Slipping clutch

[J. Salmon]

I posted this on my build forum but it really applies more here. I have an LS7 with the Ricardo and all stock accessories (clutch, slave, shifter) bolted to the SLC flywheel (admittedly 5 years old). The clutch started slipping. There are hot spots on the flywheel but all is tight and dry.

Anyone else have clutch issues? Anything I should look at?

Thanks!

-J.

 

[Fran Hall RCR]

An SLC customer had a similar issue a while ago...we got the flywheel back and recut the face and made a slight modification to the flywheel at the same time.
The AP/Stillen clutches (we have in stock btw) we use have a slightly different tolerance and the mod. we made takes this into account for future clutch changes.
Send it back and we will do the same to yours...

 

[Alex]

Just for clarification, the cause is using a Ford OEM clutch setup with the 'unmodified' LS flywheel; using the Stillen clutch package with the 'unmodified' flywheel would be fine though, correct? (unmodified meaning a flywheel that was sold 3-5yrs ago)

 

[Fran Hall RCR]

Not necessarily Alex...I had a OEM in my personal car that had an LS7/Ricardo and never slipped under normal hard usage track/street...

We made a change on the flywheel we make to accommodate both type of clutch by stepping down the surface past the friction surface...the issue is that the rivets used on the clutch friction plate have varied over time and once there is some wear on the plate the rivets may contact the flywheel creating hotspots and slippage.
We will happily make the modifications to any existing customers flywheel free of charge (cust. must pay shipping etc though)..this will mean trouble free driving in the future regardless of whatever generation/brand of clutch is used

 

[Grant S]

Fran how does one know which flywheel one has, if the upgrade has been done or not?
any telltale signs ?
Cheers,

 

[Fran Hall RCR]

The friction surface will have a slight step in it, then a radius to the center bolt circle

 

[Ken Roberts]

I think mine might be the newer style. Here is a picture of it.....

 

[J. Salmon]

That's not the same as mine was, but they I was almost a beta site tester
Anyway, my new clutch and flywheel is on the way, it was interference between clutch rivets and the flywheel. Most likely newer guys are fine, but it's worth taking a look just to be 100% before you bolt it up to save trouble.

I decided to upgrade to the AP clutch because I am a badazz and I deserve it.

Or maybe I am lazy and don't want to go back to it...

 

[Mesa]

I had both the stock and the AP/Stillen clutch, never noticed the stock set up having the rivet problem but, that does not mean I was looking all that close at the time. The AP obviously had flywheel to clutch disk rivet contact which actually held the friction plate up off the flywheel in a static examination., I of course had the non stepped flywheel and just had a local machine shop make the needed modification, which included making accommodation for the stock Ford throwout bearing.