Slave Cylinder Spacing from Clutch Fingers

I recently bought a SPEC stage 1 clutch kit SC091-8 for my 944 with an 5.3 LM7 swap. I know this is being posted in the LS1 section but my questions are not engine specific as far as I am aware.

The kit came with a 1/8" slave cylinder spacer and my question is relating to the throwout bearing surface/clutch finger spacing. As I understand, I should have about 1/8" of free space between the throwout bearing surface at the fully seated position and the clutch fingers when the driveline and clutch are all bolted up. If the measurement is less than 0.0" then the throwout bearing will permanently be applying pressure to the clutch fingers resulting in premature clutch wear. In my case these surfaces interfere by 1/8". In other words, I have a measurement of negative 1/8".

I followed this procedure to obtain these measurements:
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The provided 1/8" slave spacer is useless because I need to move my slave cylinder farther away from the clutch fingers, not bring it closer.

What can I do in this situation? Is there something that I am wrong about or misunderstanding? How can I go about ensuring my clutch/driveline is installed properly?

my stage 1 clutch from TPC went perfectly for alignment and such with throwout bearing with no spacer at all. but the difference most likely being that i have the old 2 piece bellhousing.

from what i recall the newer 1 piece bellhousing which is all people can get a hold of these days since GM doesn't make the 2 piece anymore requires a shim modification to make enough room for the clearance required on the throwout bearing for the clutch operation.

but your original build before the clutch upgrade would have required this on the 1 piece bellhousing in the first place, so i very much doubt my rambling helped.... so not sure...

"What can I do in this situation? Is there something that I am wrong about or misunderstanding? How can I go about ensuring my clutch/driveline is installed properly?"

ndog52,

In my build I used a 5.7 LS1 with the Corvette bell housing, SPEC clutch/PP, and GM throwout bearing provided by TPC.  I'm not an expert in GM small blocks so I can't speak to the backend differences between a 5.3 vs a 5.7.  

However, I spent a good deal of time checking all my clearances and documented the adventure in my project thread. The link below will take you right to it.  If you haven't resolved your situation already, perhaps it will be helpful.

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Good luck!!

Gutterboy wrote:but your original build before the clutch upgrade

Raymond-P wrote:However, I spent a good deal of time checking all my clearances and documented the adventure in my project thread.

Thanks a lot for your input guys! I read your replies a few weeks ago and heeded your advice. Sorry I didn't get back sooner, but you both helped me solve the problem after spending some time doing a little math and reading through Ray's post.

FYI, my car is not an existing LS swap, I'm currently building it for the first time. I have a two piece bell housing and I'm using a bunch of used TPC swap parts that I bought as a package deal from someone who crashed their swapped 944. These parts are used and some of them are of unknown origin. Ie, the slave cylinder.

I ended up deciding to replace the used slave cylinder with a new stock unit just for peace of mind and the new unit actually changed my measurements slightly. Long story short, I now have 0.197" of space between the fully seated throwout bearing surface and the clutch fingers. Good to go . Fast forward to today, I now have the engine installed and the slave bled and working well.
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Ray, your build thread has been absolutely instrumental in my 5.3 swap build. I can't tell you enough how great it is to have such an excellent resource available for free. I'm a huge fan of your recent table of contents upgrade too. Cheers. And congrats on your first startup.

After about two years with the 944 under the knife, I should have this build on the road by Spring!

ndog52 wrote:

Gutterboy wrote:but your original build before the clutch upgrade

Raymond-P wrote:However, I spent a good deal of time checking all my clearances and documented the adventure in my project thread.

Thanks a lot for your input guys! I read your replies a few weeks ago and heeded your advice. Sorry I didn't get back sooner, but you both helped me solve the problem after spending some time doing a little math and reading through Ray's post.

FYI, my car is not an existing LS swap, I'm currently building it for the first time. I have a two piece bell housing and I'm using a bunch of used TPC swap parts that I bought as a package deal from someone who crashed their swapped 944. These parts are used and some of them are of unknown origin. Ie, the slave cylinder.

I ended up deciding to replace the used slave cylinder with a new stock unit just for peace of mind and the new unit actually changed my measurements slightly. Long story short, I now have 0.197" of space between the fully seated throwout bearing surface and the clutch fingers. Good to go . Fast forward to today, I now have the engine installed and the slave bled and working well.
[You must be registered and logged in to see this image.]

Ray, your build thread has been absolutely instrumental in my 5.3 swap build. I can't tell you enough how great it is to have such an excellent resource available for free. I'm a huge fan of your recent table of contents upgrade too. Cheers. And congrats on your first startup.

After about two years with the 944 under the knife, I should have this build on the road by Spring!

Hello Mr. NDog. Would you mind sharing the exact throwout bearing you purchased? I have the same problem where my T.O. bearing is too tall causing it to press against the pressure plate fins when it is fully collapsed. I apprecaite the assistance and please say hello to Ogopogo for me!