Which is easier? and what problems will I be looking at. Oh and can someone post the specs of the 3.1 compared to the 3.4? I need a side-by-side aspect. Thanks!

The 3.4 swap will be far easier than the 4.3 because the 4.3 uses a different bolt pattern for the bellhousing and different motor mounts.

in your state you dont have inspections right? a 3.4 is like 2 grand and for a little more you can get a 350 and a turbo 350 trans for your car. screw the 6 cyl unless you need gas mileage

I don't think we do inspections here in MI, we do to an extent, but not swapping motor wise, as long as it's clean it's good. i am actually wanting the 3.4 for the gas mileage, plus there are more bolt-ons for the 3.4 than there is for the 3.1.

any bolt on for a 3.4 will work on a 3.1

Are you srious? ANY Bolt-on for a 3.4 will fit onto a 3.1? I think you just made my day a whole lot better, so if that is the case why do people b*tch about not having V6 headers when RKSport has ceramic coated headers for the 3.4?

any external bolt on should be the same the 3.4 was marketed as a direct replacement from GM for the 2.8 and 3.1 engines(any year)

Well, not exactly. No manual fuel pump provisions on the 3.4 (no problem there), oil pans are different (but will swap from the 3.1).

The 4.3 would be harder than a V8 swap. I'd certainly go 3.4, or 5.0 or more.