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Don Sofranko · 03-26-2021, 10:08 AM

A friend of mine has several sets he is liquidating from his dads estate.
if anyone wants some 461 heads, I can hook you up, location near Ottumwa iowa.

Good read on the 461 heads and early vette heads
Copied from the vette forum not my words...

https://www.corvetteforum.com/forums...ump-heads.html

The 461X heads are 61-63 ONLY. They ONLY came with 1.94/1.5 valves, and as mentioned, they had about 170cc intakes. PERIOD.
The 461 heads were 64-66 ONLY. They could have EITHER 1.94/1.5, or, 2.02/1.6 valves, depending on engine application (350, 365, 375hp/327). Also, as mentioned, they had about 160cc intakes. If the 461 heads were machined for the larger 2.02/1.6 valves, then the wall of the combustion chamber next to the intake valve was relieved by machining to reduce flow restriction. If they got the 1.94 valves, this extra machining was not done.
Below is one of my 461X heads which I had machined to accept 2.02/1.6 valves and the added machining for relief around the intake valve. The other head is an untouched head with 1.94/1.5 valves. Back in the day, and to some extent, still today, heads (either 461X or 461) which got the smaller valves are machined for the larger 2.02/1.6 valves and also have the extra machining done to improve flow around the intake valve. Of course, porting and polishing is also still done to these early heads. On mine, I only had the intake runners smoothed up to relieve the rough casting.

Debate on power pack, double hump heads, included talk on single and double hump heads. Per the website below, casting numbers are 3917290 and 3927185 for single hump.

Don

03-26-2021, 10:08 AM	#6
Don Sofranko Member Join Date: Sep 2002 Location: Iowa Posts: 121 Likes: 0 Liked 128 Times in 32 Posts	Re: SBC 461 heads A friend of mine has several sets he is liquidating from his dads estate. if anyone wants some 461 heads, I can hook you up, location near Ottumwa iowa. Good read on the 461 heads and early vette heads Copied from the vette forum not my words... https://www.corvetteforum.com/forums...ump-heads.html The 461X heads are 61-63 ONLY. They ONLY came with 1.94/1.5 valves, and as mentioned, they had about 170cc intakes. PERIOD. The 461 heads were 64-66 ONLY. They could have EITHER 1.94/1.5, or, 2.02/1.6 valves, depending on engine application (350, 365, 375hp/327). Also, as mentioned, they had about 160cc intakes. If the 461 heads were machined for the larger 2.02/1.6 valves, then the wall of the combustion chamber next to the intake valve was relieved by machining to reduce flow restriction. If they got the 1.94 valves, this extra machining was not done. Below is one of my 461X heads which I had machined to accept 2.02/1.6 valves and the added machining for relief around the intake valve. The other head is an untouched head with 1.94/1.5 valves. Back in the day, and to some extent, still today, heads (either 461X or 461) which got the smaller valves are machined for the larger 2.02/1.6 valves and also have the extra machining done to improve flow around the intake valve. Of course, porting and polishing is also still done to these early heads. On mine, I only had the intake runners smoothed up to relieve the rough casting. Debate on power pack, double hump heads, included talk on single and double hump heads. Per the website below, casting numbers are 3917290 and 3927185 for single hump. Don Last edited by Don Sofranko; 03-26-2021 at 10:25 AM.