Clutch slipping, or diff opening up in corners?
 

I'm having some issues with what I believe to be clutch slippage. However, in past experience, once the clutch had started to slip, it then went south rather quickly. In this instance, the clutch would slip when feeding power in the corners. The clutch never completely failed; even after a 3 day race weekend.

One friend thought it might be the diff clutches opening up... I believe that I have an OEM Torsen diff. These don't slip; do they?

2004 msm. ACT cover and race disc.

How stiff/what mods do you have done to the rear suspension? Another possible scenario is it is too stiff causing power oversteer.

I can't imagine why a clutch would slip only on corners.

<p>OEM diff won't slip.</p>

Lifting inside rear wheel? The OEM torsen will act as an open diff if one of the wheels has no traction at all.

wut

"However, if one set of wheels loses traction completely, the Torsen differential will be unable to supply any torque to the other set of wheels. The bias ratio determines how much torque can be transferred, and five times zero is zero."

How Stuff Works

msm has a TF, not a torsen
I too thought it had a torsen for a while, but no

sorry, missed the part that it was an msm

^ Tochigi-Fuji is what I was thinking.
Don't those sometimes fail?

Yes, and also I think they can slip. I'm trying to remember where I read that, I'll post up if I remember

<p>A lot of 03 TF were set up incorrectly at the factory. Also we just said that the MSM has a TF but I think thats wrong. Its the same diff as the S2000 which has a torsen. I think the TF was in the 03 and up regualar Miatas. The MSM followed the trend of getting rid of extra old Miata parts.</p>

<p>Which LSD in an MSM [Archive] - MX-5 Miata Forum</p><p>http://forum.miata.net/vb/showthread.php?t=508115</p><p>http://www.s2ki.com/s2000/topic/7755...-differential/</p><p>&nbsp;</p>

What clutch and how much power are you running? We killed an FM1 pretty easily on a nearly stock MSM setup (with MS and bigger injectors).

but how would a clutch slip only in corners? that makes no sense

Hard to tell from video, but this seems most likely. Looks like the car was bouncing when it slipped in the vid, and it was turning too, so this at least seems plausible. Clutch slipping is possible too, but seems less likely.

MSM has a bosch made gear type diff IIRC. Different from the Gleason made torsen in the rest of the cars, but the same type of diff. Its the unweighted inside rear spinning. Disconnect the rear sway bar and this will stop.

I can't speak for the msm diff but I know a factory 99 torsen can begin to slip with age. We've had a few go on some of our spec race cars, with only 130whp. They work fine except for really high load "aggressive" corners.

<p>Theoretically thats impossible, since there is no wear components in a Torsen diff. And I don't see how even a wear in the gears could cause &quot;slip&quot;.</p><p></p>

Oh yeah, sway bar. Get rid of that.

Torsens can wear out, but not in a way that will cause slip. There is some hardened washer that help keep pressure on everything that can wear down. Sadly there doesn't seem to be a source for replacement washers at this time.