Any significant differences between 3.1L engine and 3100cc engine

My parents have a 94 Buick Regal. It presently has a 3100 engine in it, which is blown. They were considering putting a another engine in it. I have found several 3.1L engines. Since a 3100cc and 3.1L are the same size? Are there any significant differences in these engines that would make it difficult to place the 3.1L into a vehicle which had a 3100 engine in it?

Thanks for any information on this.

The main difference between the 3.1L MPFI and 3100 SFI engine is the intake manifold. The heads are also slightly different. I would assume the computers are different because the 3100 has a Mass Air Flow Sensor and no Manifold Absolute Pressure (MAP) Sensor and vice versa applies to the 3.1L.

You could just do a computer/ECM swap to remedy this. This is easier said than done because your '94 Regal has an ECM controlled transmission (4T60E). I'm also pretty sure that you must use a Buick ECM because your 4T60E transmission is from a Buick - your Regal. So you'd have to get a computer/ECM from a '93 Regal 3.1L because that is the only instance in which Buick mated a 3.1L with the 4T60E (1993 Century and Skylark only came with a 3300 V6 engine). You'd probably still need to do some custom wiring to make that work after all that.

It will be harder to find a 3100 from a Regal because the 3800 was installed in the great majority (about 80%) of 1994-95 Regals. Luckily, other 3100-powered W-bodies (1993-95 Olds Cutlass Supreme, 1994-95 Grand Prix, 1995 Lumina & Monte Carlo) are much more common and should work with no necessary mods or ECM swaps.

I hope I didn't confuse you. Good Luck! :)

when you see 3.1L engines for sale, just find out what year it is. A lot of people list 3.1L because it means the same as 3100, so if you get one, just make sure it's made after 94.