Cylinder heads 911 / 964

[bergporsche]

Someone knows where the left cylinderhead come from, model!
The right one is just an ordinary C2/4 head from 1990

Casting number is 930.104.326.3r production date 4 -'85.
Looks very simular as the C2/4 head but its different.

Hope that someone knows the answer!!

[Bill Verburg]

production date 4 -'85.

???

The tip off is the 3 stud intake, only used on 964/993 heads

a production date that early means pre or very early maybe '89 production

[VincentVega]

Are 964 and 993 heads interchangeable?