Looking at 94,95 Oldsmobile supreme convertible, anybody have opinion on the 3.1 or the 3.4 six , or those cars in general thanks.

 

3.1 is way easier to work on.

 

The 3.4 is a "run away, run away now" engine. This is mainly due to the service issues for the timing belts typically needing replacement every 75k miles, and having to pull the engine in order to do it.

 

I did timing belts in both my 93 and 94 cutlass with the 3.4 DOHC engines. It was NOT easy but I didn’t have to pull either engine out. 3.1 is easier to work in but the 3.4 definitely has more get up and go. If you are a good mechanic go with the 3.4, if not so much than the 3.1.