Improving OEM brakes for track

[ChawenHalo]

Bonsoir Zedders.

Once I've worn out the OEM items I will want to change the pads (Ferrodos?) brake tube pipes to steel lined ones and perhaps the liquid.

Question - I understand the disks are the same as the CSL's brakes on the Z4MC but are too thin (4mn) to take regular and prolongated abuse. I'm thinking that maybe if I interfeer with the OEM set up then increased heat and pressure will crack them, in which case I might as well save and just go for the full monty (AP 6 pistons + 4 - which is just unnecessary for the emoment concidering I'm at the bottom of the learning curve oin track and am fairly careful and sympathetic.

Any advice sil-vous-plais?

 

[Beedub]

i feel your pain..... i balled out and went AP BUT..... i do have over 100bhp more than stock....

imo the stock brakes are very good but even on the small sprint track i use reguarly i could fade them very easily so decided to upgrade to the AP setup..... on removing my stock items i could see that i was damaging the stock items so i was happy to replace them and sell them while they were fresh and sellable still, luckily they are in service on a normal powered/driven car now so no doubt will last a long while.

i think SS lines, Uprated pads, and proper fluid, ATE superblue is awesome, i think you will still be able to overheat them but you'll get longer out of them, imo the stock items just need alittle sympathy and you'll be fine, but prolonged track use will KILL them!!

Needless to say i can now abuse my APs much more than stock, probably one of my best mods to this car!!

 

[ga41]

If you're out to put down as fast laptimes as you possibly can then you will cook the stock brakes easily. You will even do this on an upgraded stock system (pads, stainless steel lines and good fluid). If you are tracking the car for fun and are not really giving it 10/10ths then an upgraded system will do just fine.

I've got Axxis ULT pads, Goodridge stainless steel brake lines and Endless RF 650 fluid on mine. I could fade the brakes easily with the stock fluid on very fast mountain runs and on the autocross events i take the car too. I installed the pads as a "stock + a bit more stopping power" solution as soon as i wore out the stock ones and liked them for the price. The fluid i upgraded because i could feel a very spongy pedal after long mountain blasts and at the autocross events and i saw a very big difference, the lines i installed to get a bit more feel when braking heavily, you can't really tell a difference on the road but on the track i can feel an improvement there too.

Basically with the whole lot i'm now very pleased. More confidence to bring down my laptimes and prolonged endurance for my mountain runs which can run at 20+km of sustained acceleration/hard braking.

Doesnt mean i wouldnt install a big brake kit if i had the money lying around somewhere.

 

[Biscuits]

I'm off to the 'Ring and Spa in May and wanted to upgrade the brakes 'a little' as I'm not a regular track user. The OEM front disks were warped anyway, so a good time to get things done.

After consulting with http://www.bmsport.com I got replacement OEM disks and Padgid RS29 endurance pads fitted. Overall the pedal feel is much better, they perform well when cold and once warmed up seem to be better than the OEM pads (and so they should at the price!!!)

 

[ChawenHalo]

i feel your pain..... i balled out and went AP BUT..... i do have over 100bhp more than stock....

imo the stock brakes are very good but even on the small sprint track i use reguarly i could fade them very easily so decided to upgrade to the AP setup..... on removing my stock items i could see that i was damaging the stock items so i was happy to replace them and sell them while they were fresh and sellable still, luckily they are in service on a normal powered/driven car now so no doubt will last a long while.

i think SS lines, Uprated pads, and proper fluid, ATE superblue is awesome, i think you will still be able to overheat them but you'll get longer out of them, imo the stock items just need alittle sympathy and you'll be fine, but prolonged track use will KILL them!!

Needless to say i can now abuse my APs much more than stock, probably one of my best mods to this car!!

Beedub you big show off!

I gather from your previous posts that there was a decent weight saving too, despite the AP's bigger size?

As a first bit if TLC orientated towards track work my idea was to dump the standard wheels for forgged 18" (I like the current rubber and so do not want to try and kwel understeer - I don't have the level anyway...yet :evil: ) and combined with a serious brake upgrade seems like a idea to drop unsprung weight.

Forged wheel 3k
AP's 2k? Carb Carbide 5K?

BY the way love the sound of a supercharger on a V8 (old and new XKR). Hows it with a straight 6?

 

[ChawenHalo]

If you're out to put down as fast laptimes as you possibly can then you will cook the stock brakes easily. You will even do this on an upgraded stock system (pads, stainless steel lines and good fluid). If you are tracking the car for fun and are not really giving it 10/10ths then an upgraded system will do just fine.

I've got Axxis ULT pads, Goodridge stainless steel brake lines and Endless RF 650 fluid on mine. I could fade the brakes easily with the stock fluid on very fast mountain runs and on the autocross events i take the car too. I installed the pads as a "stock + a bit more stopping power" solution as soon as i wore out the stock ones and liked them for the price. The fluid i upgraded because i could feel a very spongy pedal after long mountain blasts and at the autocross events and i saw a very big difference, the lines i installed to get a bit more feel when braking heavily, you can't really tell a difference on the road but on the track i can feel an improvement there too.

Basically with the whole lot i'm now very pleased. More confidence to bring down my laptimes and prolonged endurance for my mountain runs which can run at 20+km of sustained acceleration/hard braking.

Doesnt mean i wouldnt install a big brake kit if i had the money lying around somewhere.

Yep I think you're bang on that one It makes sense to do these "upgrades" progressively. Get to enjoy how the car evolves. Must be a fairly resonable set up no? Or is man hours / labour costs ridiculous?

 

[olivierZ]

salut le bordelais!

j'ai testé les EBC jaunes, et elles tiennent 3000 bornes sur routes rapides, depuis je trouve qu'elles chauffent trop vite!

je me tate pour tester des hawk ou des axxis... to be continued!

 

[ga41]

Yep I think you're bang on that one It makes sense to do these "upgrades" progressively. Get to enjoy how the car evolves. Must be a fairly resonable set up no? Or is man hours / labour costs ridiculous?

For my needs it works just fine. I installed the pads myself as it's very easy to do (just be careful of the brake pad sensors! Very fragile!), i was going to do the fluid and brake lines as well but i kept putting it off and then had to take it to a shop and they installed them both because i wanted it done within a single afternoon in time for an autocross event the next day.

The particular fluid i chose is expensive but it held up way, way longer than the stock fluid ever did even when new. The brake lines did provide a noticeable difference but only on the track and the pads have slightly more bite than stock and didnt fade on me. I think an upgrade like this is just fine for someone who is just starting to track their car.

Now i need to replace my rotors though because there's quite a noticeable lip on them....

 

[ChawenHalo]

Halo halo fellow Froggy.

Specialist recommended ferodos 2500 or something.

Shame I was going to go to the Cannes Festival in a few weeks but none of my customers can be arsed to go (typical british non-chalant)

BTW I'm a born Ch'ti (ie/ above " ft tall like lost Bordelais )

 

[ChawenHalo]

Yep I think you're bang on that one It makes sense to do these "upgrades" progressively. Get to enjoy how the car evolves. Must be a fairly resonable set up no? Or is man hours / labour costs ridiculous?

For my needs it works just fine. I installed the pads myself as it's very easy to do (just be careful of the brake pad sensors! Very fragile!), i was going to do the fluid and brake lines as well but i kept putting it off and then had to take it to a shop and they installed them both because i wanted it done within a single afternoon in time for an autocross event the next day.

The particular fluid i chose is expensive but it held up way, way longer than the stock fluid ever did even when new. The brake lines did provide a noticeable difference but only on the track and the pads have slightly more bite than stock and didnt fade on me. I think an upgrade like this is just fine for someone who is just starting to track their car.

Now i need to replace my rotors though because there's quite a noticeable lip on them....

rotors? is that the same as disks? (Call me thikky).

You see, that was my initial worry on this post: by upgrading pipes, fluid and pads, surely this upsets the tolerances engineered and can bo**cks the whole set up by putting added pressure on the disks, they were not designed for?

I can't figure out how these vented disks get so hot so quickly. I canned a Scooby around the track redlining for an entire afternoon and they did not moan once. Saying that it was group N.

I also must have triggered the ESP a fair bit as it was the rear brakes squeeking and my braking is hard sharp and short.

 

[ga41]

Yep I think you're bang on that one It makes sense to do these "upgrades" progressively. Get to enjoy how the car evolves. Must be a fairly resonable set up no? Or is man hours / labour costs ridiculous?

For my needs it works just fine. I installed the pads myself as it's very easy to do (just be careful of the brake pad sensors! Very fragile!), i was going to do the fluid and brake lines as well but i kept putting it off and then had to take it to a shop and they installed them both because i wanted it done within a single afternoon in time for an autocross event the next day.

The particular fluid i chose is expensive but it held up way, way longer than the stock fluid ever did even when new. The brake lines did provide a noticeable difference but only on the track and the pads have slightly more bite than stock and didnt fade on me. I think an upgrade like this is just fine for someone who is just starting to track their car.

Now i need to replace my rotors though because there's quite a noticeable lip on them....

rotors? is that the same as disks? (Call me thikky).

You see, that was my initial worry on this post: by upgrading pipes, fluid and pads, surely this upsets the tolerances engineered and can bo**cks the whole set up by putting added pressure on the disks, they were not designed for?

I can't figure out how these vented disks get so hot so quickly. I canned a Scooby around the track redlining for an entire afternoon and they did not moan once. Saying that it was group N.

I also must have triggered the ESP a fair bit as it was the rear brakes squeeking and my braking is hard sharp and short.

Yes rotors is the same as disks.

Mine are probably still the original disks, so 5 years old and with 47.000 miles on them. I've had the car for only two years so i cant be sure that they are indeed the original disks but in that two years it's done more than 22.000 hard driven miles with the disks it came with. I dont think changing the pads made much if any at all difference in their wear...

 

[ChawenHalo]

Cool. that makes sense. Can we start a specific voting thread on pads? I'm far too junior member for that

 

[olivierZ]

poor returns with ds2500....

 

[Beedub]

yep im known for showing off alittle........lol

Yes the brakes are awesome... and the blower on the straight6, sounds exactly like your car except with whoooooossshhhhh in the back ground and big blow off noises, way to much fun!!

i think for your learning curve he car out the box is perfect...... slowly mod the car to suit you!! thats all i did, its taken a LONG time but its getting to what it should be...

byron

 

[ChawenHalo]

poor returns with ds2500....

Apparently they squeek all the time! the Z gets enough attention in Bordeaux in the midddle of all these Peagot Mazout and Citrons, so I'd rather avoid "squeek" (girlfriend does that enough in the Z )

What about the yellow and green ones? theres a thread on here somewhere.

 

[ChawenHalo]

yep im known for showing off alittle........lol

Yes the brakes are awesome... and the blower on the straight6, sounds exactly like your car except with whoooooossshhhhh in the back ground and big blow off noises, way to much fun!!

i think for your learning curve he car out the box is perfect...... slowly mod the car to suit you!! thats all i did, its taken a LONG time but its getting to what it should be...

byron

Too damn right! I would with even a supercharged coffee grinder

Supercharging is just too 8)

 

[Lower]

You see, that was my initial worry on this post: by upgrading pipes, fluid and pads, surely this upsets the tolerances engineered and can bo**cks the whole set up by putting added pressure on the disks, they were not designed for?

I can't figure out how these vented disks get so hot so quickly. I canned a Scooby around the track redlining for an entire afternoon and they did not moan once. Saying that it was group N.

I also must have triggered the ESP a fair bit as it was the rear brakes squeeking and my braking is hard sharp and short.

The temperature the discs get to is heavily related to the friction coefficient of the pads and specifically the initial bite of the pad. High initial bite pads need lower pedal pressure to achieve the same level of retardation and the discs just don't get as hot.

At a basic physics level that doesn't make sense because you'd think that the kinetic energy (and therefore heat) going into the discs from slowing the car will be the same. However, in reality it does make a huge difference. I did a fair bit of testing on my S2000 on track and went through a variety of pads and disc combinations, all with OEM callipers, brake lines and fluid, using heat paint to track the disc temperature.The vane configuration of the disc also plays a significant parts as the more air the disc draws through it as it rotates the more the disc is cooled by this airflow. The vane configuration also plays a big part in the dimensional stability of the disc when its hot.

Ferrodo DS2500 pads work well and don't fade even when the disc glows red hot, but they can overheat the disc, cause it to crack and can also give adhesion and warping problems. Unfortunately, the pads i ended up with (Dixcel Type Z) aren't available for the Z4. They gave similar performance to OEM from cold but even better performance when hot but most importantly kept the disc temperature down below 550 degrees C even when being hammered.

I don't have the same experience of the Z4 brakes so my opinion will be of less value than those who have already experimented in this area on this car, but i would be experimenting with different pad compounds before i started changing fluid, brake lines, discs and calipers as previous experience has shown you can make big braking improvements without the cost of a big brake kit.

 

[olivierZ]

the weight is too important on the Z4M for the 2500 (test on Monte Carlo roads), textar are better! :lol:

 

[ChawenHalo]

You see, that was my initial worry on this post: by upgrading pipes, fluid and pads, surely this upsets the tolerances engineered and can bo**cks the whole set up by putting added pressure on the disks, they were not designed for?

I can't figure out how these vented disks get so hot so quickly. I canned a Scooby around the track redlining for an entire afternoon and they did not moan once. Saying that it was group N.

I also must have triggered the ESP a fair bit as it was the rear brakes squeeking and my braking is hard sharp and short.

The temperature the discs get to is heavily related to the friction coefficient of the pads and specifically the initial bite of the pad. High initial bite pads need lower pedal pressure to achieve the same level of retardation and the discs just don't get as hot.

At a basic physics level that doesn't make sense because you'd think that the kinetic energy (and therefore heat) going into the discs from slowing the car will be the same. However, in reality it does make a huge difference. I did a fair bit of testing on my S2000 on track and went through a variety of pads and disc combinations, all with OEM callipers, brake lines and fluid, using heat paint to track the disc temperature.The vane configuration of the disc also plays a significant parts as the more air the disc draws through it as it rotates the more the disc is cooled by this airflow. The vane configuration also plays a big part in the dimensional stability of the disc when its hot.

Ferrodo DS2500 pads work well and don't fade even when the disc glows red hot, but they can overheat the disc, cause it to crack and can also give adhesion and warping problems. Unfortunately, the pads i ended up with (Dixcel Type Z) aren't available for the Z4. They gave similar performance to OEM from cold but even better performance when hot but most importantly kept the disc temperature down below 550 degrees C even when being hammered.

I don't have the same experience of the Z4 brakes so my opinion will be of less value than those who have already experimented in this area on this car, but i would be experimenting with different pad compounds before i started changing fluid, brake lines, discs and calipers as previous experience has shown you can make big braking improvements without the cost of a big brake kit.

Good post mate, a fellow geek! What you say makes sense. Its supposed to be the CSL's weakpoint too. The disks are too thin and prone toi crack when over heated. Thats why I'm a little weary of mucking about with components over the OEM.

Anyone else on specific pads please?

 

[ChawenHalo]

the weight is too important on the Z4M for the 2500 (test on Monte Carlo roads), textar are better! :lol:

It is a fairly porkly (as in pig/pork) car, especially when you consider the Cayman which is 1380 kg or something. I recon the M is even worse with a reinforced rear axle, slip diffential etc.

Not to mention all these cote de boeuf and chips I get through

Thanks for the tip Oliviez.