So, I've been told you can put earlier heads on a later block but not the other way around Something about the coolant passages or needing to block some. Thoughts ?
That is true about later heads being able to fit on earlier blocks. The earlier blocks have 'single scallop' on the water passage for the middle cylinders. Later blocks have 'double scallops' in the middle cylinders. There is a TSB put out back then that goes into detail as to what will and what won't swap and work. If you have volume 2 of the Guide to GS (Rare Service Bulletins) by Steven L Dove, it is in there.
Yep. Unfortunately, the book is at the shop. Hard to come by now; NOT CHEAP!!! Want a copy of those few pages?
Pretty sure you CANNOT Put later heads on the earlier blocks. Early heads can be used in later. 71 heads are superior to 72 and up which are smoggers.
I just did this. I have 73 heads on my 71 block. Just need to close off the water ports as pictured in Larry's post above. My 73 heads were ported so I went with them instead. This is pretty common and I did a lot of research before I made the call
I tried printing this off and can't seem to read it. Any chance you could email me a high resolution copy? What reference is this from? Thanks.
The two pages that Larry posted are from the Guide to Buick GS, volume one, color edition; Pages 72 and 73. The actual TSB is in the volume two (Rare Service Bulletins) It has one more page that discusses the head gaskets; but Larry's reference is clearer, easier to understand. Just do a "Print Screen", and it should come up. That is what you would have to do from mine as well, probably...
