Subaru drivetrain/engine for mid engine conversion

[Eversor]

I'm looking into possibly trying to use the old wagon GL drivetrain and engine from the 80's to power a baja bug.

 

Any thoughts? Will this old drivetrain work with me or be a royal PITA?

 

Basically want to run a mid/rear engine wheeler with 4wd. Will the transaxle and rear diff cooperate with being flipped?

[MilesFox]

I have heard of these ideas and thought of them myself for a trike application. I believe the gears will hae to be reverse cut for a flip. The ring gears share dimensions with NISSAN manufacture as well.

 

I dont know the specifics, but f you know to look at nissan parts for the soob trans, that might get what you are looking for.

 

go with the 5spd trans from 85 and later gl subarus

[Eversor]

on the gears being cut will that be something really noticable when i mock up the components as to whether or not its necessary?

 

I'm delving into dark waters here, all my experience is with toyota mr2's, so different kind of monster.

[WoodsWagon]

On VW transaxles, you can flip the diff to reverse the direction of travel because the pinion is meshed with the ring on the centerline of the axle. The ring and pinion are just bevel gears. On subarus, and most ring and pinion sets, the pinion is meshed offset of the centerline of the axle. You need special hypoid gears to be able to do that, and they only fit one way.

 

There is a guy making reverse cut ring and pinions for subaru AWD transmissions. You use an AWD transmission, use a splined coupler to make it FWD, grind out some casting ribs inside the front diff area of the case, put the reverse ring and pinion in with the diff flipped, use custom axle stubs to go to VAG CV cups, and build mounts for it. It's a lot of work, and spendy.

 

Here's the alternate solution: Use the portal axle gear reduction box's out of an early bus. It would take some fabrication to mate those to the IRS

rear control arms and use a CV axle instead of swing arms, but that gets you the reversal of direction, better ground clearance for the subaru oil pan, and gear reduction for bigger tires all in one.

 

For the front diff, use a subaru rear diff, flip it upside down, and install the cover right side up to keep the vent and fill plugs in the right spots. It's not perfect, and you will have to do some figuring on what ratio to run to match the transmission final + the bus portal boxes, and you can use different tire sizes front to rear to make up for small differences. Subaru diffs are available in 3.54, 3.7, 3.9, 4.11 and 4.44. Your 80's GL box is a 3.9 most likely.

Edited May 25, 2011 by WoodsWagon

[Eversor]

at that rate i might as well take the old vw bus awd drivetrain and use the whole thing. BUT they arnt easy to find so I'm definitely going to consider the options you played out here. Thanks for the advice.

[nova 1971]

Hey check this link might be just what your looking for. (wink wink)

http://www.bremarauto.com/products/subaru-2wd-conversion-kit/

[Eversor]

fine for a rail or buggy application but i kind of wanted to keep the 4wd Hi/lo for rock crawling, or just awd with good power behind it and low gears