Just picked up a 400 sb in good shape.I was thinking of replacing the cyl heads with something other than stock, dart, world products,
or afr. My concern is can you use heads that are drilled for 400 steam holes on another motor?
Or can you swap them to any SB at a later date?
If they can't be swapped I'll see about getting larger valves for the stock 882,s.

John,
ANY SB heads can physically be bolted onto ANY SB. For example, you can bolt on '56 265 heads onto an '80 400 or vice versa. BUT YOU NEED TO KNOW THIS, ANY PRODUCTION SB HEAD CAST AFTER JULY 74 (for 75-later engines) ARE NOT, REPEAT, NOT A GOOD CHOICE------------That's when Chev started casting them thinner and added a second exhaust crossover passage (read more heat--not good---causes cracks). You can use ANY SB head on a SB400, just be sure to drill the necessary steam holes. If you use a 400 head on a 350, 327, etc, simply use the 350 head gasket---------it will seal off the steam holes just fine.
Hope this helps.

[QUOTE]Originally posted by DZAUTO:
[qb] John,
You can use ANY SB head on a SB400, just be sure to drill the necessary steam holes.
Tom, I really appreciate the quick reply,thanks. I know the swapability ( is that a word? ) of chevy SB heads just needed to know if any heads I bought could be used on another motor at a later time. I,ve read your words of caution on late model heads before that,s part of the reason I'm considering new heads on this motor.

John,
ALL 400 heads were of the 76cc variety and had the largest ports available on production heads. Thus, a 400 head, with 2.02/1.6 valves, flat top pistons and some minor clean up port/bowl blending would be an excellent head on a 350, or even on a 383. You could probably even get by on todays pump gas using 400 heads on a 350 with domed pistons. This would make comp ratio about 10.5 on a 350.

Stock 400 heads came with 1.94"/1.60" valves to help exhaust flow... pdq67

Originally posted by pdq67:
Stock 400 heads came with 1.94"/1.60" valves to help exhaust flow... pdq67 My 400 was out of a '76 Blazer and had the small valves. Even the ports on the heads looked noticeably smaller than those on my 327. Perhaps the trucks got the smaller heads for torque?

You know, GM musta done some weird stuff with the truck motors back in the mid to late '70's!!!

This is about the third thing I have heard about truck heads being different lately.

pdq67