I don't know what did mine in. Maybe because the rubber is 27 years old. Maybe because I doubled the HP. But the trans is low and I can easily move the transaxle with my hand. Anyone have any experience using solid rear mounts?

* Borrowed PICS from Mike Simard

 

Read up on this and its a big NO to mix front and rear mounts with solid/rubber. Can anyone tell me why? The 944 guys install just solid rear mount and they claim it improves shifting & handling.

 

I put some on my euro s this spring. They work great!

 

So if the transmission is locked to chassis, trans locked to engine with solid torque tube.
Engine still flexes.
What takes up the flexing?

And how does a very little movement transmission improve handling?
Just wondering.

 

I can tell you why.

We advertise the solid transaxle mounts ONLY to be installed on cars with full roll cages. Not roll bars - roll cages.

The 928, being a uni-body car, has a fair amount of twist and flex in the chassis. There are many, many proofs of this.

Lock the transaxle down to a twisting chassis and the next thing that will crack will be expensive.
Dont do it.

We have had good success with solid motor mounts on non-cage equipped cars, as the transaxle mounts have enough give to allow the engine to twist with the frame without damage. I have quite a few customers like this out there and several years on my own 91 GT that I am confident saying this.

However, to take out that last elastic - the rubber transaxle mounts - is to commit that the frame will never twist again. Be sure about that.

And NEVER install solid transaxle mounts with rubber motor mounts. The engine winds up a bit when you drop the clutch hard, and the transaxle is meant to twist with the engine in unison.

SUMMARY:

Solid engine mounts with rubber trans mounts = OK
Solid transaxle mounts on a roll cage equipped (strengthened) car = OK
Solid transaxle mounts with rubber engine mounts - NEVER OK

 

I'm going to have to say I don't totally agree with carl on this 1! I think you can put in solid MM and Trans mounts w/out breaking the unibody. I think a car that has trashed trans mounts would be way harder on the unibody than a fixed tranaxle. keeping the rotation down on the drivetrain is always good. my rears tires would shake something fierce b4 I put in the solid transaxle mounts, and I hate wheel hop!

 

Thanks Carl!

 

You wont break the unibody. The unibody will be fine.

I did not enjoy replacing the cracked bell housing, however.

It happens all the time... I label something "competition only" and they still find their way on to street cars.
People are gonna do what they are gonna do. Its OK. I just want you to be aware of the possible complications.

 

Tony,

I really like the pic you have in your avatar. Thats a very professional install. Well done.

 

I'm with Carl on this one- the engine mounts need to take the twisting torque, not the transaxle mounts, and yes the unibody does twist- a lot! so solid on both ends without a full cage is asking to break the weakest link in the drivetrain assy- Carl says he broke a bellhousing, so I'd take his word for it.