[DeTomaso] CLUTCH BASICS / Dick Ruzzin

[Ken Green]

Reading a bit more in Tom Monroe's book, there is a table on page 71 with torque capacity vs pressure plate load in pounds, with curves for several disk diameters.  It looks like 2000 pounds is good for over 400 ft pounds.
 
But, Monroe also says that the centrifugal assist can more than double the force on the pressure plate in a Borg and Beck or Long pressure plate.  I don't think there is room inside the ZF bell housing for the weights which create the centrifugal assist, so just because someone with a Mustang can handle 500 ft-pounds thanks to the centrifugal assist doesn't mean a similar clutch clutch (minus the weights) can handle the same torque in a Pantera.
 
I don't recall that diaphragm pressure plates having a centrifugal assist, except for the weights on the inside ends of the fingers of the Centerforce pressure plate.  So, in general, diaphragm pressure plates maybe better suited for lower RPM engines making torque at lower RPM, and Borg and Beck or Long pressure plates better for high RPM, specifically drag race motors?  I don't recall most clutch manufactures getting into RPM range, but it seems like that is a major issue in pressure plate selection.
 
The worst case would seem to be supercharged engines making big torque at low to moderate RPM.  These probably require a twin disk clutch.  Maybe with a diaphragm pressure plate that doesn't rely on the centrifugal assist.
 
Ken

--- On Sat, 11/29/08, Göran Malmberg <hemipanter at hemipanter.se> wrote:

From: Göran Malmberg <hemipanter at hemipanter.se>
Subject: Re: [DeTomaso]  CLUTCH BASICS / Dick Ruzzin
To: Dickruzzindesign at aol.com, dyogi at hawaii.rr.com, detomaso at realbig.com
Date: Saturday, November 29, 2008, 8:56 AM

That was what I had in mind to do. But many clutch manufacturers does not
provide 
the nesesary numbers to do any calculations, they use some more public friendly
words like "suitable for smallblock with cams, headers, carbs and some
occational
track use". 
I was figuring to use some average coefficient of friction numbers for those
disc 
material in use in relation to diameter and static pressure numbers for a rough
calculation. 
A simple formula that everyone could use. Do you think that would be something?
Goran
  ----- Original Message ----- 
  From: Dickruzzindesign at aol.com 
  To: hemipanter at hemipanter.se ; Dickruzzindesign at aol.com ; dyogi at hawaii.rr.com
; detomaso at realbig.com 
  Sent: Saturday, November 29, 2008 5:27 PM
  Subject: Re: [DeTomaso]  CLUTCH BASICS / Dick Ruzzin


  It would be good if someone who knows, would give us all some basic criteria
on how to choose a clutch disc / pressure plate and maybe flywheel.



  All the best,
  Dick Ruzzin
  ____________________________________________________
  dickruzzinDESIGN at aol.com
  920 Whittier Rd. Grosse Pointe Park, MI 48230
  Phone: +313-824-0539 / Cell: +313-300-9558



  **************
  Life should be easier. So should your homepage. Try the NEW AOL.com.
(http://www.aol.com/?optin=new-dp&icid=aolcom40vanity&ncid=emlcntaolcom00000002)

_______________________________________________

Detomaso Forum Managed by POCA

Archive Search Engine Now Available at http://www.realbig.com/detomaso/

DeTomaso mailing list
DeTomaso at list.realbig.com
http://list.realbig.com/mailman/listinfo/detomaso