question on head exhaust port size

MobileCustoms said
Can't you just use the larger port headers and get exhaust gaskets for a 360 to seal them up nice??? Maybe I'm missing something but I just swapped out a 318 for a 360 in my van and went through some of these questions in the midst of it. The 360 gaskets sure looked they would fit and seal right on my 318 heads no problem. The factory manifolds had the larger 360 style ports but were bolted on my 318 and worked just fine.
That way, you leave yourself open for a possible upgrade to bigger heads in the future also.

360 gaskets will fit no problem but they almost exceed the 318 exhaust sealing surface. Like I said before, some FABO members have said that they get them (340 manifolds on an older 318 head) to seal up. But I didn't want to take any chances and besides the 302 heads had bigger ports and a closed combustion chamber. If the OP can get them to seal up then he's in the clear!!
In my case I wanted better exhaust manifolds and getting bigger ports didn't hurt either.

treblig