M40 vs M42 clutch torque capicity

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Leo_328i
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Wed Nov 09, 2011 11:49 am

Hey guys,

I'm trying to find out some information regarding the difference between the M40 and M42 clutches in terms of their power/torque capicity.

I've done some research and found that the M42 clutches used in conjunction with the Downing Atlanta Supercharger kit have stood up really well with over 200ft pounds of torque which is great information.

My question is then related to using the M40 clutch and flywheel with a setup that has this sort of power - is the M40 clutch much worse in terms of power handling?

I cannot seem to find any information regarding this.

Cheers.
rix313
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Wed Nov 09, 2011 12:26 pm

I'm pretty sure it's the same unit.
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Leo_328i
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Thu Nov 10, 2011 8:45 am

The clutch kits are not interchangeable - the M40 single mass is a sprung hub clutch whilst M42 is not. Unless you are referring to just the pressure plate?
rix313
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Thu Nov 10, 2011 9:31 am

In that case, the single mass flywheels are the same, as are the gearboxes (getrag 240) so i don't see why you couldn't fit an M42 clutch as an 'upgrade'.
dsm2002
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Thu Nov 10, 2011 10:47 am

Leo

I am working through this at the moment with Jim Berry Race Clutches Brisbane. He is certain the the 215mm Saab turbo clutch cover is the same pattern as the m40/m42. Jim says the M40 and M42 clamp at about 1200lb, while the Saab turbo clutch cover is 1600lb or so. He often uses the Saab turbo clutch cover (Sach only!!!!) for other cars with turbos - it fits quite a few different cars. He can upgrade the pressure plate to well over 2000lb.

I hope to find out more tomorrow.

David
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Leo_328i
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Sat Nov 12, 2011 11:22 pm

David,

Let me know how you go! Which Saab clutch are you referring to?

Cheers.
dsm2002
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Wed Nov 23, 2011 4:16 pm

I have not been able to get further information. jim was not forthcoming with further information other than he can build a clutch kit for about $1000±. Too much for me.
rix313
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Wed Nov 23, 2011 4:42 pm

The stage one kits I sell are around £220GBP and are 20% upgrade.
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