Tschim

Hi, Are the aluminum heads on a 69 L88 (430hp) the same heads that would be used on a 69 L89 (435hp), or would they have different casting numbers? I see they also made the exact same head for 71 LS6 (454). Did all of these heads have date codes on them? Thank you

Tschim

Additional question, is the date code on the top of the head and visible or on the bottom of the head, meaning you would need to pull it to see it? Thanks

Rowdy Rat

"Tschim,"

The 1969 L-89 Corvettes (as well as all 1968-1970 L-89 applications) used a closed chamber aluminum cylinder head with casting number 3919842.

For first design 1969 L-88 Corvettes (as well as 1968 L-88 Corvettes) used this same closed chamber head (3919842). First design L-88 engines are broadcast coded "IT".

Second design 1969 L-88 engines (as well as all 1969 ZL-1 applications and 1971 LS-6 Corvettes) used and open chamber aluminum cylinder head with casting number 3946074. Second design L-88 engines are broadcast coded "LO" (M-22 equipped) or "LV" (M-40 equipped).

Edited to add that the casting number on these two cylinder head castings can be viewed with the valve cover removed, but the casting date is on the combustion chamber side of the head and as such, the head must be removed from the engine to read it.

Regards,