Brake hat offset and rotor thickness?
Team Owner
Joined: Jul 1999
Posts: 65,492
Likes: 230
From: Orange Park Florida
I dunno the exact specs but the mounting flange of the front/rear rotors is of two differant thicknesses....about 1/4 inch thick for the front, and maybe 3/16 thick for the rear....that makes them NOT INTERCHANGEABLE, as the offsets are too great for the calipers being fixed in postioin....they are same size otherwise ......
methinks someone specd a rong size hub back when, and whole bunch were delivered, and so it was just plainly cheeper to order another size rotor to cover the error, assign another part number and have done with it......
methinks someone specd a rong size hub back when, and whole bunch were delivered, and so it was just plainly cheeper to order another size rotor to cover the error, assign another part number and have done with it......
Drifting
Joined: Oct 2003
Posts: 1,426
Likes: 1
From: VetteMOD
St. Jude Donor '05-'07
Nick, I sense a conversion project going on. If you are looking for some big rotors that will interchange with C3 rotors, look at Mercedes rotors from a 2000-up CL500. They are 330mm dia., 32mm thick (C3=32mm), 76mm offset (C3 78.6mm). They would have to be redrilled for the GM bolt circle but should fit. Brembo PN BR25578
The offset measurement (76mm & 78.6mm) is from the back of the rotor to the hat face. This is the more "normal" method of measuring offset.
The offset measurement (76mm & 78.6mm) is from the back of the rotor to the hat face. This is the more "normal" method of measuring offset.
Thread Starter
Safety Car
Joined: Jan 2001
Posts: 3,637
Likes: 27
From: Norwalk Ct
yup, thinking of some nice 13" rotors (drilled/slotted) up front over the winter.
Had some good input from Kieth at Corvette Engineering, just wanted to get all the "right" info first.
Nick
Had some good input from Kieth at Corvette Engineering, just wanted to get all the "right" info first.
Nick
Melting Slicks
Joined: May 2001
Posts: 2,812
Likes: 4
From: Gig Harbor Wa
Originally Posted by lvrpool32
just wanted to get all the "right" info first.
What are you going to use for rotors and calipers?
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Thread Starter
Safety Car
Joined: Jan 2001
Posts: 3,637
Likes: 27
From: Norwalk Ct
Hi Howard,
do you happen to know what hat it is from Wilwood?? I have been on their website and seem to be going in circles.
I have already spoken to coleman, they can get me what ever I need.....
Nick
do you happen to know what hat it is from Wilwood?? I have been on their website and seem to be going in circles.
I have already spoken to coleman, they can get me what ever I need.....
Nick
Thread Starter
Safety Car
Joined: Jan 2001
Posts: 3,637
Likes: 27
From: Norwalk Ct
OK, what i have found.
Coleman sell an aluminum hat 1-7/8 offset (1.875) which is 0.029" more than stock. They sell a cast and a billet version and can drill them for 5 x 4.75 stud pattern
Wilwood sell a hat that is 1.88 offset (which is 0.034" more than stock) This comes 5 x 4.75" but the face is .25" which is thinner than stock.
Nick
Coleman sell an aluminum hat 1-7/8 offset (1.875) which is 0.029" more than stock. They sell a cast and a billet version and can drill them for 5 x 4.75 stud pattern
Wilwood sell a hat that is 1.88 offset (which is 0.034" more than stock) This comes 5 x 4.75" but the face is .25" which is thinner than stock.
Nick
Race Director
Joined: Nov 2000
Posts: 11,872
Likes: 12
From: Waterloo ontario Canada
The problem with hats and large rotors is the hats are small. Something like 7 to 8 inches in diameter and when coupled with a 13 or 14 inch rotor they look funny.
You really need a big 10 inch hat and I don't know who makes them this size.
You really need a big 10 inch hat and I don't know who makes them this size.
