Based on what I see, you have a compound angle like I had. With my Boxster tranny my axle stubbs would "walk" out after 150 miles. The car would have no forward or reverse motion until the stub was hammered back into the tranny.

The stubs are held in with a $1 circlip (Porsche Dealer). They did not have enough tension to hold back against the tug from the suspension movement. You can try an O ring, thin one under the circlip.

In my case I realigned the the drivertrain to shift everything forward until it aligned straight but remained lowered. No more problems.

Not sure which Boxster tranny you have or if your stubs are held in the same. Unbolt the CV and see if there is a big bolt head under it. If not, yours are held in by the same circlip.

I have the 5 speed Boxster trans.

He had the custom axles and parts made at driveshaftshop.com

Drive it a few hundred miles and check to see if the stub is working its way out.

In looking at how high the transaxle already sits in the bracket, it appears that it may not be possible to section it. You'll need to take the stock upper washer plates into consideration too - (I think they're approx 1/2" thick). If those rubber mounts crack and fail and you don't have those plates in place, your transaxle could fall.

I'm also wondering if a different rubber mount could be fabricated, and located UNDER the 'flat bars' (instead of above)? ... looks like you could gain an inch or so there

If you're planning on raising the rear suspension (as you mentioned earlier) with taller springs, you'll gain even more equality between the center-line of the trans output shafts and the center-line at the wheel hubs. That should straighten out the axle angles enough to cause a lot less wear & tear on the CVs.

Not sure how heavy of springs are in there, but wonder how heavy I need for the LS3 engine, 180lb?
Sounds like 180lb are shorter than stock?
https://forums.pelicanparts.com/porsche-914...ed-details.html

I have the mounting plates on top now.

I'm not sure how I could move the trans forward any?

I would be worried about the cantilevered nature of that bracket. Hanging out on the end of that flat bar is a recipe for metal fatigue and eventual failure. It is absorbing all of the torque of the engine in one direction, then the engine braking in the other direction, and the load of the rear of the tranny bouncing up and down. Eventually they are going to break due to metal fatigue. I spent a lot of time discussing this very subject with Aaron (my machinist at Zims). We ended up making a mount that wraps around the back of the transmission and triangulates with two side mount points.

Here's a picture of my 914 with a Cayman 6 speed G86-21 trans.





You can see how it was built to prevent the flex in the mount. And I am less that 1/2 from the chassis transmission crossmember.

Just my $.02.

Wow, well thought-out design, Clay.

enjoyed your pics. thanks.