erohslc wrote:
I still think there's a business case for custom 'on demand' bell housings based on
engine side, trans side, engine-trans distance:
1) Online application software lets you choose engine, trans from library of layouts, then engine-trans distance, performs cutting layout based on library of engine and trans layouts.
2) Laser/waterjet cut flat aluminum plates into pie segments and engine/trans adaptor rings.
3) Pie segments are multi-angle CNC bent into pyramid shapes.
4) Pyramid shapes are welded at single seam.
5) Pyramids shapes are welded to front/rear adaptor rings.
6) Surface prep (dress welds, sandblast, powder coat)
Voila! finished custom bell housing emerges.
Here's my DIY guide to fab'ing a bellhousing from scratch... 
Someone makes a modular bellhousing that hooks almost any American V8 and tranny together but I don't know if the do transaxles or Japanese engines.
Knurled wrote:
The ones to get from Audi would be the 016 FWD trans. This would be in the 5000 Turbo FWDs. The Boxster has an 01E which is the updated version of the 016 and is probably going to be a lot easier to find since most front drive 5000s were auto and *all* quattros were manual trans. I *think* Coupe GTs have 013s, not 016s.
I don't remember the trans code for the FWD trans used in the A4 but it is either 01A-related or it is based on the old 5spd from the front drive 4000s. I know of someone making VQ35-like power from a turbo four and he can break the old 5-speeds at will by rolling into the boost in a certain gear. Not good. If 01A-based, it should be "stronger" but at least it should be easy to take it out and put an 01E in if it proves to be too fragile.
IIRC there are no diffs available for any of the Audi transaxles unless you get one for a 944 Turbo and make it fit, or spend $1500-2000 or so from some company in Italy. 944 transmissions do not have a clutch friendly input shaft, however, so you can't just use that. I'm unaware if any Boxsters had good diffs right from Porsche or what is available.
So, you'll end up spending almost as much as you'd spend for a Porsche trans, and you won't have nearly the strength. Or rebuildablity.
O2J (weak 5 speed) or O2M (strong 6 speed)?
