SouthernSon

Trying to go big brake caliper on my C5Z but am out of state at this time. I really would appreciate it if someone has an 18" speedline or Alcoa wheel handy and can measure the inside diameter at the spoke hub.

Dirk Miller

When I've measured for big brakes, I was more concerned with the width of the fat new BK calipers where they could contact the inside of the spokes of my wheels. Per the company where my calipers came from, I was able to make a template. This was my only way of knowing if they really fit. Wishing you the best of luck.

SouthernSon

You are correct that it is a concern but I have spacer plates and extra long ARP studs on my SKF's. I have found that the 18" speedlines will work with the aero 6 brake calipers. Now if anyone knows whether or not I can mount the old SL6's to the rear knuckle I would be ecstatic.

sperkins

The spindles are the same front and rear so - yes, the SL6's will bolt up in the rear, but the piston sizes are wrong.

LF spindle is the same as RR
RF spindle is the same as LR

KNSBrakes

I put 18's on the FRONT w/ my Wilwood FSL6 kit.

Tight fit. W/ AL hat 2 piece rotors it worked - w/ one piece it hit. It's close though and even the different versions of the SL calipers may clear better.

SouthernSon

Using the aero 6 (race) calipers up front and the SL6's in rear worked pretty well on a C6 as I understand it from a local shop owner/SCCA competitor using OEM M/C. That is using 14" rotor up front.

Thanks for the info on the front to rear. I may try that and see if my C5 M/C can handle the volume okay. I may have to cut a hole in the floorboard.

OOps, update: I misunderstood the combo. I just learned that SL6's in the rear did not work well and changing to a larger M/C did require lots of force. Considering my big cam/less vacuum I may just go with front kit and live with oem on rear for time being. (everything is such a ^&* tradeoff).

Scooter70

You can get a little more brake torque in the rear by going to the 13" C6 Z51 caliper bracket/rotor. KNS posted that they're working on a Z51-sized version of their DBA 4K setup. I think that's going to be the best budget setup for the rear when keeping the stock calipers.

UstaB-GS549

Just went down in the basement.

17 1/2" at inside

16 1/4" at the mounting surface

SouthernSon

That will be close. The aero 6 race caliper requires a radius of 8.13". Will have to shim out to just barely clear rotor edge. I appreciate you checking that for me!