Hi all

I recently purchased a 1985 Buick Le Sabre Limited sedan in cherry condition. I am thinking about tearing out the 307 and putting in a LS1 or LT1 350 if I can get my hands on one. Can anyone tell me if these newer motors will mount right in or will i have to make modifications? I know the 1995/6 Roadmaster came with some of these motors, and the Roadmaster I think had the same frame as the old Le Sabre.

I would also consdier a Vortec 350 from the 1995 on up Chevy/GMC pickups. Or even a 1970's oldsmobile 350 (this one i know will fit right in, along with the 200R4 transmission)

My questions are would be what can I expect to pay for a good used or rebuilt motor from the list above? And how much to install it?

I am also wondering if the 200R4 transmission is worth rebuilding? I am told it can handle most smallblocks and even some high performance big blocks if set up right. I do not plan on dragracing, and would prefer to stick with a smallblock. I would also like to stick with an overdrive transmission to get the good highway fuel economy.