daveh

iTrader: (9)

I have finally found a rear pad that will stand up to my abuse. I was previously getting 1-2 days out of my R4 track pads in the rear. Per recommendation of Tim at porterfield and my local race shop, I tried the new Raybestos st43 race pads.
Since I still have a couple days left on my front R4's I only got the st43's in the rear just to see if they would take the heat and last more than 1 day.
Well the answer is yes they will take the heat. They wore very well after 1 day at thunderhill. Granted the hill is not very hard on brakes, the pads only wore 1-2mm or so. I think I will easily get 4-5 days out of them. Rotor wear was also decent for a track pad. But the flip side is that they took so much heat, I melted my rear piston boot!
Has anyone else run into this? I finally find a pad that will work and now this.

In terms of bite and feel, the raybestos were awsome. They had tons of bite. Even with only the rears installed, I almost went through the windshield the first time I hit the brakes. They defninately took some getting used to. They take a little longer to get up to temperature compared with the R4's and had tons more bite. They almost had too much bite but the release characterisitics were very smooth and were fairly easy to modulate once you got used to the initial bite. I was setting off abs in the rears with my newly found rear bias. Its hard to give a more detailed review since I had mismatched fronts but I could feel the above differences with the rears in there.

I've got a couple days left on my fronts so after that I'll be switching to the st43's up front as well. Some people are running the st41's up front with the 43's in the rear, but they said the 41's have even more bite and are trickier to modulate.

bigdaddy

iTrader: (3)

i melted my piston boots a long time ago. it won't be a problem as long as you make sure to check that the pistons are clean when you are in there changing pads.

stumpmj

iTrader: (1)

Once you melt the pads steel backing plate, then you're actually using the rear brakes

Thanks fo rthe recommendation on the pads though. How much did they cost you?

dnguyent

iTrader: (5)

Any idea whether titanium backing plate will help at all? I can't recall it they're available for the rear, but if not, it doesn't seem like a difficult item to fabricate/cut. It seems like those rear brakes could use all the help they can get even if it means paying $50+ for a bunch of thin titanium plates.

On the same note, do race teams use titanium backing plates?

daveh

iTrader: (9)

Yeah, any time you involve heat, melting, explosions, you're definately doing something cool.

The pads are $211 front and $119 rear (custom cut) from porterfield witht he %15 NASA discount. They are expensive but if they last twice as long it all evens out. Wait unit I try the fronts in conjunction with the rears on memorial day weekend before making any purchases. All I know for sure right now is that the rear pads didn't burn up at a track that's not too hard on the brakes. If they show any signs of damaging parts of my stoptech up front, they won't be my pad of choice.

I spoke to the good folks at stoptech about titanium backing plates for the rears and they hadn't really thought about it until our conversation. Matt said he will start looking into it because it sounds like something that us Z owners could use. He is checking for me if it is possible to use the backing plates from their front kit and cutting them to the rear size. He wasn't totally convinced that the backing plate would have kept me from melting the rear piston boot though.

Stay tuned for my full review in a couple of weeks when I try the st43's on all 4 corners.

Kolia

iTrader: (2)

Lucky you didn’t leak any oil from that caliper! Fire is not good for a car…

As for the backing plates, when I was in Italy I tried an interesting setup. A friend who manages a fleet of Group N rally cars found a type of waffle like asbestos core sandwiched in steel sheets. The whole thing was ~3mm thick and would collapse the first few times so the initial pedal travel was a bit annoying. Yet, it completely eliminated brake fluid fade. The down side was all the heat would stay in the rotors. Cool down laps are then super important.

I’m not sure that material could be found here…

stumpmj

iTrader: (1)

I'd stay away from the backing plates. Keeping all that heat in the pads will just make pad life shorter and increase the chance of damaging something. If you use high temp fluid, there's no need for the backing plates.

Nano

iTrader: (1)

Yeah, I thought brakes on serious track cars didn't use either backing plates or rubber boots. As both only trap heat.

Kolia

iTrader: (2)

Serious race cars are not used every day on dirty roads and require lots of maintenance...

And they don't weight 3300+ lb either !

dnguyent

iTrader: (5)

As I see it, I would only justify the use of backing plates if it protects the dust boots. I haven't boiled my fluids yet, and I actually doubt that it'll be a problem for me since I'm running the 14" stoptechs (most track junkies say it's overkill). Most of us don't have the time to dismantle and overhaul calipers to replace melted dustboots. Avoiding or delaying that process alone would justify my expenditure on backing plates.

In some ways, I'm glad I got the larger BBK, but its effect on accelaration is certainly noticeable.

Nano

iTrader: (1)

Backing plate and dust boots trap heat whether you race in grand am or lap once a month with your street car. The principle is the same.... (if the car weights 3300lbs, it's even worse actually )

IF you get to the level you melt the dust boots/backing plate, you are serious enough and might want to consider getting rid of either the dust boots or the backing plate... or both. And accept the extra maintenance that comes with it...

I don't think a titanium plate would be a very efficient idea. As stumpmj said, the weakest link failed... now you are trapping even more heat so a) risk having something more critical fail b) reduced overall efficiency of brakes

Kolia

iTrader: (2)

The dust boot has nothing to do with heat management.

In Daveh's situation the problem was too much heat transfered to the caliper. So we have to either get rid of it faster (improved air flow), isolate the caliper better (backing plate on the pads) or generate less heat all togheter (bigger discs, bigger pads).

Anyways, can't wait to hear the full report on the pads.

Nano

iTrader: (1)

How is "too much" heat transfered to the caliper not an heat management issue?

I don't recall titanium being an effective heat insulator. As I said, the way I understand it, a titanium plate risks trapping even more heat and risk damaging not only the dust boot, but the caliper... your waffle thingy makes more sense to me... but still risks trapping heat in the long run it could even be worse.

I don't know that's how I understand it. I'd rather let the dust boot die if that's the only side effect.

Kolia

iTrader: (2)

The dust boot does not transfer heat, it just prevent the pistons surface from contaminant. That's what I meant.

We're polluting a serious topic now...

Nano

iTrader: (1)

I don't think that we are poluting. The melted dust boot was an issue of the raybestos pads.

The dust boots does not transfer heat, it just traps heat. My point is that melted dust boots are not a big deal and people shouldn't worry too much about that. THey might want to consider more maintenance once they have failed. And I thought the titanium plate idea was silly.

If I am poluting, sorry

Kolia

iTrader: (2)

I don't understand how the rubber boot would "trap" heat ?!

The titanium plate would isolate the piston from the pad. Heat does not trasfer very well at the interface between the pad and plate and piston. So it would help.

The asbestos waffles where a bit to efficient. I'd actually be worried of burning the wheel bearings...

About the added maintenance. I'm curious who here would take his calipers appart for cleaning on a regular basis ?

Nano

iTrader: (1)

dust boots trap heat just like any lid would trap heat. Dust boot have tendency to fail. I haven't met an instructor who hans't had problems with them at one point or another. I know some who do not use them. I know track variants of brembo, stoptech, wilwood do not have them as they will inevitably fail.

Maintenance is not as bad as it seems. Certainly not as bad as replacing dust boots after every event.

I still not sure about the backing plate idea, but if stoptech is considering it, there must be a base for it.

Kolia

iTrader: (2)

Since we're on the subject...

That was at Misano two years ago...


Personnaly, I'll do what ever is necessary to keep my dust boots intact. Pads wear quickly enough as it is, I don't want the pistons to size up and accelerate that wear !

We'll see how the Brembo's do this week-end and the next, when I lap with the Azenis...

Nano

iTrader: (1)

Well, I checked zeckhausen website and these seem to have been available from quite some time for the front...

http://www.zeckhausen.com/Brembo/Con...s.htm#Titanium

available for both brembo and stoptech calipers

the question remains if this is a perfect solution, or just a compromise. I don't think track cars use them...

BTW, what azenis... size? model?

Kolia

iTrader: (2)

Interresting table comparing thermal properties of metal:

http://www.engineersedge.com/properties_of_metals.htm

Titanium is more than twice better to shield from heat than mild steel, while weighing half as much.

Only stainless steel is better, but since Titanium is so light, that benefit can still be offsetted by using a thicker sheet.

Titanium backing plates are not so "rice" after all...