Here is my deal. I have a 92 base model firebird with the 3.1L V6. I have not done any upgrades to this car yet and I want to start out with a better base than this engine. I am trying to avoid a swap with a V8 though. I am not sure what V6 engine would be easiest to swap with. I would like to avoid a carbeurated engine. My current idea is to use the 3.8L from the 89 models. Does anyone have any experience doing that swap? Is there an easier or cheaper but still powerful swap to do?

P.S. I have the stock auto tranny

 

Any reason against swapping in a tried and true EFI V8?

The old FWD 3.8's arent worth their weight in scrap, dont bother. About the only worthwhile V6 swap is the 4.3 from a light duty truck, but retaining EFI on those is troublesome because the PCMs arent very forgiving and programming is very limited compared to the much more common V8 programs. They also hit a performance ceiling rather early compared to common V8's

A LT1 V8 swap from a Fbody or B-body will be the best out-of-the-box bang for your buck. LSx would be better for the efficiency and power hungry person whos not afraid of the increased upfront cost

 

I'm just trying to keep the V6 because of the better (not by a lot) mileage, lower weight, and because of the other complexitites involved. How easy would the LT1 or LSx swap go?

 

LT1 is easier than the LSX, because it uses SBC motor mounts/trans mounting (IIRC). Youre going to have to do some re-wiring no matter what engine you do, so don't be afraid of either of those two engines. The LSX engines can make ~400hp and still get 20-25mpg (depending on how good your tune is). I've personally got my L98/700r4 up to 26mpg and that's without highway mode enabled. As far as weight, I'm pretty sure the LS1 has a very similar, if not lighter weight, than the iron 3.1 you have in there now

If you stay with V6, go with the 4.3L like some above said. I would not recommend the vortech 4300 from newer trucks - I've seen those throw rods left and right (metaphorically and literally). You could probably get Megasquirt to work pretty well on an old school 4.3L. They make MPFI manifolds for those, don't they?

 

Any idea how much i will have to replace for the LT1 swap? I'm trying to keep the cost down since I'm going to college and only have a part time job. I'm not sure how much other than the motor I will be able to afford come time to replace my current engine at its funeral.

 

Tally up each subsystem and make a parts list for each

 

Than the LSx series is your clear winner. Mileage and power.