I have a chance to grab up a very fresh set of pro built, ported and polished 400 heads. Will these fit onto my 350, and or what will I have to do to make them work properly. I am currently finishing up my new motor, and am using the crappy 624 heads. From what I have been told, almost anything would be an improvement over them. I thought I read something about steam ports needing to be plugged????? I only have a day or so to make a decision so any replies would be greatly appreciated. I dont know the casting numbers, but they were on a circle track car my cousin wrecked the first time out.

 

Yes, you can use them. No need to worry about the steam holes, just pretend they aren't there. If the chambers were enlarged around the intake valves, for de-shrouding, to match a 400 head gasket, then you'll also need to use 400 gaskets, but again, this isn't a problem.

 

400 heads? why waste your time on some (most likely) crappy casting regardless of how "pro built" they area?

 

Stop bashing poor enthusiasts! Probably 10% better flow, ( if the porting was decent) for the price of a few gaskets. Plus 624s ALWAYS crack. Sooner or later, they ALWAYS do.