Question about engine fit?

(2012-02-04 15:20:20)

1. hww22 Says: I'm putting a Chevy small block 383 and turbo 350 transmission in place of a Buick 231 v-6 and metric 200 transmission in a G body(81 Cutlass). The shops say everything will bolt right up but even though the transmission looks similar I was told that the trans mount is 6" further back and to just use the factory holes that are open to move it back further. My car only has one set of factory trans mount holes. Anyone have any experience with this?

2. chevyraceman_383 Says: Is it the th-200 3 speed or 200 4r 4 speed auto?

The th-200 has the mount in almost the same place as a th-350

Th-350 face to mount is 20-3/8"
th-200 face to mount is 20-1/8"
200 4r face to mount is 26-7/8"

th-350 and 200 share the same 27-5/8" overall lenght. The 200 4r is 27-3/4" over all lenght

The 200 4r will have trans mount at very rear of tailshaft.. Where the th-200 and th-350 will have mount in common place right behind trans pan.

3. monkeyboy Says: The early g-bodies (like your '81) don't have the same mounts on the frame. Somewhere around '83 they started putting the second set of mounting holes in all the cars, since the 200-4R was first installed in 1983. The crossmember is different as well. But 350 and TH200 as indicated are similar.

4. LadyTune Says: Previous question are right, yes indeed you will need to do some mods to that to make it fit, however they are minimal, you should not be worry about it.

However I think you are overlooking Gear Ratios, I think they could be a bit under optimal with this mod, you can use a simulator to virtually do the swap and find out if another final drive could help you, give a try at http://www.nxgtrsim.com

5. bandit_60 Says: on each side on the frame where the transmission cross member bolts up take the bolts out, side the cross member where you need it to be and drill new holes in the frame. they might be right but i doubt that the chevy engine will bolt to a buick or oldsmobile transmission.