1baker11 submitted a new Garage Item: 1991 Buick RoadMaster EstateWagon Read more about this garage item here...
Probably a 3.23. They did not come with a 3.08 in 91. You had a choice of a 3.23 or a 2.73 that year. My 91 OCC has the 3.23 and my 92 OCC has the 2.73.