Go Back   986 Forum - The Community for Porsche Boxster & Cayman Owners > Porsche Boxster & Cayman Forums > Performance and Technical Chat

 
 
LinkBack Thread Tools Display Modes
Prev Previous Post   Next Post Next
Old 02-20-2008, 11:48 AM   #2
Registered User
 
Lil bastard's Avatar
 
Join Date: Feb 2008
Location: Du Monde
Posts: 2,199
It not a question of if you can machine the rotors, but whether you should. Porsche says you should not.

These rotors, because of their slots and holes require a greater thickness to maintain their overall strength than a solid rotor would. Cutting them down weakens them and makes them more likely to crack or shatter. Also, a rotor is basically a heat sink and the less material you have, the less efficient it is at absorbing and dissapating the heat energy from the system. It is exactly this heat, or more appropriately, energy transfer which stops the car.

On a warped rotor, the maximum allowable runout is 0.3mm (0.118"). And the max Peak to Valley roughness is 0.006mm (0.0002"). That means you don't get many passes to get it right and still maintain the required amount of material for strength and efficiency.

The other thing will be to find a shop willing to turn them on a lathe. This is not only because of worries about lessening their strength and making them prone to cracking and shattering, but also because the slots and holes really mess up the cutting bit on the lathe in a hurry. The shop will not make a profit replacing the cutting bits so quickly, unless they charge you quite a bit extra.

I wouldn't do it. Brake rotors are a consumable item just like the pads are. Gotta pay to play.
__________________
1990 Porsche 964 Carrera 4 Cabriolet
1976 BMW 2002
1990 BMW 325is
1999 Porsche Boxster
(gone, but not forgotten)
http://i933.photobucket.com/albums/a...smiley-003.gif

Never drive faster than your Guardian Angel can fly!
Lil bastard is offline   Reply With Quote
 



Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is On
Trackbacks are On
Pingbacks are On
Refbacks are On




All times are GMT -8. The time now is 02:34 AM.


Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2025, vBulletin Solutions, Inc.
Content Relevant URLs by vBSEO 3.6.0
Copyright 2025 Pelican Parts, LLC - Posts may be archived for display on the Pelican Parts Website -    DMCA Registered Agent Contact Page