Hello guys. Just a simple it bin talked about. I’m just not sure really. I need a Little more guidance I guess I have read forms they say the 99 -04. Then 04 to present are the the best. I was thinking of a swap I have access to a 1998 gpt supercharge. Or a 2007 Gt. supercharge . Is one better than others. Newer models have trouble programming to fiero unless they can do it better now. Just not sure what car or if there a better year ? Thanks 🙏

The better engine is the one with the lowest mileage.

They are easily controlled in a Fiero application.

I was thinking of rebuilding the engine in either one of them before doing the swap

quote Originally posted by Ren1975: I was thinking of rebuilding the engine in either one of them before doing the swap

If you want to have bottom end problems, go for it.

If you don't want bottom end problems, leave it alone.

quote Originally posted by olejoedad: If you want to have bottom end problems, go for it. If you don't want bottom end problems, leave it alone.

what ole dad is saying is a lot of people in here that rebuilt their 3800s had them go bad.that its best to just run them as is.

Why do they have problems if you rebuild the motor. I thought it be better to do that then you know it a new engine and don’t have to worry about it. I just I was wrong.

Rebuilding the rotating assembly on a 3800 isn't as easy as say, a SBC, an LS or a 60° V6.

The 90° V6 engine is inherently unbalanced. Anything out of tolerance and they beat themselves to death.

However, even high mileage 3800's hold up well to abuse.

Renew the oil pan, front cover/water pump, intake, supercharger and valve cover gaskets and call it good.
The intake gasket is known to fail and leak water into the oil - oil in the water has killed a lot of 3800 bottom ends.

Agreed to all above, not just for Fiero's, Google GM 3800 rebuilds and you will see that bottom end is a fickle ***** . Only go as far as head gaskets, replace all the seals and gaskets, it'll run good a Long GD time, probably longer than the majority will drive their Fiero.

Also, once you take that front cover off, be absolutely sure the oil pump primes afterwards, its not a hard process, take 5 minutes or less.

[This message has been edited by jelly2m8 (edited 12-12-2023).]