installed a coupe engine mount assembly into my cab
 

Based on a thread from awhile back (relating to how to improve a cab's handling), it was recommended that I replace the factory cab rear engine mount w/ one from a coupe. The cab has a built in dampener, which allows the motor to twist. The coupe is a solid link between chasis and motor. The cab assembly is also 5lbs. heavier (I weighed them both). First snag, the rear engine mount assembly I had was designed for a single pulley, my cab had a dual pulley. After some creative engineering (I won't say how I got around it; let's just say it's a temp fix until I get a single pulley) I got that to work. Second snag, on my engine mount the bolts (that go through the mounts on the chasis) thread into the crossmember. The crossmember for the solid mount had no threads, so I had to go on a search for a pair of M12x1.50 nuts. Finally found some at Autozone.

First impression is nothing notable. This is a good thing as I was concerned that bumps would cause shakes and vibrations but it feels the same as before. I assume the main difference will be noticed on the track. Next step now will be a pair of solid motor mounts (the prior thread also indicated that to benefit from solid mounts, I would have to first switch over to a coupe mounting setup).

You're going the wrong direction....
In order of "stiffness", the order from softest to firmest is:
- coupe mounts
- cab mounts ( aka "clubsport" mounts....*same* part number !)
- solid mounts

Wil Ferch

You're confusing the rubber mounts (4 of them) with the actual engine mount assembly (the unit that bolts to the motor and the corresponding crossmember that mounts the motor to the rubber mounts). The coupe assembly mounts the crossmember directly to the motor via 4 bolts. The cab assembly has a round rubber dampener and a shock. I converted this assembly over, still retaining the firmer rubber cab mounts on the body.

Here's the link to the thread:

http://forums.pelicanparts.com/porsche-911-technical-forum/62165-how-do-solid-sport-motor-tranny-mounts-stiffen-up-chasis-rigidity.html

OK.

--Wil Ferch

I would think you are well on the road to a LOT of chassis flex, Colby. Do you have a roll bar, or any chassis stiffening in your cabriolet? Have you added a camber bar in the front? Triangulated? I am curious because my targa has the cab mount on the 3.2 also. No noticeable problems, though it does flex like the average 30 year old targa...;-)