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The Ultimate CTS-v Brake Thread

155K views 955 replies 112 participants last post by  GGGGOAT 
#1 · (Edited)
*Update*
Later posts outline the V2 kit and V1/2 rear brakes.

This will be a little step by step guild to CTS-V1 brakes on a GTO. They will seem some track-day abuse and I will give my honest unbiased opinion on them.

I picked up the calipers from my local GM dealer. $360 out the door including the shim/pin kits.

First impressions; they are massive.


On a GTO the caliper mounts 180degrees off from the CTS-v location. This puts the bleeders pointing down so you have to move them to the top of the caliper. To do this you need to remove the crossover tubes and bleeders from both calipers then swap them over. They are covered in powdercoat so you will have to scrap the coating off the flare connections to get a wrench on them. The tubes are powdercoated to the body of the caliper so you will have to snap this off; this will leave an uncoated part of the caliper visible.

Brackets came in today; I sandblasted them and painted them with high-temp enamel.


Here is the cutting required on the caliper.


I'm using a big ass dremel bit in a drill to clearance the caliper. I taped up the pistons to keep metal shavings out.


HP+ pads.


Fastenal run for hardware. 12.9 grade 12mm 1.75 x 35mm and Nordlock washers.
 
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#44 ·
Page one updated.
 
#45 ·
I think I'm going to tap the OEM GTO hub to except the bmw holding screw. Having the rotor flopping around makes installing the wheels kind of sucky.
 
#49 ·
Petal is firmer.

HP+ pads screech like a MOFO.

ABS is kicking in anytime I get near the petal. Really blows; going to see if more bleeding fixes it.

Seems to have nice bite tho.
 
#51 ·
Bite wise they are epic. With HP+ pads more then 20% pedal gets ABS to engage; I pulled the ABS fuse and any time I got into the brakes at all they locked up.

I might have to go to a less aggressive pad, or maybe a smaller master to get some good modular feel.
 
#54 ·
Based on what you're describing and the modifications made (Larger rotor >greater torque arm leverage = less pedal effort. larger caliper >increased piston area, greater clamping force = less pedal effort) it sounds like a larger master is in order.

A bigger master cylinder would create less pressure, and therefore require higher pedal effort making the system easier to modulate… of course I have no clue what the ABS system would make of all those changes. This is why BBK manufactures keep piston surface area near stock or reduce it in the case of adding larger rotors; that keeps pedal effort, travel and balance near stock levels without the need to monkey around with master cylinders…

But the band aid solution is as you suggested, less aggressive pads; though that doesn’t cure pedal feel or travel.
 
#52 ·
You get used to the power; and less pedal throw.

Now to try them out on the track.
 
#53 ·
Wheel spacers hold up and my wheels never fell off at 100+ mph and torque stayed even. Plus 8000+HP cars runs spacers don't even know they are there.
 
#56 · (Edited)
Has anyone checked into the Buick Regal GS Brembo brakes working on our cars. This vehicle was produced as the Holden Vauxhall in AU. Might be another Brembo option. Maybe a direct bolt on since its also a Holden.
Come again? lol

I think you mean the Insignia.
http://en.wikipedia.org/wiki/Opel_Insignia

The Brembo calipers on that car are smaller than the CTS-V system. Not really a benefit.

EDIT: Second look says they might be very close to the CTS-V caliper. Wouldn't know without a comparison. Still more expensive than V-calipers.
 
#57 ·
Above 100 they have a shimmy under braking; going to pull them apart and clean the hubs even more.
 
#60 ·
More brakes then the tires can handle.
 
#61 ·
One rotor has too much runout; going to have to have it cut.
 
#63 ·
Some other considerations

I've got a few HPDE's on my CTS-v (fronts only w/ 645 rotors and EBC Blues) setup. Here are a few thoughts...

The pedal is waaay higher and really jacks w/ any heel-toe. If you have stock pedals, you know how challenging it is already...

I'm running BFG R1's and when warm are just enough tire for this combo. Street tires made for interesting brake zones.

I know everyone has an opinion on pads, but I really like this setup w/ the Blues. Don't be afraid to go that route.

Thanks to everyone here for experimenting and posting. I love tracking my Aussy Tank!



 
#66 ·
Brand new stoptech rotor had .070 runout. Had to turn it as I'm racing tomorrow.

 
#71 ·
Procut...the only way to cut a rotor
 
#72 ·
Local Firestone has all the cool toys.
 
#73 ·
That is a $9k to $10k brake lathe and is the only way you can ensure zero runout. It even takes into account hub assembly wear.
 
#74 ·
Dang maing, that suxxorz. New rotors have wobbly runout. DBA "swears" non of their rotors require turning before installation.

Looking forward to seeing the "ultimate cts-v setup." Man, I need to go to Heintz . . . maybe I'll get a tune as a xmas present, haha.
 
#75 ·
I love DBA but they didn't make a BMW 745i rotor.
 
#76 ·
Going to get a BMW rotor retaining screw and drill/tap my hubs.
 
#81 ·
I have an 06 and want to get it on the track. Where are you racing around here? Thanks
I'm the timing chief for SCR Region SCCA. We do AutoXs all around the Columbia area. The nearest real track is Carolina Motorsports Park north of Columbia; we normally do one time trial/pdx/club trial a year there.

Dec 8th is the Subaru Showdown; they have a $130 PDX including instructor for a ton of a seat time on a track.
 
#80 · (Edited)
I drove Mikers car a cople of days ago and basically 50 percent locks the front tires up.
And he's got 265s up front with a 180 tread wear.
The brake pedal feels better as well.
I will probably do something like this and send the calipers to a machine shop since the grinding is extensive.
 
#82 ·
They were great at the AutoX.

Tons better then stock.
 
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