can i just bore my 2.8 out 40 thousands and put some 40 thousands pistons and rings and then buy a crank from a 92 Chevy Cavalier z24
and drop that all in and then just buy 2.8 rebuild kit
would that all work and give me some more power
and be simple enough like would that crank be a perfect fit? i herd it would
thanks
a list of other possible cranks would be nice too
i have a 87 gt 2.8 v6 with a 5spd

[This message has been edited by Byron (edited 06-27-2008).]

Quick answer is "sometimes" I have been led to believe that there are 2 different size crank journals in the Fiero 2.8 engine. One will fit and the other won't. Also you will have to get new pistons as the wrist pin holes are in a different place. If you have a pre 88 2.8 you will have to get a neutrally balanced flywheel/flexplate. I had an 85 2.8 changed over to a 3.1

The difference between a 3.1L and a 2.8L is the crank and pistons. You can buy a "stroker kit" that comes with a new crank, new bearings, new rings and new pistons.
I am not sure which crankshafts from other engines will swap in because as Phil stated, There were two different journal sizes used.

If you want to go with used parts to keep costs down, Just look for a 1990-1991 GM Minivan (Lumina APV, Trans Sport, Stilletto) with the cast iron headed 3.1L and swap over the Fiero intake and ignition system. (You will need an 88 Fiero flywheel/flexplate for it too)

[This message has been edited by Oreif (edited 06-27-2008).]

The 60° V6 engine family got a larger crank main journal size in 1985, so all of them made after that are the same large size, including the 3.1 and 3.4 and all 2.8s used in the Fiero.

On the crank you need the 981 casting, it was used in the Camaro and others, it's the heaviest duty version. You will need to get pistons for the iron-head 3.1, if you use aluminum head pistons your compression ratio will be unusable.

The rods are all the same for all the 2.8 and 3.1 motors and fully interchange.

JazzMan

Yup, just about any crank after 1985 will fit right through the 3.4 (which has the same crank, marked '3.1'

The conversion will give you noticeably better midrange torque and you'll find yourself no longer shifting down when you used to, as the higher gear will pull much better.

I run a 3.2 (3.1 conversion .040" over) in the turbo engine.

BTW, I have seen the so called kits costing more than just a set of new pistons and a good used crank that tests out OK.