From what I understand , Mark 5 & 6 will not work on the older Mark 4 . The water holes on the newer heads are larger towards the valley and they don't align properly . Most after market heads will work on the Mark 4,5,6 .
Does it work, or are the water passeges different? Can I bolt up the new heads on the old block with no machining? I see these new take off heads for $450 all the time. I'm getting interested.
Disco
From what I understand , Mark 5 & 6 will not work on the older Mark 4 . The water holes on the newer heads are larger towards the valley and they don't align properly . Most after market heads will work on the Mark 4,5,6 .
put the money into a set of merlins or equiv.
No they won't work. Good book out called BIG BLOCK CHEVY MARINE PERFORMANCE (order at 626-675-3548) will show you the reason why they won't fit.
Dennis Moore:
No they won't work. Good book out called BIG BLOCK CHEVY MARINE PERFORMANCE (order at 626-675-3548) will show you the reason why they won't fit.Yes it is a very good book...I have it. Glad to see ya here Mr. Moore, hope ya will answer some of our questions.