they have a good selection of heads for a wide variety of engines.

MrPbody
01-05-2005, 01:33 PM
All the factory 283 heads used 1.72s and 1.5s. If you open the valve size up too much, the cylinder wall DOES get in the way. While the valve may not actually touch the deck, the flow is hampered by "shrouding" of the path.
The "601" 305 head wouldn't be a bad choice. It has a 58 CC chamber (nominal) and 1.84" intakes. A pretty good performance head for a budget. If you use the early 305 heads, all your manifolding will fit.
Yes, the bolt pattern for all the later stuff is the same. The heads will physically fit. You must use all the later manifolding with them.

mrl
01-05-2005, 02:18 PM
All the factory 283 heads used 1.72s and 1.5s. If you open the valve size up too much, the cylinder wall DOES get in the way. While the valve may not actually touch the deck, the flow is hampered by "shrouding" of the path.
The "601" 305 head wouldn't be a bad choice. It has a 58 CC chamber (nominal) and 1.84" intakes. A pretty good performance head for a budget. If you use the early 305 heads, all your manifolding will fit.
Yes, the bolt pattern for all the later stuff is the same. The heads will physically fit. You must use all the later manifolding with them.

MrPbody,

Thanks for your reply. We have "talked" before. I own a 62 Pontiac Stratochief, Canadian, eh! I was told by others also that a 305 head would be a good choice, however I am conserned that 58cc might bring my compression up too high(I calculated almost 10:1) and that 62-64cc would put me around 9.5:1, considering deck heigth, valve reliefs, head gasket thickness. Does this make sense?

Marty

p.s. If you follow hockey lately(juniors championship), I am glad we kicked the crap out of the Russian team to avenge team USA's loss to them. Not much taunting by the Russians in the final, eh? I'll bet some of those poor guys are quite sore today, both physically and emotionally...toooo bad! :lol:

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