richscorvettes

I'm installing the Carbotech ceramic brake pads and it seems like a pretty straight-forward job. I did encounter a few interesting things though which I wanted to mention and seek the advice of anyone who has switched pads on the C7.

- When removing the rotors for painting I noticed that the front caliper bolts appeared to have Loctite applied. Interestingly though the rear caliper bolts did not. I wondered if that was just missed (which I doubt) or done for some reason. I've always used blue Loctite on the other Vettes and am inclined to do the same on this one.

- I couldn't find a specific reference to the caliper bolt torque for the C7 but believe that the 125 lb.ft. I've used on the C5 & C6 would be the correct value.

- I found that the rear pads could be changed with the calipers and rotors left in place. It was pretty straight-forward just by driving out the retainer pins and moving the caliper pistons back a bit. When I tried to do the same on the front I found that the pad wouldn't slide out. After removing the caliper I found that they use a type of double-sided tape. With the caliper off the pads came out okay but no doubt GM used the double-sided tape for a reason. I haven't found any reference to that on the Brembo web site and wondered if the tape should be reused.

- I also noticed that the design of the stock front pads is quite a bit different as the GM pad has what appears to be two "weights" which possibly could be to better balance them to avoid brake noise. I'm not sure that is an essential feature but it does make me wonder.

I would be interested in any thoughts from those of you who have changed the pads. Thanks,

Rich

Motohead279

im interested in this thread because I have some carbotechs on order myself.

*C7*

Rich, I changed my pads this past weekend and found everything in your post to be exactly the same as my experience. I cleaned the tape residue on the fronts and put the pads in with no tape or weights.

richscorvettes

Thanks for the feedback. I'm told that the "weights" are intended for noise reduction but, since these are performance pads, they aren't used. Since the Carbotech pads don't have a provision for the weights to be installed you can't use them in any event. Let's hope that the pads work well without them.

I remember in the "old days" that we used to use a type of silicone membrane material on the backside of the pads to help avoid squeaking. Other than a little grease on the bottom edges of the pads where they contact the caliper it seems that nothing is used these days. I have heard of some folks using a little grease between the pad and caliper piston but would be concerned about collecting dirt so I don't plan to do that.

I do plan to use the blue Loctite on the caliper bolts as I've always done that and think it could help some.

I'm taking pictures and notes on the installation and will have them available should anyone be interested in what was involved.

As always, I'll appreciate the thoughts of anyone else who has done this job. Thanks.

Rich

jwbert

I thought I read in the manual that torque on the caliper bolts
was to be 155 ftlbs?

0Anthony @ LGMotorsports

Front and rear pads both can be done with the calipers on.

Brembo has almost a complete tool free design on them. There are two pins in the top of each caliper that you can knock out with a drift and small hammer. The pad spring clip at the top will apply some pressure to them so you will push that down slighlty to get it out.

I did see on our car that the front pads had a sticky piece to the back of them...possibly for install at the factory so they didn't fall out.

Either way, you can do pads without pulling the calipers on them.

Caliper to upright bolts should be loctited.

richscorvettes

Thanks for the feedback.

I used the blue Loctite on both the front and rear caliper bolts. I thought it was odd that the factory seemed to have used it on only the fronts and wondered if they had a specific reason for doing that.

I used the 125 lb.ft. torque setting for the caliper bolts. Is that the value you use?

The Brembo design is well done and changing pads is much easier than when we did them on our C6 Z06. I had wondered though why they had used the tape on the front pads but your thought is most likely why they did it.

I've usually used a brake specific lube for the metal surfaces on the pads and, on some cars, a "brake-quiet" product for the rear of the pads. I didn't this time since the feedback I've been able to find indicated not to use brake-quiet for pads which use a spacer. Any thoughts on what you use, if anything, for those?

Thanks again,

Rich

0Anthony @ LGMotorsports

I would honestly have to pull the book on the C7 to see exact specs on this car. The C6 cars however I want to say it was 95 ft-lbs...on track cars I used red loctite on them, not really something you want coming loose.

Race cars I don't use any kind of lube on the back of the pads...I would not get carried away with that stuff. I don't like using spacers on them or any kind of plate between the pad and pistons as they can and typically do cause a spongy pedal...something we ran into with some of the race cars with Ti backing plates for heat protection.

KNSBrakes

Like to see some pics of the factory pads.

As far as glue, grease and noise - hopefully lots of that is not required because on other Brembo equipped production cars it is a band-aid that works poorly and hence the 'weights' on the pads.

Hi-temp grease where the pads hit the abutment plates and clean pad pins is what I do. Hard to think grease or anything is really going to stay between a piston and shim or backing plate or provide any real damping.

Any feedback on noise/dust after the Bobcat install? Apparently the Z51 pad dust is pretty bad.

richscorvettes

Below are front and rear views of the C7 front brake pad.





You can see the weights used and also the double-sided tape. The rear pads look like most other pads and do not use weights.

Below is a close-up picture of the rear caliper with the stock pads installed.



Below is a picture of the new pads installed and the painted rotors.



The brake grease I've used in the past (sparingly) is from CRC or Permatex but there are many brands out there. For the rear of some pads I've used the "anti-squeal" material such as that from CRC. It's not really a grease but more of a thin membrane once it dries. For this pad change there was enough brake grease already on the calipers so I didn't add any. I also didn't use the anti-squeal on the rear of the pads since the information I've found suggested not to use it for a pad which also uses a shim which is the case with the Carbotech pad.

When it comes to the torque value for the caliper bolts the Service Manual for the C6 indicates 129 lb.ft. I haven't seen a C7 specific service manual yet but believe the same torque setting would be used.

With our current weather we haven't been able to take this car out to try out the new pads yet. I can say though that we used them on our C6 Z06 for street use and they performed very well, there was no noise, they wore well and the amount of brake dust produced was significantly less. Our positive experience with these pads on that car was the reason I decided to change them on this one.

Rich

KNSBrakes

Great pic - thanks


Pads made by Ferodo for Brembo/GM.

Looks like HP1300?

FF Friction code - pretty normal for a street pad. That FF designation indicates a pretty wide range but is where most pads fall. Ceramics are sometimes EE, HP+ are GG etc.

For a car that is said to be for the track - I wonder what happens to that plastic tape stuff? Yuk/mess

Nice rotors!

richscorvettes

In addition to the "FF" code there are three numbers on the pad. One is: "HP1000/1" and another is: "0787153000". The former may be for the backing plate and the latter for the rear "shim". Interestingly, the shim appears to be made from a hard, thin rubber type material rather than metal. That same type of pad is also used on the rear pads. It's possible that those are intended to serve the purpose of cushioning the brake pads and possibly helping reduce noise or squeal. The third number is on a label attached to the double-sided tape which reads: "87153000". I'm guessing that is the part number for the tape. It wouldn't be hard to imagine that high temperatures could eventually destroy the tape and possibly it was only used as Anthony speculated to keep them in place during assembly.

One other quick observation is that the stock front pads have wear indicators on both the outer and inner pads while the rear has one only on the outer pad. The Carbotech pads only have them on the front and only on the outer pad.

As I've often said, "I've already told you more than I know" so I'll stop speculating now........

Rich

KNSBrakes

HP1000 is the Ferodo street compound. The number is probably a production date code and/or other info that OEM stuff requires. ::Speculating myself!::

And the older Brembo equipped cars do have a similar shim type. That would be Brembo's admission of noise issues

GazUK

Rich, great thread/detail, thank you.

I'm looking forward to your review of the new pads, and how much less break dust is generated.

richscorvettes

It will be a while before our weather clears enough to get the car out again. But, I can say that the Carbotech 1521 pads worked great on our Z06 and I expect them to work as well on the C7.

Changing the pads on the Brembo brakes is very straight-forward. Just drive out the retainer pins with a drift, compress the caliper pistons a bit, remove the pads and reverse the process to install the new pads.

You do have to be sure to fully seat the retainer pins especially on the rears since those are recessed a bit. The retainer pins stick out above the surface on the front calipers which makes those easier. You will feel and hear a distinct "thunk" when they are fully seated. You will also see that the front side of the pins stick out a bit on the caliper.

The only other aspect to look for is being able to get the front pads out because of the double-sided tape they use on those. I removed the front calipers to make that easier to do but I suppose you could slide a putty knife between the pistons and stock pads to get them out without having to remove the caliper. Removing the calipers did though make it easier to check for and remove any residual tape glue.

You can see a better view of the pins in the two pictures below. One is the driver's rear and the other the driver's front caliper:





Rich

descartesfool

On track, it's just going to burn away.

The Brembo clips not only help noise issues, they also prevent pad knock-back, which can be an issue on track if the pads move away from the disc down the straights and when you step on the brake pedal, there is a little slack to be taken up to get the piston, pad and disc all touching, which causes a slight delay in brake effectiveness. On a GT-R with 6 piston Brembo calipers, there is only one clip, but factory recommends a second clip be installed for track use. This is not an option on the C7 brakes as the clip covers the whole of the caliper opening.

So is there a torque setting for the C7 calipers? Guessing torque settings is not always the best choice.

richscorvettes

In searching for service specifications on the torque values I could only find references to those used for the C6. I also found that the C7 Service Manual apparently won't be available until early April. But, not being satisfied, I did get in touch with a GM technical source who looked it up and said the caliper bolt torque should be 162 lb.ft. for the C7. He had no idea why the value has changed but it may be as simple as that being the value that Brembo specifies. So, I've had to adjust my initial setting to the new value.

Rich

descartesfool

162 ft-lb seems very high for a bolt torque. Might consider checking again that it is not 162 Nm which would be 119 ft-lb.

KNSBrakes

Isn't 119 lb-ft what the C5/C6 are?

KNSBrakes

And if it is that high I'm buying the time sert kit now. The Subaru guys are constantly seizing/stripping the Al threads in the caliper. Granted they likely see more inclement weather but it's quite frequent.

If I recall - the Subaru torque was spec'd at like 140 lb-ft. Pretty high for an M12 bolt