Switched to 6-pot CTS-V brakes

[G8V8]

I replaced the 4-pot GXP calipers and rotors with '09-'11 CTS-V 6-pot calipers and Centric rotors. They really feel good even after going from GXP EBC Yellowstuff pads to ceramic pads for the 6-pot. Installation required drilling the hubs for the larger bolts but that was all the modifications required. My GXP SS lines worked fine and these fit inside the 19" VMR 701s with a bit of room to spare. The rear uses Camaro SS Brembos and blank HSV rotors, (no brackets required and the stock e-brake is retained). Sorry for the crappy cell-phone photos.

[thebeast]

Looks awesome. That's a mod I'd like to do when I have money and nothing to spend it on.

[cynic783]

Awesome but losing the E-brake is a bummer. How do you park it on a hill? Keep chocks in the trunk?

EDIT: Doh! I see you are automatic with "Park".

[G8V8]

Awesome but losing the E-brake is a bummer. How do you park it on a hill? Keep chocks in the trunk?

EDIT: Doh! I see you are automatic with "Park".

LOL, Read it again. It says the e-brake is retained. The HSV rear rotors use the same e-brake shoes as the G8.

[cynic783]

Reading comprehension fail.

So what you are saying I can use the Camaro 4-piston Brembos with the HSV rear rotors and retain E-brake functionality?

That is the northwest passage! There are some threads of folks not able to upgrade rear brakes and retain E-brake functionality I remember.

What is different about HSV rear rotor versus whatever the alternatives are?

And the Big Question: how much $$$?

[Eidolon]

Reading comprehension fail.

So what you are saying I can use the Camaro 4-piston Brembos with the HSV rear rotors and retain E-brake functionality?

That is the northwest passage! There are some threads of folks not able to upgrade rear brakes and retain E-brake functionality I remember.

What is different about HSV rear rotor versus whatever the alternatives are?

And the Big Question: how much $$$?

The trick is the HSV rotors, as you note, which are made for the Holdens in the Land Down Under. So they fit the stock e-brake shoes.

Most people, myself included, use a brake bracket created by Andy/realsquash that repositions the caliper itself so that Camaro rotors can be used. The upshot is easier availability of rotors, since the Camaro and 2009+ CTS-V use the same rear rotor. The downside is that the inner hub diameter of the Camaro rotors is larger than the G8. So then you either have to get special e-brake shoes or you have to completely replace the rear spindle with Camaro parts if you want to maintain the e-brake.

The downside of the HSV rotor setup is that the rotors are a little more expensive, though only by $100 if you look at MarylandSpeed (http://marylandspeed.com/dba-4000-series-rotors-hsvrear-camaro-caliper-conversion-20082009-pontiac-g8-42031-p-3404.html). They also take a little longer to get, since they're imported. Finally, you also have to shave the pads a bit to get them to fit. I think. That last one confuses me.

Oh, and congrats, OP, on the new calipers! Feel good, don't they? :)

[G8V8]

The HSV rear rotors that DBA can get for you are 350 mm diameter which makes them bigger than G8 but not as big as the Camaro SS rear rotors. These use the same e-brake as the G8. The Camaro SS and CTS-V rear Brembos bolt right to the hub with no custom brackets. The use different rear bolts than the G8 but no drilling is required.

BUT, you will need to trim about 1/8" off the edge of the rear pads because the pads hangs over the edge of the rotor by that amount. We just use a cutting wheel on a Dremmel to trim them. We have 4 G8s (2 GTs and 2 6M GXPs) running this set-up and it works great.

MD Speed used to be able to get the rotors but I think a shop in SC now does it. If you are interested, you can e-mail DBA USA and they can tell you the best distributor to use and they can tell you if they have any in stock or an ETA. I think they have a set or 2 of the T3 version.

[G8V8]

The trick is the HSV rotors, as you note, which are made for the Holdens in the Land Down Under. So they fit the stock e-brake shoes.

Most people, myself included, use a brake bracket created by Andy/realsquash that repositions the caliper itself so that Camaro rotors can be used. The upshot is easier availability of rotors, since the Camaro and 2009+ CTS-V use the same rear rotor. The downside is that the inner hub diameter of the Camaro rotors is larger than the G8. So then you either have to get special e-brake shoes or you have to completely replace the rear spindle with Camaro parts if you want to maintain the e-brake.

The downside of the HSV rotor setup is that the rotors are a little more expensive, though only by $100 if you look at MarylandSpeed (http://marylandspeed.com/dba-4000-series-rotors-hsvrear-camaro-caliper-conversion-20082009-pontiac-g8-42031-p-3404.html). They also take a little longer to get, since they're imported. Finally, you also have to shave the pads a bit to get them to fit. I think. That last one confuses me.

Oh, and congrats, OP, on the new calipers! Feel good, don't they? :)

They feel great.

You need to trim the rear pads when using the HSV rotors because the distance that the rear calipers are mount with this set-up is about a tenth of an inch further out from the hub center than idea. Because of this, the pads overhang the outside edge of the rotor a little. conversely, if the rotors were 352 mm or 353 mm in diameter instead of 350 mm, not triming of pads would be required either.

The HSV cars use these 350 mm rear rotors but a different brand of performance caliper that also fits our hubs but locates the pad a little further inboard.

DBA usually has a set or 2 in stock in the USA that are either the HSV style slots or T3 slots or XS (drilled and slotted). It varies with demand. If you want blanks (no slots or cross-drilling) it can take 30-45 days.

[Blue_Streak]

How do the Centric rotors feel? They running true out of the box?

[WhiteDeathLSX]

Nice! Love mine!

Sent from my DROID RAZR using Tapatalk 2

[G8V8]

How do the Centric rotors feel? They running true out of the box?

Rotors feel great. contrary to Centric's website, they are not co-cast and the weight they list is wrong. These are 28 pounds each. That makes them 3 pounds heavier than CTS-V co-cast and 1 pound heavier than 2-piece ZL1 / CTS-V rotors. However, for the money, they are a great buy.

[donkeyGT]

G8V8 LOVE the look..I don't even have my 4 pots done yet..can only wish for 6's..on a sidenote I had to get a Camaro rear rotor to finish my install $111.00 to my door from GMpartsdirect.

[Blue_Streak]

Rotors feel great. contrary to Centric's website, they are not co-cast and the weight they list is wrong. These are 28 pounds each. That makes them 3 pounds heavier than CTS-V co-cast and 1 pound heavier than 2-piece ZL1 / CTS-V rotors. However, for the money, they are a great buy.
We're better off imo, it sounds like the aluminum centers are causing problems on the cts.

[Eidolon]

We're better off imo, it sounds like the aluminum centers are causing problems on the cts.

So far, so good with mine. Is it the two-piece or one-piece co-cast that're having the problems, and what kind of problems?

[Blue_Streak]

Supposedly the centers are galling against the mounting face of the wheel and causing clicking noises? This is with the one piece rotors. Just what I've read, no first hand experience here.

[bonners]

Can any of my fellow US ve owners tell me if there is such a thing as an aftermarket replacement rotor for the 6 piston rotor. Ie is there like a dba slotted version

[G8V8]

Centric makes a nice, quality rotor for about $100 each. They are blank. Not sure if they will slot them.

[G8V8]

Here is a photo of the 4-pot pad and the 6-pot pad.

[joker2]

So let me get this right, if I have the Camaro SS rear rotors and CTS-V calipers I won't need the Squash bracket and I won't have to trim the pads to make them fit BUT I won't have the e-brake functionality as well?

[Eidolon]

Supposedly the centers are galling against the mounting face of the wheel and causing clicking noises? This is with the one piece rotors. Just what I've read, no first hand experience here.

May be a rare thing. Two track events on mine so far without issue.

Sent from my Galaxy Nexus using Tapatalk 4 Beta

[Eidolon]

So let me get this right, if I have the Camaro SS rear rotors and CTS-V calipers I won't need the Squash bracket and I won't have to trim the pads to make them fit BUT I won't have the e-brake functionality as well?

Not quite.

Camaro rear calipers and CTS-V rear calipers are the same physical caliper and both will work on our car. If you use the calipers from 2009+ CTS-V, you'll need to switch the bleeders and crossover tubes to orient the calipers properly. Not sure about the 04-07 CTS-V calipers. But the smallest piston in the caliper should always be the "first" piston the rotor spins into.

If you use the special DBA rotors imported from Australia, then you can keep the e-brake, but you'll need to trim the pads.

If you use the rear rotor from the Camaro or 2009+ CTS-V (they're the same rotor; and the 04-07 CTS-V rotor will not work on our car), then you'll need the Squash bracket and you'll lose the e-brake without the special shoes.

That about sums up your options for OEM-sourced or OEM-spec brake upgrades.

Sent from my Galaxy Nexus using Tapatalk 4 Beta

[drivecustoms]

Damn... This would have been nice to now a few months back. I just redid my brakes with all EBC slotted rotors, Bluestuff pads and Russell SS lines. I am happy with it but doing the Bembos would have been nice. I am a Brembo dealer but even at my discounts thier aftermarket Big Brake kits are out of my price range... HAHAHA

[skinsfangreg]

Supposedly the centers are galling against the mounting face of the wheel and causing clicking noises? This is with the one piece rotors. Just what I've read, no first hand experience here.

This is only an issue with the CTS-V wheels and rotors. Initially the GM TSB was to clean rotor & wheel mating surfaces. TSB was updated to replace rotors with 2pc ZL1 style. Newest TSB calls for replacing lug nuts with new style and changing torque specs. No clicking issues on G8's that I've heard of.
I've had my 6p V calipers and V rotors installed for around 16-18 months without issue. That's with me using 4 different sets of wheels in that 16 months.

[MAC the KNIFE]

question about the centric rotors you used. which part number? where did you by them? (could not easily find any of these on google or amazon)

from their site, for the cts-v2
1. Co-Cast, Front, # 120.62128, quantity 2
2. 2 piece Discs, Front Left, # 125.62134, quantity 1
3. 2 piece Discs, Front Right, # 125.62133, quantity 1

Thank You!

[G8V8]

I used the one called C0-cast. It is a one piece rotor and not the "co-cast" type like the original OEM rotor. It weighs a pound more than the 2-piece ZL-1 style rotor. Mine have performed great, especially for the money.

In their descriptions, when it says co-cast or 2-piece, it means they replace these OEM style rotors, not that the Centric rotors are co-cast or 2-piece. At least that is what it meant for the co-cast style.

[MAC the KNIFE]

i found part number 120.62128 on rockauto for $83.79. 370mm outer diameter.
the other 2 part numbers don't even show on rockauto.

[hayabusa160]

tirerack carrys them thats where i got my rotors. i got the cryo treated ones for a little bit more.

[MAC the KNIFE]

tirerack carrys them thats where i got my rotors. i got the cryo treated ones for a little bit more.
Cool man! Thank You. Centric's own website didn't even show CRYO treated ones. tirerack will save me about $90 per rotor

[G8V8]

I found an ebay seller ( http://www.ebay.com/itm/161087522812?ssPageName=STRK:MEWNX:IT&_trksid=p3984.m1497.l2649 ) with nearly new CTS-V OEM co-cast front rotor take-offs. They were asking $150 each plus $40 to ship 2. I offered $120 a rotor + shipping and they accepted. I got the rotors a few days later. Both were in ex shape. One still had the factory protective coating intact and the other had the coating barely worn off. I weighed them and they are 25.4 pounds each. That makes each rotor 2.8 pounds lighter than the Centric. I like the aluminum center hat section so I painted my rear HSV rotor hubs to match. There was nothing wrong with the centric rotors but for this price, I wanted the co-cast rotor's lighter weight and look. Here are some photos.

[I12XLR8]

Here is a photo of the 4-pot pad and the 6-pot pad.

http://i1084.photobucket.com/albums/j419/thisismyspace2/New%20G8/Brembo%20refurbishing/attachment_zps27f610e2.jpg (http://s1084.photobucket.com/user/thisismyspace2/media/New%20G8/Brembo%20refurbishing/attachment_zps27f610e2.jpg.html)


This is obscene. I love it!!!

[I12XLR8]

I was sure I read in this thread that someone claimed the 6 piston brakes would fit under the 19" stock rims and likely also the 18"s with a good spacer. I obviously read it elsewhere but what do you think? I can run 3/4" studded spacers and did with my 4 pistons...

[SweetG8]

Very nice!! ... Ok I would like to do this upgrade CTS-V 6 piston fronts and as you are saying Camero SS rears? Also what size rotors? From what I have read, I am thinking a 14" on the front? The rear you say a blank HSV... would that be a 12.76"? Also letting you know my car is a base V6 ......Any info very helpful thank you

[RaptorGXP]

My ccw rims barely clear my gxp brembos as the wheels were designed for the gt. I run an 8mm spacer and cannot go any bigger or the wheels will stick out of the fenders. Do u think the 6pots will clear my wheels?

[BuildItYourSelf]

I think the 6 piston calipers give more clearance then the 4 piston
I'm not 100% sure on that but the pistons are smaller and shorter in the 6 so I would assume the casting is thinner.
I read it somewhere on a CTS forum I believe. They said they went to the 6 BC the 4 rubbed a little.
It was a v1 he did it on.

[BuildItYourSelf]

Very nice!! ... Ok I would like to do this upgrade CTS-V 6 piston fronts and as you are saying Camero SS rears? Also what size rotors? From what I have read, I am thinking a 14" on the front? The rear you say a blank HSV... would that be a 12.76"? Also letting you know my car is a base V6 ......Any info very helpful thank you

Order 2010+ ctsv front fittment and hsv rear.
The diameter is only one of many measurements that need to be meet to fit.

Search brambo hsv and read about the rears.
You seem to have a lot of questions that the search can answer.
If you don't like the forum search like me use Google.
Use it like this. Blah blah blah site:forum.grrrr8.net

[RaptorGXP]

I think the 6 piston calipers give more clearance then the 4 piston
I'm not 100% sure on that but the pistons are smaller and shorter in the 6 so I would assume the casting is thinner.
I read it somewhere on a CTS forum I believe. They said they went to the 6 BC the 4 rubbed a little.
It was a v1 he did it on.

Can anyone with 6pot calipers confirm this?

[Eidolon]

Can anyone with 6pot calipers confirm this?

In my experience, the clearance was about the same between the calipers and my GXP wheels. If there's a difference, I'd guess it's a millimeter or less. Then again, no reason to guess...

http://eidolways.com/images/G8/ctsvcalipers/caliperclearance.jpg

That's from my GXP wheel to a 6-pot caliper. So now if someone can do the same measurement on a GXP with stock brakes, we'll have an idea.

Regardless, I'd feel comfortable stating that if your wheels have enough space behind the spokes to clear the 4's, they'll also clear the 6's. Not sure about the other way around.

[BuildItYourSelf]

I believe the outer corner is where the space is saved.
So the other most edge away from the hub.