Help Please 930 Hydraulic conversion

Does anyone know of what has to be done or bought in order to convert the trans side of the cable clutch system to hydraulic?
Any help would be greatly appreciated.

Thank you, Mike
Hi Mike,

I went down this route but as my set up is a little peculiar because I'm using an adapted Ford Bellhousing and large Ford clutch components rather than the smaller Porsche clutch, I don't have enough space to fit a hydraulic release bearing. As a result I will be adapting back to the mechanical release arm and slave cylinder set up, all be it a modified version. I did however purchase a low profile hydraulic clutch release bearing that fits a Porsche 930 box that I no longer require. It's a Tillton unit. All you need is one of these bearings and a hydraulic line to the slave cylinder. If you need photos of the bearing and or measurements of it, let me know.
Thank You, photos would be great. If it is not to much trouble , do you have a photo of the Slave Cylinder/ Arm set up you used. I have the stock arm here and a Wilwood cylinder. Just not sure how to modify/connect the two together.

Thanks so much, Mike
I'm yet to modify it, so I don't have a finished article yet. However, here are the photos of the arm and slave as it was originally. I'll dig out the bearing and snap some photos later on. Hope this helps.


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This is what I've done --just a bolt on and go arrangement, the slave ( common HJ 45 toyota) looks like over kill, but, seems to work OK --see working proto and potential production item


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Thank you guys so much, You guys made those? Very nice!!!
Martin, is your cylinder a push or pull. I ask because it looks like your set up moves the shaft clock wise (if it is a pusher) and Flatchats looks like his turns the shaft counter clockwise. Which is correct in shaft rotation? And is a hydraulic bearing necessary?

Thank you , Mike
I used a "Willwood" type circle track slave mounted on a fabricated bracket with a modified Porsche 915 release arm.


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I noticed that your guy's shafts are on the top. Mine is on the bottom, does that mean you guys had your differentials flipped? Or is my diff flipped?


Russ Noble

GT40s Supporter
Lifetime Supporter
Whelll ! ---- my model workths in any possssistion :laugh::lipsrsealed:

So Chris, do you flip your difference?? :laugh: :lipsrsealed:

Sorry Mike! Couldn't help it....

Seriously now, if you are using your 930 the other way up, (i.e original porsche way, not upside down), in a mid engined car eg GT40 and have 4 forward speeds and one reverse then your crown wheel has been swapped to the other side of the pinion. If you have 4 reverse and one forward then it has not!!

The normal GT40 type setup is to turn the trans upside down which gives the 4 forward, 1 reverse without having to swap the pinion and has the additional significant benefit of lowering the motor at the same time.
Thanks for all the help guys, no worries i love a good laugh. I only ask because i do not know enough about the porsche transaxles. I really dont know which way is up. I am building this car for a buddy. The chassis was a roller and all i have to do to it is convert the clutch and bleed the brakes. The rest of the car i have to build.


Terry Oxandale

Skinny Man
If the shifting mechanism is on top, it is inverted as in the photos shown thus far, and will work in our mid-engine configuration if no internal swapping has been preformed on crown wheel.


:idea: Aaah! -- very interesting, I'd like to follow your progress, as I'm helping a guy with parts for his Countach, Diablo and Reventon also a stretch limo style (can't remember which one)
Using LS1..motors to hopefully Porsche trans
Thanks Guys for all the help. Here's a link to some of the more recent work
Pictures by mbdiablovt - Photobucket

I must admit that i am using the Audi as a stop gap just to get my personal car moving. I really like the 930 4 speed. The one i am working on now has had the Diff flipped and rebuilt with every upgrade available.
You guys inverting your 930's, are you employing a spray bar for oil? Is that even necessary?

I'm running a 930 with flipped R&P and built a similar slave set-up, but I prefer yours. Have you created any more of them? Would love to acquire one.
One of the real benefits with flipping the transaxle is that you get a lower mounting position of the engine = better handling. You also get better angles on the driveshafts. So my advice is do not flip the crownwheel -flip the box. In my 915 box I have a gallon which gave a good oil level. I do not use a spray bar and it works fine for me however I have not raced on track in any longer period. I can also recommend SWEPCO 201 that is very good oil for these boxes.

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