retrofit brake kit bmw performance

[GTAStradale]

I am also starting a thought process that this is the way to go. So any advice or experience would be appreciated!

The only thing I know about these brakes - I met a guy on a racetrack last year in Austria who had them fitted on his CSL. It was his first track day with these brakes, but I remember he was not impressed at all. I am trying to get hold of him nowadays to see if he can share some more info with me (e.g. which pads did he have on). I will keep you guys posted...

[shimmy]

In what way does the AP kit feature better cooling?

Bigger discs, better Disc vanes and venting. Otherwise why would the AP not overheat like the BmW OeM.

[_Nathan_]

Better vanes and venting? Based on what matey?

Difference is the calipers rather than the disks in my opinion.

[_Nathan_]

What disks did matt use with his Porsche brakes?

[mattCSLnut]

Better vanes and venting? Based on what matey?

Difference is the calipers rather than the disks in my opinion.

I have to agree :smt045 ...

[mattCSLnut]

What disks did matt use with his Porsche brakes?

... just don't drag me into this battle :gayfight: will Ya

[shimmy]

Better vanes and venting? Based on what matey?

Difference is the calipers rather than the disks in my opinion.

So why do BmW overheat nd AP not overheat in he same circumstances?

[_Nathan_]

What type of fade did you get with the oem setup? Pad or fluid? For me it was fluid, bigger calipers made of different material can dissipate heat better / faster than the oem ones so prevent the fluid boiling, I also suspect that sliding v non sliding means heat is less localised in the opposing piston calipers?

[shimmy]

What type of fade did you get with the oem setup? Pad or fluid? For me it was fluid, bigger calipers made of different material can dissipate heat better / faster than the oem ones so prevent the fluid boiling, I also suspect that sliding v non sliding means heat is less localised in the opposing piston calipers?

Surely the heat starts in the disc, and the venting of the disc is bigger and better IMHO so temps will be less, and less transferred to the calliper and fluid. With OeM I had both lad fade and fluid boiling. Only on very rare cases I have had a soft pedal with AP set up

[_Nathan_]

The csl disks are vented though, what makes you say the AP venting is better? the ap disks have 6mm bigger radius from memory which as a percentage isn't huge.

No proof to back it up but I strongly suspect that ap calipers on CSL disks would be fine.

On the pad fade thing, I wonder how much of that is the smaller oem pad having less heat capacity?

Perhaps the PF guy can add something here?

[alexk]

The csl disks are vented though, what makes you say the AP venting is better? the ap disks have 6mm bigger radius from memory which as a percentage isn't huge.

No proof to back it up but I strongly suspect that ap calipers on CSL disks would be fine.

On the pad fade thing, I wonder how much of that is the smaller oem pad having less heat capacity?

Perhaps the PF guy can add something here?

The AP discs are also 4mm thicker (32 vs. 28) so the vents are 'bigger'.
Plus, the more metal you have, the more heat capacity you have.
I think the discs are making a difference, but I agree that the big difference comes from the calipers.

[shimmy]

The csl disks are vented though, what makes you say the AP venting is better? the ap disks have 6mm bigger radius from memory which as a percentage isn't huge.

?

6% at the outside edge so increase in vanes is pi r sq so disproportionate to the original area, shape of venting seems more directional to me at first glance, like it drags air in and are arced(not sure if inside M discs are similar but they dont look it)

im guessing that to decreaseheat build up, stopping it in the disc by increased area/mass and improved venting is much more efficient than trying to disipate it out of callipers once heat already there, but thats as you say just my guess.

All that and 4mm wider vanes



Where is FUchs when you need the old Swede!

[_Nathan_]

Is the friction surface of the AP disks thicker or just a bigger gap in between the 2 surfaces?

Will have a look at a CSL disk at some point as I'm just going on memory but pretty sure they also have directional vanes to suck air in at the centre and expel it at the outer edge.

My brother in law did his engineering uni thesis on performance braking systems and used one of my old CSL disks as part of it, will call him later :thumbs:

[shimmy]

My brother in law did his engineering uni thesis on performance braking systems and used one of my old CSL disks as part of it, will call him later :thumbs:

Calling in the big boys now..........:hahaha:

I'll want to see his credentials :clown:

[_Nathan_]

Another attempt to recruit in to your man train?

He studied at Cranfield and got a good degree from there, currently working in aerospace, he is cleverer than us