Rob Roy

I know there is a thread on this somewhere here, but couldn't find it.

This is hypothetical at the moment - how easy is it to swap a manual transmission from an 1980 euro into an auto S4 (87-89)? A donor car would be available, with TT, axles, bellhousing, clutch, etc all available. Wrenching is not an issue.

Thanks,

rixter

don't swap the early manual into a later car, you're gonna want to go with an 85 up due to the syncro issues in the early cars...
that aside, it's a LOT of work!.. including a firewall section being swapped in IIRC

Jim bailey - 928 International

the dilemma will be the clutch and flywheel puzzle. You need the big trigger ring of the s-4 to run the electronics, the two disc clutch will not work on a late manual flywheel (if you had one) the bellhousing is larger for the 87> single disc clutch so any way you look at it you would need some additional rather $$ parts. The custom way is to use a 85-86 manual flywheel but with the trigger ring from an automatic S-4 pressed and welded to the 85-86 manual flywheel that allows you to use the early double disc clutch. You also have to ask how good are the driveline parts from a 25 year old car unless you have driven it.

Fabio421

On a related note. How much trouble is it to swap an 85 or newer 5 speed into an 84 w/ a 5 speed?

svp928

I did this swap , but my car is an 85, so I can't address the flywheel issue. The mechanical part of the swap is really just a bolt-in, with the exception of the mastercylinder mount. On my car, the was no hole or reinforcement in the firewall, so I had to add that myself, and it was the hardest part of the job. I had a ton of help the Mark and Jim at 928 Int'l- they kindly told me I was nuts, but helped me anyway....
They provided me an 83 euro close-ratio, 2.75 final, LSD transaxle freshly rebuilt, and all the ancillary parts to go with it. I have not had any synchro issues yet. I track this car, and drive it recreationally, and the this trans absolutely made a whole new car out of it- definitely worth it to me.
However, I agree with the advice regarding a later trans. I wanted the close ratios and the final drive , but couldn't find a late transaxle- so I'll live with the synchro issue when it comes up.
I recommend putting all new cylinders, pressure plate, discs, and lines in, as well as a rebuilt torque tube, and getting the transaxle rebuilt. This could get expensive- but you won't have to do it again for a long time if you do it right the first time....
You have to decide for yourself if its worth it or not- if you haven't spent a lot of money on the 87 already, and don't have any emotional attachment to it- its easier to sell it and find a 5-speed car. Some of us get foolishly attached to a particular car, and then you get go through this kind of
excercise.
So, mechanically, it isn't a hard swap to do, but could cost more than its worth.....

Vlocity

Ditto for SVP.

I did this with my 85. You will need to find a donor fire wall section to secure the Clutch Master mount. The biggest hurdle is positioning this mount in an area that you can not see and is nearly impossible to "feel". Jim helped me put together the parts list and I purchased a majority of the items I used from them. The best scenario for this would be to locate a 5 speed donor car and park it beside your project and then proceed at a leisurely pace. I decided to do this about 2 weeks before a track event, frantic would be the best term for the installation.

Very time intensive and very expensive if you are having to buy individual parts.

I've had my car for 10 years and do something to it every year. ( Last year I did a twinscrew intercooled install)

So if you are VERY mechanically inclined and don't plan on selling the car then go for it. If you are of average mechanical skills and can't see yourself still owning the car in 5 years then I would pass and trade.

Regards,

Ken