help

[goatnipples2002]

I have dwindled my list of swaps for my 85 gt down to a caddy 4.9, sb 350, or just build the 2.8 and make it bullet proof and run a 125 shot.

[russianyuri]

Originally Posted by goatnipples2002

I have dwindled my list of swaps for my 85 gt down to a caddy 4.9, sb 350, or just build the 2.8 and make it bullet proof and run a 125 shot.

350 is the easiest, and it will handle a 75 shot stock most likely

[goatnipples2002]

Originally Posted by russianyuri

350 is the easiest, and it will handle a 75 shot stock most likely

the stock 2.8 can handle a 75 shot at the most, but a stock 350 or any v8 for that matter can handle 125 shot.

[MrPbody]

The 2.8 block is inherently weak. They tend to crack internally and put oil in the water. The 3.1 block for FWD cars, '90 and newer, is parametrically identical, but much stronger due to changes in the methods of casting. I've done several 3.1 swaps for P-bodies (now you know where the nickname comes from...).
By upgrading to the 3.1 crankshaft, you get more cubes, and a stronger unit. It is also internally balanced, unlike the early 2.8s Fieros were equipped with. I believe the '88 was the only one with DIS and internal balance. The balancer (Fiero-specific) has no weight in it, so you can move it to the 3.1 without issue. The flywheel is also not an issue, as the one that fits all 2.5, late 2.8 and 3.1 fits, and is internally balanced as well.
With some judicious porting and using larger valves, milling .040" off and using good pistons, combined with small journal small block aftermarket rods (with the bearing tang moved to center the bearing), and Speed Pro rings, you can easily build a 3.1 to handle a 100 hit or more. My 3.1 '86 made 190 RWHP, without nitrous. Now this can be a bit misleading, as Fieros don't follow all the rules. The same engine in an S-15 wouldn't make more than 155 RWHP.
My little P-body made a believer out of more than one JapCrap 300ZX (non-turbo, of course). Same with other non-turbo 6 cylinder Jap cars. I got smoked bad one night by an RX-7, but it had been "enhanced". When it was murdered (crashed by a 16 year old kid darting out into the road in Mommy's Exploder), it took the perpetrator out with it! Yup, broad-sided a '96 Ferd Exploder, near perfect T-bone. Wasted the right front of the P-body, but bent the Ford so bad, the kid couldn't get out the front, had to kick the rear passenger door open. Both doors on the Fiero were still okay.
Anyone says P-bodies aren't tough, hasn't run into one yet...