NEED HELP on a 2.8 conversion to a 3.1

[g-b8s]

ok so i did research for my fiero gt and the 3.1 from a 94 cutlass can fit in my fiero but what i need help with now is how do i change the heads from a 2.8 to 3.1 without losing comprision ratio or anything that would make it runny worse then b4 if anyone can help me

[Guest]

I don't quite follow what you want to do.

Are you wanting to use your iron heads?

If so, don't worry about getting the complete genII 3.1, just get a crank from one, and order pistons for a genI (1990 to 1993 F-body, 1990 to 1993? Lumina APV) 3.1, and rebuild your 2.8 using these psrts. Make sure you have a 1986 or later block though, as they have the large main journals that are needed to use the later crank.