Board logo

Audi 01E stressed member
coyoteboy - 24/10/17 at 12:22 PM

Is anyone, that anyone knows of, running an Audi 01E transmission as a stressed, or semi-stressed member?


nick205 - 24/10/17 at 03:13 PM

A quick Google shows some cars with it as a stressed member. Looking at the housing itself though it doesn't have any obvious mounting points to do so.

What do you have in mind?


Agriv8 - 24/10/17 at 04:22 PM

I would have though it must be a semi stressed in its original use

2 mounts on engine 1 or 2 mounts on gearbox all work together while engine running.

Agriv8


Dpb511 - 24/10/17 at 04:25 PM

I have been looking at this myself, semi stressed is the better solution as I wouldn't want to risk the fatigue of the casing. I would want to be reinforcing it at a minimum if it's street used.

There are a few places I believe you can mount in the sides of the case and I'm entertaining the idea of a bellhousing adaptor plate with additional material either side of the box for additional fixity from the firewall and for forward suspension points

I need some detailed dimensions of the box before I can proceed with the design (ie pull finger out and buy one) and ensure it's safe enough


nick205 - 25/10/17 at 07:41 AM

quote:
Originally posted by Agriv8
I would have though it must be a semi stressed in its original use

2 mounts on engine 1 or 2 mounts on gearbox all work together while engine running.

Agriv8



True, thinking back to my Pinto it had 2x engine mounts (1 either side of the block) and 1x gearbox mount (underneath the tail). Works fine in tin tops, kits and locosts.


Ugg10 - 25/10/17 at 09:42 AM

Just for my own benefit -

In terms of fully stressed do you mean mounting the rear wishbones onto the block of the engine and then mounting the engine block to the chassis i.e. all loads form the suspension go through the engine bock to the chassis. This is my understanding of what a fully stressed engine means. This is often used in formula type cars to reduce rear end weight.

The alternative is to mount the engine on "out riggers" and the rear of the gearbox to the chassis and then mount the rear wishbones to the chassis as well. In this configuration suspension loads go to the chassis and the engine only sees road vibration loads through the mounts (minimised by rubber bobbins usually). An alternative as you have identified is to mount the engine/gearbox via a plate in between them removing the need for the outrigger type setup.

This guy is using a spacer type plate on the front of the engine to mount the engine in his Porsche 962 Le Mans car replica with a twin turbo LSX (maybe LS7) engine / Porsche gearbox build (not very locost !).

https://www.pistonheads.com/gassing/topic.asp?h=0&f=30&t=361836&i=1200

[Edited on 25/10/17 by Ugg10]


Dpb511 - 25/10/17 at 02:01 PM

Precisely, fully stressed member being there are no additional features to take loads besides the engine/gb assembly.

I wouldnt consider most standard cars a semi stressed member if they are not solidly mounted, as the only loads going through them are the reactions from the driveline and the chassis stiffness they add are negligible as the crossmembers will be doing most the work.

My aim is for what I would consider a 'semi' stressed member, where some chassis load is still taken through the engine and gearbox using a spacer/adaptor plate with outlying features (like you have shown) to additional members. The idea would be to reinforce them to prevent any fatigue that will induce cracking, or any flex that will cause issues with shaft alignment.

Ideally I want to run a sandwich plate on the sump of the engine that connects from the firewall to the adaptor plate and additional (removable) steel tubing connecting from this engine/GB adaptor plate to the firewall/rollbar.

I do have concerns about the symmetry of the gearbox to allow for rear suspension arm mounting - but the idea would be connect the front of the wishbones to the adaptor plate mounts, and the rear on an optimised U bracket with the existing fixing holes on the gearbox.


coyoteboy - 18/11/17 at 12:41 PM

Yes my initial concept was "semi stressed" (still stressed, terminology aside) because I can't see a decent way of making a fully stressed configuration. The thing is, I'm not sure it's really worth it and I was looking for inspiration around the idea. The reason I am not sure if it's worth it is because if you're going to get any benefit from it you need to understand the scale of safe loading in order to minimise the members nearby. It would have to be rigid mounted, and I'm fine with that, but if you need to build a support truss and over design that, there may be better solutions that just hang the box.