72 350 4bbl heads VS. 74 350 2 bbl heads??? Are there any differences between the heads and would I have any problems running the 72 heads on a 74 block??? Would there be any performance improvement??? Also, would the 72 4bbl intake be better to run than a 75-79 4bbl intake???
Basically, no real difference between any of those years/parts... Just more emissions crap on the later stuff, but that can be pluged off,,, or used if you desire. I'm not sure exactly what year they started putting the EGR "hump" in the exhaust ports, but avoid them, unless you can port them out... Then the later heads are a better choice due to harder valve seats. No difference whatsoever between 4V and 2V heads on any year or model buick 350
I found a 72 350 4bbl motor at the local U-Wrench-It yard...I went ahead and grabbed the intake today, since I saw that it didn't have an egr valve port on the intake whereas my later model intake does...Figured since I was going to block the egr off anyway, it would be easier just to get the intake that didn't have it to begin with!!! :Smarty: As for the heads, I debated whether to pull them at the same time, but unless I'm wrong, I didn't think that the combustion chambers changed sizes between 72 and 74(heads that I already have) and even if there was a compression difference, it would've been because of shallower dished pistons and not the heads... And I pretty much already had heard there was no difference in the heads between a 2 bbl motor and a 4 bbl motor, I just wanted to hear it again to make sure o No: My original 74 2 bbl intake has the air injection rails(smop pump crap) cast into it...Is there anything on the 74 heads that I need to do when putting the 72 intake(no smog pump or egr crap) on??? The motor will be going into an 86 Toyota 4x4 pickup and there is no emmisions testing here in the area (yet)... Thanks for any more info you can tell me, oh wise 350 enginemeister!!! :Brow: :laugh:
The 72 heads will work on the 74 block with no problems. The 73 up 350 heads have 2 extra water passages that must be plugged if used on 72 or earlier blocks. There is no difference between a 2 barrel and a 4 barrel 350 head. Jim Burek
