Question: Iron or Aluminum?

[CharlesBrown]

What material was used in the 35th anniv. (1988) C4 cylinder heads?

 

[boomdriver]

pretty much everything from 87 up is aluminum. Some 86 have iron.

 

[BADDUCK]

The 1988 was the first year of the 113 "D" port aluminum heads.

 

[CharlesBrown]

thanks guys!

 

[GRAND SPORT #12]

early 86 have iron because cracking issues at the attachment boss then was worked out in 86 to make debut of the convertible so then aluminum was used

 

[BADDUCK]

'86L and '87 were aluminum but a different casting #128