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[924RACR]

So we're going through having to replace the clutch kit in our NA racecar, after a failure of the pressure plate.

Searching online from the usual sources, the Sachs kit number was KF117-01 - pretty straightforward.

Found a great price on it from RockAuto, and it's arrived... and while the part # on the box was the KF117-01... the part # on the pressure plate is quite different, as is the pressure plate itself!

Porsche part # is 035 141 117 E

The KF117-01 kit is supposed to have the same part # for the pressure plate as came out of the car (with a snapped rivet): Sachs 3082 025 531

The new replacement is actually Sachs 3082 634 052

But dimensionally they're the same, despite being a very different design!

The new clutch disc is a bit different in design, but less dramatically so, and definitely seems to match in dimensions.

So they seem entirely interchangeable - and all the info I can find online points both pressure plates as being suitable for the 924, the Audi 100 and many other VW products.

So it seems OK... I'm gonna throw it in and see how it works... but anyone else have any exposure to/experience with?

Oh, and the new pressure plate is about 3.25# lighter...
_________________
Vaughan Scott
Webmeister
'79 924 #77 SCCA H Prod racecar
'82 931 Plat. Silver
#25 Hidari Firefly P2 sports prototype

[Raize]

Is there any way you could physically check the spring force / spring constant of the different pressure plates? I would be worried that the substitution is a weaker plate from a lower-powered car (due to the lighter weight) and may cause clutch slippage.

As an engineer it truly pisses me off that manufacturers are unwilling to provide information like this.

[924RACR]

I suppose that's one idea... though the old one was damaged, so I wouldn't trust a measurement of that.

Be that as it may... it's all back together and running now, and I can confirm that at least on stands it's fine, actuates and shifts properly. Next challenge will be the dyno, then the racetrack end of the month...
_________________
Vaughan Scott
Webmeister
'79 924 #77 SCCA H Prod racecar
'82 931 Plat. Silver
#25 Hidari Firefly P2 sports prototype

[Cedric]

Check the Sachs catalouge in the future, its great. It has pictures on the parts, and also the part number substitution history so you can see the whole chain of updates.

The replacement seems correct, and based on the pics in the catalogue they do look quite a bit different, but it has been like that for a long time, parts and their numbers changes over time, the best place to check that its actually right is their after market catalogue
_________________
1980 924 Turbo
www.instagram.com/garagecedric/

[924RACR]

That would be great... but the online catalogue sucks and doesn't even show that one. At least not in the US.
_________________
Vaughan Scott
Webmeister
'79 924 #77 SCCA H Prod racecar
'82 931 Plat. Silver
#25 Hidari Firefly P2 sports prototype

[Cedric]

[safe]