Overheating Pads (qfm A1rm)

[Equinox]

Hey all.

Today I went to Winton for the second time with my S14. It has R33 GTS-T brakes all round with stock rotors and QFM A1RM pads all round.

The last time I came and for the first two sessions today the brakes were great however around half way through the day my pedal started going soft and then began to studder. I came into the pits and had a look at the front discs. They were dark and had heaps of pad material spread over them. The near new (at the start of the day) front QFM pads were now down to indicators. The backs however were fine.

Now it looks to me that I've gotten these things way too hot. I was doing a warmup lap, 2-3 hot laps, then a cool down lap, then another flyer then retuning to the pits with another cooldown lap. Is this too much for a pad like this to handle?

Looking around various forums these seem to be advertised for basic track work. Should I be warming them up or cooling them down differently? My car is lighter than an R33 so someone running them on an R33 would have bigger issues I'd imagine.

For the record the splash guards have been removed however I have not made any custom ducting yet. (Apart from the stock air guides on the caster rods) There are also no shims/backing plates/etc on the pads and I'm running Motul RBF600.

[Moodles2]

I had same problem, new A1RM's up front lasted 80mins with the big UAS GTR brake air deflectors: (more details: http://www.skylinesaustralia.com/forums/Pr...&p=4903262# ). This is what jetpilot had to say on the issue: http://www.skylinesaustralia.com/forums/-t...t&p=4909159

[Equinox]

Hmm Interesting. Have you tried any other pads since to compare?

[badhairdave]

You've done nothing wrong. If you don't have a light/low powered car they really aren't up to the task, particularly on a track with reasonably big stops like winton.

I would look at something with a higher temp rating that is more targeted towards track work. The comment about switching pads for street/track is bullshit btw. Project Mu HC+ are about the best street/track pad you will find. They aren't the nicest things on the street (they will squeel at low speed and light brake applications and they don't feel great when cold but still pull you up ok) but you will not overheat them on the track and they will last a lot of track days. As a bonus they give a lot of feed back and feel pretty good too.

I've seen comments about excessively high rotor wear but haven't seen it on stock nissan rotors (on a mates car) or on my SCR pro's. I got 8 full days out of my last set of HC+ pads with about a years street driving before that. My mate has probably done more than 8 days on his by now. Neither of us are particularly slow.

[Equinox]

A friend who was there in an Evo doing similar times to me (with a heavier car obviously) was using them and said they were great. May have to look into importing a set.

[badhairdave]

Local suppliers are currently listing lower prices than yahoo for a change. Dunno if it just hasn't been updated or they bought bulk stock during the 100Y-$ times.

http://www.project-mu.com.au/en/products/pad_hcplus.php

http://hioctaneracing.com.au/eshop/product...roducts_id=1145

[Equinox]

Hmm Nengun lists them at $294 delivered. Thought Yahoo Auctions + delivery would be probably be a bit cheaper again.

Guess I should support the local industry though!

[badhairdave]

Shit! Their price has certainly dropped since i last looked.

[Russman]

I just got the QFM A1RM's and they went well at sandown. Greg was very helpful and delivery was only 2 days.

Very cheap for $130. I don't think I'll be spending big on pads again after how they performed at Sandown.

I will monitor the wear but I get to about 220kmh before jumping on the brakes and they felt similar to my DS2500's.

^^This is what I thought^^ and my car would weigh about the same as an S14.

I have RDA slotted and dimpled 310mm rotors.

Sandown has much more heavy braking than winton too. Maybe more cool down on the straights though...

[Equinox]

Strange. Don't know what I was doing! It's on both sides of the car and all four pads so I doubt its sticky pistons.

I did a 1:41.8 and the car has 220rwkw ish.

[Russman]

Strange. Don't know what I was doing! It's on both sides of the car and all four pads so I doubt its sticky pistons.

I did a 1:41.8 and the car has 220rwkw ish.

I'll keep you updated as I go. I'll have a look to see how much mine are worn after yesterday. (My first day on them)

How did you bed them in? how many laps do you reckon?

I bed mine in over about 3 laps and then leant on them pretty hard and they were fine.

[gslrallysport]

As I said in that post that Moodles quoted, the A1RM is a street pad, capable of light track work. It's not a dedicated track pad. If you want to do serious track work, step up to something like the QFM Comp 9, $179 per axle set, and is a Ferodo DS3000 equivalent pad. As apposed to the A1RM which would be a Ferodo DS2500 equivalent pad....

I would look at something with a higher temp rating that is more targeted towards track work

That's not correct. Cast iron goes through a significant structural change at 723°C. If your rotors get hotter than that, they'll be quite a different material when they cool down. In technical terms, they'll be "fscked". Google for "iron phase diagram" for more details.

It's all quite irrelevant anyway, because it's uncommon to get rotors really glowing (=around 600°), even on a track. Claims beyond that are pissing into the wind.

The thermographic paints like what DBA use on their high-series rotors are a good idea. They tell you what temperature your rotors have been, not what temperature they are now. http://www.dba.com.au/2006/techdocs/T027.asp . Note that they don't bother measuring rotor temperature over 630°; if you get that kind of rotor core temperature your discs are rooted - that's probably getting to the magic 723° in the rotor cheeks. So... what's the point of a friction material that's "rated" higher than that?

So just be weary about what benefits you're getting from a pad that claim to work far higher than any rotor will physically get. Track pads don't have sky high temp ratings, and if they do, they've simply started a pissing contest with their competitors... What track pads are is a heavier duty versions of compounds designed to withstand sustained heat. The A1RM is a great cross over pad, but if you're serious about track work, step up to something like the Comp 9.

[Equinox]

What would define as 'serious track work' though? It's a street trimmed S14 on Semis doing no more than 3 hot laps in a session.

I might leave these on the back and look into a better pad for the front. (Off to Japan in 2 weeks so might grab some Mus while I'm there)

[badhairdave]

As I said in that post that Moodles quoted, the A1RM is a street pad, capable of light track work. It's not a dedicated track pad. If you want to do serious track work, step up to something like the QFM Comp 9, $179 per axle set, and is a Ferodo DS3000 equivalent pad. As apposed to the A1RM which would be a Ferodo DS2500 equivalent pad....

That's not correct. Cast iron goes through a significant structural change at 723°C. If your rotors get hotter than that, they'll be quite a different material when they cool down. In technical terms, they'll be "fscked". Google for "iron phase diagram" for more details.

It's all quite irrelevant anyway, because it's uncommon to get rotors really glowing (=around 600°), even on a track. Claims beyond that are pissing into the wind.

The thermographic paints like what DBA use on their high-series rotors are a good idea. They tell you what temperature your rotors have been, not what temperature they are now. http://www.dba.com.au/2006/techdocs/T027.asp . Note that they don't bother measuring rotor temperature over 630°; if you get that kind of rotor core temperature your discs are rooted - that's probably getting to the magic 723° in the rotor cheeks. So... what's the point of a friction material that's "rated" higher than that?

So just be weary about what benefits you're getting from a pad that claim to work far higher than any rotor will physically get. Track pads don't have sky high temp ratings, and if they do, they've simply started a pissing contest with their competitors... What track pads are is a heavier duty versions of compounds designed to withstand sustained heat. The A1RM is a great cross over pad, but if you're serious about track work, step up to something like the Comp 9.

Hang on, lets just clarify:

Your now claiming the A1RM is a street/light track pad (with a temp rating of 0-780 degrees?) and anything with a sky high rating is just a pissing contest between manufacturers?

And that rotors shouldn't go over 723 degrees anyway? "So... what's the point of a friction material that's "rated" higher than that?" I hear you say...hmm, better re assess that 780 degree rated street pad i was considering.

You recommend these pads for just about everything yet you never give a straight answer when someone has an issue. You answer with positive spin.

I'm actually genuinely interested to know the reason for the rapid wear some people are experiencing. I'm also interested to know, in general terms, how many track days people are getting out of a set so i can determine if they actually are a bargain, or if they are buying 3 sets to every 1 of a more expensive pad.

Russman, I'm interested in your feedback

[Equinox]

Here's some pics by the way. I left them at full resolution so you can see details easily. Assumed most people have a decent internet connection these days.

Front:

http://www.users.on.net/~logon/cars/progress/DSC00875.JPG

http://www.users.on.net/~logon/cars/progress/DSC00876.JPG

http://www.users.on.net/~logon/cars/progress/DSC00877.JPG

Rear:

http://www.users.on.net/~logon/cars/progress/DSC00879.JPG

[gslrallysport]

Hang on, lets just clarify:

Your now claiming the A1RM is a street/light track pad

Yes, and always have.

anything with a sky high rating is just a pissing contest between manufacturers?

Correct. If you think a 'track' specific pad that's rated to 900-1000 degrees C, if ever going to see it, then you need to do some serious analysis to what happens to rotors LONG before that temperature... Top temp rating is not what defines whether a pad will withstand track work or not. There's a reason why rotor thermal paints never show more than 630 degrees.

You recommend these pads for just about everything

No, we recommend these pads as a Ferodo DS2500 equivalent. That is, a 100% streetable pad, that will withstand light track work. And that's what they are.

If you're willing to run a pad that's less ideal for street use, that is, higher rotor wear, more noise, less cold bite etc. then there are pads above A1RM, like Comp 9 and 12 for the front, and Comp 2 and 6 for the rear. The Comp pads are $179 per axle set front or rear, or alternatively we can also supply Project Mu HC+ for $309 per front axle set. But we'll always recommend the A1RM first to people, because anything higher than that starts to become a compromise on the street.

[ssxRicho]

did you bed them in?

i found they last and perform much better if you go out hard for two laps when they are new (no track day before), come in.

let em cool for as long a possible. then go out again.

there is a HUGE difference.

if you heat em up and dont let cool from new (no track day before), you get the shudder and blue around the rotor. i did this the first time

only got 3 track days. the last set did 4 i think, had another day left.

oh ive got a 33 with 324mm uas caliper adapters and standard calipers. did sd last saturday 30+ deg outside. no pad problems.

oh and the uas air deflectors and no backing plate/ dust covers.

[siksII]

Hang on, lets just clarify:

Your now claiming the A1RM is a street/light track pad (with a temp rating of 0-780 degrees?) and anything with a sky high rating is just a pissing contest between manufacturers?

And that rotors shouldn't go over 723 degrees anyway? "So... what's the point of a friction material that's "rated" higher than that?" I hear you say...hmm, better re assess that 780 degree rated street pad i was considering.

You recommend these pads for just about everything yet you never give a straight answer when someone has an issue. You answer with positive spin.

So at least its not just me who has noticed!

Looks like the only people who see through some of the claims are those genuinely need a very high performance pad ie. not many of us. Meanwhile, the majority are ready to shoot the non believers down since they dont know any better.

I think jetpilots claims are more realistic nowadays, but plenty of questionable information has already been spread.

Personally I think temp ratings for pads are useless since there are rubbish performance pads that make big claims.. Although, would it be correct to assume the pad gets hotter than the disk? If so, then high temp ratings for pads might not be that silly if they ratings are comparable and realistic.

[Equinox]

Yeah I did bed them in. Bedded them in on the street and did another track day on them as well. (Where I didn't brake as hard)

They were bloody hard to bed in though!

[Russman]

What do you mean they were hard to bed in?

I looked last night and there was reasonable wear considering about 10-12 hard laps at sandown.