Thread: Difference between series 1 and series 2

The series 1 and series 2 are quite a bit different, no way the series 1 top end would fit the series 2 bottom, even the decks are different heights. Swapping the entire engine is possible, though. 3800pro should have some info on it.

you might as well swap the trans as well, the 4t60e is weak. You would also need to convert it from obd1 to obd2. There would be alot of work cut out for you...it would be a cool project though.

I doubt it, my series1 riviera that i had and my gp are like night and day of difference. I believe u might need a series II harness

as i said, its all different. The series 1 has an m62 s/c and is obd1, the series II has an m90 s/c and uses obd2

Easiest way to do it would be get a harness that puts the pcm under the hood. Most Riv's retained the pcm in the passenger compartment while most other cars went to the engine compartment for the series 2's.

Swap engine, trans, and wiring harness. Then make an adapter harness to interface between your engine bay and firewall connectors. Connect only the wires needed like speedo, cruise, gauges etc.

Basically you'd map out the two harnesses and determine what needs to be connected. Probably about 10-15 wires.

I know that I kinda make it sound easy, but when you really get into it, it's not tough. I've also done this type of thing as well as converted a 96 Riv to a 4T65 by adding 5 wires into the harnesses, changing the trans connector and swapping the pcm to a 97 for ease of programming.