Manuel928S4

Hello,

I have the opportunity to purchase a 86 manual trans car with a seized engine to do a manual swap on my auto 88 S4. I have been reading and can't find any confirmation that it can be done or if I need other parts.
Can I reuse my current shocks and springs and brake parts?
What other parts will I need to make this work correctly?

Thanks!!

James Bailey

It can be done.....only creative part is fitting a 87 up timing ring to the early style double disc clutch smaller fly wheel. It might also need the rear suspension cross member swapped too.

Mrmerlin

Ideally you will have a complete car to harvest parts from,
Also since your going to need a clutch you could just go buy a single disc clutch assembly and get a used clutch flywheel (87 on) from 928 intl half price sale, this so you can keep the S4 trigger ring. without having to retrofit a twin disc clutch assembly.and put on a S4 trigger ring
NOTE make sure you also get the 87 on clutch master cylinder and the slave cylinder.
the 86 slave is too short, both the body and the pushrod

and get a Greg Brow flex line for the slave cylinder.

As JB suggested check the PET for the relevant rear cross members part numbers'

James Bailey

You also need to fabricate move the small bit of firewall where the clutch master will mount from the early car to the S-4 .....rivets and glue will suffice as you mount it inside the car.

Petza914

The early manual transmissions aren't great, even when working as they should and this is a good bit of work. You'll like the end result much better if you look into and can afford the C5 Z06 transmission upgrade from 928 Motorsports. I'm very happy with mine.

hacker-pschorr

If it were me, I'd do the swap and use the later clutch assembly. If that double disc is in good shape you should be able to sell it for enough money to mostly fund buying a new or used single disc setup.

Well, not to drag another thread down with that discussion, it's a moot point here since the later style synchros went into effect in 1985.

Petza914

Wasn't aware of the internal differences between my 79 box and the 85 and newer ones. Thanks. I still like the ratios and having the extra gear better though. The ability to run 2,000 RPM at 85 MPH makes for easy high-speed cruising like I did just this morning on the way to the airport with the cruise set at 90, and actually working

Manuel928S4

Ok, thanks for all the responses, I guess I will be looking for the later style clutch and flywheel related parts. I will be updating when I begin the conversion.

I would really like a t56 trans, but right now its way out of my budget.

icsamerica

Porsche 5 speed is fine and it fits the nature of the 928. Save the t56 for a different car.

Frankly speaking there is way too much "buy this and that... from this vendor " on these forums, its like a constant beat of an infomercial. I really dont remember that 20 years ago when Rennlist was a daily email diggest. Times change.
*rant over*

I have a new T56 Magnum behind a V12 on a OT car. Driving both the 928 5 speed and the OT T56 6 speed regularly makes me wish the throughs on the 928 were a bit shorter and the the T56 much longer. No car is perfect and I rarely drive them back to back as the pattern is different and I cant code switch that fast. On the T56 I'm more hesitant shifting from 5th to 4th quickly for fear that I might catch 2nd. It's happened to me... the synchros are so good it that it will do it. I never worry about going from 4th to 1st instead of 3rd, on the 928, because of the distance and deliberate movement involved. On the 928 I love that 1st and Revere are back to back, This makes parking lot / gas station and other close quarter maneuvering more natural too.

That said the Later revised 928 5 speed shifts great for a much older design and the longer movement of the shifter coupled with the long movements of the clutch feels more natural and synchronized... like the car is a extension of your body. By comparison the OT T56 car has the same longish clutch movement but a far shorter shift movement and it feels, out of time, un-synchronized, less natural and disconnected when compared to a 928.

As with most things these days the T56 was designed on a computer and less so in the real world. It technically better by every metric and designed so a single unit can fit multiple applications. The 928 5 speed, on the other hand, was designed when more development work was done in the car by a person, in real world conditions and it only has 1 application. It's more the engineers personal vision of how stick work was to be done in this particular car at the time and I love that.