Z32 Calipers Question.

It seems that stock Z32 calipers don't like getting hot and on fire and I have therefore destroyed them again - not more than 6 months after my list caliper rebuild *sigh*.In the short term I have put some other Z32 calipers on. I have noticed though that on the outside near where it says Sumitomo, there is a number there. On my old calipers it says 2. On the new calipers, it says 3. Anybody got any idea what this number is?Having Sumitomo on them means that they are an alloy caliper yeah?Thanks.

 

What did you do to get them on fire? (n/m)

N/M

 

Track work.

I'll post pics later this evening.

 

Still saving for those 6 potters then eh? (n/m)

N/M

 

Considering it...

...but I want something more suited to track work than a zed.

 

!!!

I have slotted OEM front rotors and braded brake lines, and I was running it hard with a lot of heave braking for an extended period of time one night, we won't say where And it never faded, or any thing. It held up goodBut you must have got some serious heat for them to catch on fire!!!!
Was it the pads that caught on fire or the actual caliper?

 

Rode all 4 rotors like an old lady he did (n/m)

N/M

 

It was the inside of the piston...

...the back of the pad.
In all seriousness, you will never ever get the same heat in brakes on the road as you would on a track - even the famed OBrien Rd doesn't get my pads smearing when I go hard!On the track, its pretty much 100% throttle then 100% brake continuously and that 100% throttle isn't long enough for the brakes to even catch a breather.Apparently from 200m away on a side view slowing into a second gear 60kph corner, you could see front and rear rotors glowing brightly.I had ELF brake fluid in there... its meant to be a really light aqua colour.... after bleeding them last night... saw they are more a dark olive now - I'd say it got fairly hot! :-0

 

Do you have access to that heat paint? You >

could use that to check your brake temps.

 

I can get access...

Apparently melting point of pistons is 1350 degrees celsius? Can anyone confirm?
 
2 of my pistons have siezed and are all warped when looking at the inside of them :  
Possibly a good warning to others - when doing track work, don't do more than about 4 laps and give the brakes plenty of time to cool down!!!

 

My callipers had Sumitomo on them

and they are alloy. Later models used cast iron to prevent the calipers warping. Maybe a little bit of brake fluid is leaking past the piston seal and hits the rubber boot which catches on fire. You might need a caliper rebuild with new pistons if they have been heat cycled too much.

 

The brakes got rebuilt a few months ago...

...I know I definately wasn't losing any fluid anywhere. Pure and simple, they simply got too hot. :|

 

holy crap they caught fire!!?? were the

calipers painted by any chance?

 

What track:?)

Even on Wakefield Park (where there isn't much cooling time) the brakes don't get that bad. I did have smoke coming off my front brakes coming into the pits once, so I just drove round the pit garages for 5 minutes.What pads were you using? And what rotors?

 

They were... the black is kinda faded now! (n/m)

N/M

 

New AHG Driving Centre in Perth.

12 corners in under 2kms. Each corner is different, slowest corner is about 60kph. Fastest corner is about 150, hit 200 down the straight, average speed would be 100kph. Track goes down the straight, into the fastest corner on the track then straight into the slowest which is what really kills the brakes.I've had smoking on some of the more enjoyable roads and without fail around the track. The worst thing is then parking it when the rotors are hot - as they cool down, the pads hold heat in at that part of the rotor making the rotor cool at different rates and thats how warping and cracking occur.Standard rotors (with surface cracks) and was using Bendix Ultimates at the time with Elf Dot5.1 racing brake fluid.

 

maybe try some track pads

I found the bendix ultimates to smoke when pushed really hard at the track, EBC yellows seem much better. The standard rotor/caliper combination is pretty borderline when it comes to pushing really hard at the track, thats why I upgraded to the Stoptecs.

 

I've had EBC Reds before.

Along with some testing some beta RG race carbon metallic pads.I find the Ultimates are a good compromise between road and track. At the end of the day; the zed is a big fat heavy car and its gotta be lived with.

 

Ive used the reds before too

and they were very ordinary, only lasted 2 track days and didnt like the high temps either. I think they are popular with the WRX track guys, but WRX's are alot lighter than zeds. Ive found the yellows to be much better and last for ages too.

 

I haven't gone to that extent...

...but Im thinking I might try them... few track days coming up soon!