If some of you remember, I pulled the heads on my '97 Mercruiser 5.7L/alhpaII late last fall. I started a post based on finding the recessed type pistons. I posted a picture along with being confused on the compression ratio. At that time, I assumed that the heads were "standard" heads with 76cc combustion chambers. Given the recessed pistons, that would give a significant lower ratio than what Merc advertised.
Well, I pulled the heads along with the other parts I plan to sell, this weekend. Took pictures and wrote down different part numbers, etc. The heads had a casting number of 14096217. When I did some inet seaching and reading in Dennis's book, these are labeled as 64cc heads. According to Dennis, that casting number was used on aftermarket heads from GM. Essentially high compression versions of the 76cc heads. The same casting number is used on the two different versions of the heads, pre-'87 with normal intake center bolts and post-'86 for canted bolts. They both have 64cc not 76cc. Inet says 285/300hp crate engine heads (64cc).
There is no indication that these heads were installed by the original owner of the boat. I am 99% sure they are stock. These heads would give about a 9:1 comp ratio w /the recessed pistons, that were stock on my engine.
Anyway, to be sure before listing, I am going to try to measure the volume of the chamber, if I can find a cc measuring device around the house. Given I don't have another known head to look at, its hard to tell from visual. Compared to some pics in Dennis's book, but not conclusive. Any GM head experts that could help me ID from other numbers or specific measurements?
Well, I pulled the heads along with the other parts I plan to sell, this weekend. Took pictures and wrote down different part numbers, etc. The heads had a casting number of 14096217. When I did some inet seaching and reading in Dennis's book, these are labeled as 64cc heads. According to Dennis, that casting number was used on aftermarket heads from GM. Essentially high compression versions of the 76cc heads. The same casting number is used on the two different versions of the heads, pre-'87 with normal intake center bolts and post-'86 for canted bolts. They both have 64cc not 76cc. Inet says 285/300hp crate engine heads (64cc).
There is no indication that these heads were installed by the original owner of the boat. I am 99% sure they are stock. These heads would give about a 9:1 comp ratio w /the recessed pistons, that were stock on my engine.
Anyway, to be sure before listing, I am going to try to measure the volume of the chamber, if I can find a cc measuring device around the house. Given I don't have another known head to look at, its hard to tell from visual. Compared to some pics in Dennis's book, but not conclusive. Any GM head experts that could help me ID from other numbers or specific measurements?
