ntsqd wrote:
Entirely different application, but I had thought to use a FWD engine/trans combo installed longitudinally. ... The compound reduction would require something that rev'd along with the tallest diff ratios that could be found.
If you can live with an automatic, the GM 4T60 is your huckleberry: just weld up the planetary gears in the last output stage and you eliminate the final drive reduction. Output is 1:1, just like a regular longitudinal transmission.
The 4T60, 4T80, and related transmissions have the "corporate V6" pattern, and will accept most GM fours, (including the Quad 4) 60 degree V6s (including the Chevy 3.4 DOHC) and the 90 degree Buick 3800 supercharged, and a couple versions of the LS series V8s that were used in transverse applications. Some Isuzu and Honda engines also share the same bolt pattern.
Turned longitudinally, the output shaft centerline is nine inches from the crank centerline if I remember right. A slight engine and shaft offset would probably be desirable. The 4T60 uses a HyVo chain between the crankshaft and transmission; there are various ratios available, and many of them can be flipped giving a range of underdrive/overdrive options.
I had planned on using one with a turbo Buick V6, but my wife wanted to use the driveline out of her old Geo, and I have a pile of Geo spares, so Geo it is...