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YOUR RESEARCHC4s twin turbo drivetrain swap questions
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Use powersteering
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Turbo manual trans also uses powersteering to boost the slave clutch cylinder.
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So, I recently acquired an 03 C4s with blown engine. I am looking at all my options for repair. One option is a complete drivetrain swap from a 996 turbo car. I have searched for half an hour, and can't find specific details on the swap. Does anyone have details on the following:
Aside from complete engine, transmission, wiring harness, what else is needed from the turbo car to do the swap into a C4s?
Roughly, how many hours should it take a shop familiar with Porsches to do the swap if they have to pull all the parts from a salvage turbo car?
Any known issues without resolution for the swap?
There are a few other things you'd need. The turbo cars have the third radiator to provide extra cooling because of the heat generated by the turbocharged engine. You'd need to add that, plus remove the screen in your center radiator vent to allow airflow. Secondly, you wouldn't have the side air vents to direct air into the intercoolers. I'm not sure if this is an issue or not. Additionally, you'd have to modify your rear bumper vents for the turbo blow-off vents. Beyond these things, my biggest concern would be computer issues. I would presume that you could deal with this by installing the engine management system from the turbo along with the new engine. One more thing - make sure your new turbo engine includes the exhaust system. The turbo exhaust is totally different than the C4S.
It sounds like a fun, but expensive project. It might be worth comparing it to the cost of a normally aspirated engine with a supercharger added.
Thanks for the list Dennis. I would likely be looking at a whole salvage turbo car, so Ill check to make sure all those are included.
Do you have any idea how many hours the complete swap would take?
don't forget the instrument cluster as well. I'm not so sure the turbos have a center radiator. The c4s already has the side turbo radiators which are larger and thicker than the c2 radiators.
maybe the PSM/steering wheel sensor is different as well.
It would be easier to install the GT3 motor and transmission being that you don't have to deal with all the turbo stuff. I'd imagine they would have to move almost everything from the salvage Turbo car to the C4S tub with exception to the most of the interior. Engine/Turbo/Inter-coolers weight is not the same and the Turbo has different suspension to compensate for it.
My WAG is you'll wait a long time to hear from someone who's done the Turbo engine/drivetrain swap to a C4S cause it is while not impossible a really bad swap.
Good luck swapping the intercooler openings from the Turbo to the C4S. Those are part of the rear fenders and those are part of the body/tub. They do not unbolt like the front fenders.
My advice is to give up the Turbo engine/drivetrain swap to the C4S.
Your best option for repair is to source a 996 engine from a similar MY car and install it into your C4S. The swap is plug and play.
I concur totally.
Not to mention the fact that once completed you'll constantly have crazy little conversion complications driving you nuts.
I don't even consider engine conversions with these cars. Been there, done that. Never again.
