[SEAT TIME RULES]

Anyone with this front BBK chime in on pad rattling? I put some R4 pads in per the size they recommended and they're shape and size allow them to move around some. I run R4's because they are an excellent track pad that will not eat your rotors when they're cold, or street driven.

[ZM2]

Did you get these?

https://www.essexparts.com/essex-des...p9660-calipers

[SEAT TIME RULES]

Originally Posted by ZM2

Did you get these?

https://www.essexparts.com/essex-des...p9660-calipers

Yes I did..that's why I'm baffled on the noise..

[jritt@essex]

This issue is as much pad-related as it is caliper-related, and there are a couple things going on:

The AP Racing calipers are extremely consistent with how much room they have for pads. That said, they need to be large enough to accommodate a very wide range of pads from a long list of pad manufacturers. That means the calipers cannot leave so little room that you're hammering the pads into the openings. They need to be able to slide freely as they wear, and they also need room to expand and grow when they're heated to track temperatures.

On the pad side, every pad manufacturer makes their pads a different size spec. We see differences of up to a couple mm in either length or height. Some of that has to do with the pad compound. A sintered pad for example, tends to grow more when heated to track temps, so they're manufactured smaller to give room for that expansion.

In summary, you're going to see different fitments with different pad brands. No two are the same. The versatility of the AP calipers is also a negative from the NVH standpoint in this instance. Some pads from some manufacturers will slide in very easy, while others will be a bit tighter. It could just be that the R4 pads were manufactured on the smaller side of the spectrum for pads that 'fit' the AP caliper, so they have more wiggle room. That said, if you were to get a different set of the same R4 compound, they may move less as there tends to be variation in pad backing plate size across different batches. Manufacturers will have a range of acceptable spec, so even different pad sets from the same manufacturer in the same compound will fit differently!

In terms of noise, you have two planes on which noise can be generated: vertical or Horizontal. Vertical would be up and down when you go over washboard ripples in the pavement...more of a 'rat-tat-tat-tat' repeated sound. Horizontal would be more of a clunk when you switch from reverse to forward and back again. The pad slides from one end of the caliper opening to the other generating a 'thunk'.

Under what conditions are they making noise? Also, is this front or rear, and are you running the CP9660 or CP9668 front caliper?

We'll help you get to the bottom of it, whatever it may be. Thanks!

[SEAT TIME RULES]

I'm running the 9660 fronts...I'll drive the car again tomorrow and pull the rims as well. Appreciate your help with this, Great Follow up sir!

[jritt@essex]

Originally Posted by SEAT TIME RULES

I'm running the 9660 fronts...I'll drive the car again tomorrow and pull the rims as well. Appreciate your help with this, Great Follow up sir!

No worries! Feel free to call our customer support or email us if you want. We'll do everything we can to get you as noise-free as possible, regardless of what pads you're using. Thanks.

[mcvaughan]

Originally Posted by SEAT TIME RULES

Anyone with this front BBK chime in on pad rattling? I put some R4 pads in per the size they recommended and they're shape and size allow them to move around some. I run R4's because they are an excellent track pad that will not eat your rotors when they're cold, or street driven.

If you cannot get it sorted with the R4, look to the Ferodos. I have no rattling with DS1.11 and DS2500.

[SEAT TIME RULES]

Originally Posted by mcvaughan

If you cannot get it sorted with the R4, look to the Ferodos. I have no rattling with DS1.11 and DS2500.

Thats what I was thinking as well. I could leave the P4's on the rear axle and swap over to some Ferodo's

[ZM2]

The DS3.12 is pretty killer for the track, my new fav pad. Also no rattling.

jritt@essex is there a step up from the DS2500 that’s still tolerable on the street? I can get the DS2500 to fade when doing back to back braking during spirited drives.

I also cracked one on a day that started with snow on Watkins Glen and then a dry line formed mid session later in the day, and it couldn’t handle the heat going into the bus stop.

[SEAT TIME RULES]

Originally Posted by ZM2

The DS3.12 is pretty killer for the track, my new fav pad. Also no rattling.

jritt@essex is there a step up from the DS2500 that’s still tolerable on the street? I can get the DS2500 to fade when doing back to back braking during spirited drives.

I also cracked one on a day that started with snow on Watkins Glen and then a dry line formed mid session later in the day, and it couldn’t handle the heat going into the bus stop.

ZM2, are you running RE71's for your track days? On R compounds I can run any pad I personally like (Left Foot Braker) But on 200 Wear tires some pads will not match up well on the less mechanical grip tires...

Your thoughts?

[ZM2]

Originally Posted by SEAT TIME RULES

ZM2, are you running RE71's for your track days? On R compounds I can run any pad I personally like (Left Foot Braker) But on 200 Wear tires some pads will not match up well on the less mechanical grip tires...

Your thoughts?

I’m left foot, as well.

I could get fade on any street, R, or slick tire I ran even with DS1.11 (after 20min), but I’m pretty damn tough on my brakes and I still have OEM rear brakes. Albeit, with GT3 air deflectors all around and protection plate cut outs.

When I switched to DS3.12, fade went away for my setup regardless of what tire I ran. If you have AP’s all around, the DS1.11 is probably good enough, but I love the feel of the 3.12 more than the 1.11.

As for the DS2500 on track, don’t do it. My comment about Watkins was it only took a few laps of dry line in a hard braking zone to crack what is essentially a high performance street pad.

[SEAT TIME RULES]

Originally Posted by ZM2

I’m left foot, as well.

I could get fade on any street, R, or slick tire I ran even with DS1.11 (after 20min), but I’m pretty damn tough on my brakes and I still have OEM rear brakes. Albeit, with GT3 air deflectors all around and protection plate cut outs.

When I switched to DS3.12, fade went away for my setup regardless of what tire I ran. If you have AP’s all around, the DS1.11 is probably good enough, but I love the feel of the 3.12 more than the 1.11.

As for the DS2500 on track, don’t do it. My comment about Watkins was it only took a few laps of dry line in a hard braking zone to crack what is essentially a high performance street pad.

I'll run a high temp pad on track. As for my last post what I was talking about was having to much pad for the tires being used. It sounds like your not having this problem with your tire/pad setup. I had some Carbotech XP-12's on my Evo and when I was on my street tires the pads would induce early ABS. To much initial bite :-)

[ZM2]

Originally Posted by SEAT TIME RULES

I'll run a high temp pad on track. As for my last post what I was talking about was having to much pad for the tires being used. It sounds like your not having this problem with your tire/pad setup. I had some Carbotech XP-12's on my Evo and when I was on my street tires the pads would induce early ABS. To much initial bite :-)

Oh, nahh. The Ferodo’s have good enough feel & release that if you overcook it and ABS kicks in, you can let up a tiny bit to get out of ABS.

This also assumes you’re going 9-10/10 at initial application and also letting out as you’re slowing down, so your foot is already moving towards releasing coming up to the corner, so the adjustment is easy if needed.

Not saying you’re not doing that, just that some guys go harder & harder on the brake up to the corner vs actively managing the pressure.

Now, one could argue that if you’re already into the ABS, go ahead and use it for that braking zone bc modern ABS will do a better job than your foot will, but it’s a good habit to not rely on the ABS.

Now we’re getting into braking techniques, vs pad rattle issues.

[mcvaughan]

Originally Posted by ZM2

I'm left foot, as well.

I could get fade on any street, R, or slick tire I ran even with DS1.11 (after 20min), but I'm pretty damn tough on my brakes and I still have OEM rear brakes. Albeit, with GT3 air deflectors all around and protection plate cut outs.

When I switched to DS3.12, fade went away for my setup regardless of what tire I ran. If you have AP's all around, the DS1.11 is probably good enough, but I love the feel of the 3.12 more than the 1.11.

As for the DS2500 on track, don't do it. My comment about Watkins was it only took a few laps of dry line in a hard braking zone to crack what is essentially a high performance street pad.

I think the 2500 is fine on the rear — ran the same on my M4 with the 1.11s. You have me intrigued about the 3.12. I have not run the DSUno pad, but I understand they're tougher on the rotors, albeit with more initial bite vs. the 1.11.

[ZM2]

Originally Posted by mcvaughan

I think the 2500 is fine on the rear — ran the same on my M4 with the 1.11s. You have me intrigued about the 3.12. I have not run the DSUno pad, but I understand they're tougher on the rotors, albeit with more initial bite vs. the 1.11.

Good point, the 2500s probably are ok on the rear.

Altho, I like the same bite F&R. Plus, with my AP’s only up front & OEM brakes on the rear, I’ll take all the bite I can get in the back to offset some of the extra front braking power/bias.

I frankly never liked the UNO’s. Way too grabby, especially on release, and they burned up fast! I used a whole set in one weekend.

The 3.12s are pretty damn great. A little more bite than the 1.11s, but still a smooth release, long life, and consistent from cold to hot. I was really blown away by them.

[PLF69]

Any comments on Raybestos ST43 ?

Apparently they are smooth on rotors and very good.

[jritt@essex]

Originally Posted by ZM2

I’m left foot, as well.

I could get fade on any street, R, or slick tire I ran even with DS1.11 (after 20min), but I’m pretty damn tough on my brakes and I still have OEM rear brakes. Albeit, with GT3 air deflectors all around and protection plate cut outs.

As for the DS2500 on track, don’t do it. My comment about Watkins was it only took a few laps of dry line in a hard braking zone to crack what is essentially a high performance street pad.

This is really surprising, as it's very rare for people to actually fade the DS2500. We've had C7 Z06 on VIR with the DS2500 (accidentally ran the wrong pad), and they didn't actually fade them...just wore them out quickly. I've never heard of anyone ever fading the DS1.11.

ZM2,
Can you please elaborate on your GT3 air deflectors and 'protection plate cut outs'. Do you have any pics?

We've seen more problems caused by home-brew brake cooling mods than I care to count! A proper brake duct setup is extremely tough to implement on a road car for a whole bunch of reasons. I just want to investigate this on your car, as you could be hurting yourself more than helping. Your comments on fading pads don't jive with our data across a vast number of other cars. From everything we've seen, aftermarket ducts hurt our systems' cooling capacity more than they help it.

As a first step we always suggest removing the brake dust shields and not running any aftermarket ducting first, and checking temps. Then if you determine you need more airflow to the brakes, a careful implementation of a proper duct setup is required. Nine times out of ten, any type of plate bolted near the inside of the disc is only going to raise brake temps and accelerate pad and disc wear.

Glad you're enjoying the DS3.12!

[PLF69]

https://www.bimmerpost.com/forums/sh...php?p=24993475

I also ran them on OEM calipers with DS1.11 and all was fine (PSC2 tires) I think ZM2 is hard on his brakes

[ZM2]

Originally Posted by jritt@essex

This is really surprising, as it's very rare for people to actually fade the DS2500. We've had C7 Z06 on VIR with the DS2500 (accidentally ran the wrong pad), and they didn't actually fade them...just wore them out quickly. I've never heard of anyone ever fading the DS1.11.

ZM2,
Can you please elaborate on your GT3 air deflectors and 'protection plate cut outs'. Do you have any pics?

We've seen more problems caused by home-brew brake cooling mods than I care to count! A proper brake duct setup is extremely tough to implement on a road car for a whole bunch of reasons. I just want to investigate this on your car, as you could be hurting yourself more than helping. Your comments on fading pads don't jive with our data across a vast number of other cars. From everything we've seen, aftermarket ducts hurt our systems' cooling capacity more than they help it.

As a first step we always suggest removing the brake dust shields and not running any aftermarket ducting first, and checking temps. Then if you determine you need more airflow to the brakes, a careful implementation of a proper duct setup is required. Nine times out of ten, any type of plate bolted near the inside of the disc is only going to raise brake temps and accelerate pad and disc wear.

Glad you're enjoying the DS3.12!

Yeah, I've always been tough on the brakes. It's where I make most of my time up on track vs other guys around me.

For background, I color shifted my stock blue brakes with PFC 08s on just their second day. No cooling mods at that point.

And, agreed on your thoughts regarding homebrew brake cooling mods, especially on street cars. That's why I only cut away some of the protection plates to point air into the center from the GT3 scoops: https://f87.bimmerpost.com/forums/sh...0&postcount=16

The scoops did help on my next outings, but I still would get fade so I moved to the AP's.

The AP's work great, but as I added power and more rubber I would get fade with the 1.11's after 20-25min on hot summer open lapping sessions when I was pushing it. If I backed off a lap, the pad fade would go away.

I've added more power since then and the 3.12s have still never faded on me, but I eventually need to get some AP's on the back to help out...

[Lienrocs]

Originally Posted by ZM2

The DS3.12 is pretty killer for the track, my new fav pad. Also no rattling.

jritt@essex is there a step up from the DS2500 that's still tolerable on the street? I can get the DS2500 to fade when doing back to back braking during spirited drives.

I also cracked one on a day that started with snow on Watkins Glen and then a dry line formed mid session later in the day, and it couldn't handle the heat going into the bus stop.

Where'd you get the 3.12's from and how much did they run you?

[ZM2]

Originally Posted by Lienrocs

Where'd you get the 3.12's from and how much did they run you?

My shop procured them—I always like to let them make a little cash off parts if they sell them at normal market pricing. They were $450 or so, I don’t quite remember.

And, I’m pretty sure they got them from Essex.

[Lienrocs]

Originally Posted by ZM2

My shop procured them—I always like to let them make a little cash off parts if they sell them at normal market pricing. They were $450 or so, I don’t quite remember.

And, I’m pretty sure they got them from Essex.

Awesome. Is that fronts only? Good to hear some positive feedback about them.