I need to find out (asap, that's why i'm posting now instead of trying to look up my casting #'s) what kind of ports (oval or rectangle) are on my 1979 gmc 454, out of a 3/4 ton suburban. Was there a standard for this kind of truck?
Thanks
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I need to find out (asap, that's why i'm posting now instead of trying to look up my casting #'s) what kind of ports (oval or rectangle) are on my 1979 gmc 454, out of a 3/4 ton suburban. Was there a standard for this kind of truck?
Thanks
oval
Cool, just curious but what's the basis for that? 2 bolt or 4 bolt?
Well as far as I know (insert 2 cents) there were no IRON rect's between 71 and 91 save the service replacement ones, as for the 2 or 4 bolt, could go either way, get some #'s and post .
79 was most likely the "peanut"port head, small oval port. Great for low end torque, but dont flow very well for any kind of performance use over 5000 RPMs.
can anyone suggest a new set of performance heads? I am slowly turning this thing into a drag car and am going with a 1050 dominator, is oval or rectangle ports more effective for upper range power?