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Z4m brakes.
Posted: Fri Aug 04, 2017 9:42 am
by Ed Doe
Tom I didn't know that - so does that statement regarding the deployment of leading pistons on 4pot upwards calipers apply to all calipers or just specifically to the Porsche ones?
I've just got hold of a set of the bmw performance 6pots and csl discs to fit to my non-M Coupe, I was intending to leave the rears as they are certainly for the time being - curious as to your experience regarding biasing issues? I wouldn't have thought the bias would be significantly affected.
I certainly found the oe stuff doesn't hold up to track well last time out at Goodwood - the pads are totally shagged now, hence the look for a sensible upgrade!
Z4m brakes.
Posted: Fri Aug 04, 2017 9:45 am
by D4dawg
Sorry spectre
But when I make comments to actually *help*
People I DO NOT NEED that muppets personal attacks
So it's not the first time he's been an anti social tool
And not the last no doubt
So if I get offend and happy to put my money where my mouth is then let him suffer the consequences of his actions, as we even had an inbox conversation regarding another time and he apologised yet no lesson learnt
Yes I may have been a bit hard core
But sometimes to deal with a bully you have to
So perhaps help and keep him in check ?
As yes fishy my mates are
Others own an f1 team
Good friends with sir Stirling and his family and chief designers in certain super car manufacturers and owners of super car manufacturers
People that know me in the real world can verify this
I don't lie nor need to make things up nor do i need to be pretentious and have ever mentioned this before
But they helped me a: buy my brake set up b: make sure it all fitted and c: helped test it all
And at ed no no it doesn't
Look at my link to tests of my rear brakes
https://youtu.be/l1QtvuV1EOM
Z4m brakes.
Posted: Fri Aug 04, 2017 10:31 am
by Fishy Dave
D4dawg wrote: ↑Fri Aug 04, 2017 9:45 am
As yes fishy my mates are
Others own an f1 team
Good friends with sir Stirling and his family and chief designers in certain super car manufacturers and owners of super car manufacturers
People that know me in the real world can verify this
I don't lie nor need to make things up nor do i need to be pretentious and have ever mentioned this before
But they helped me a: buy my brake set up b: make sure it all fitted and c: helped test it all
I wasn't accusing you of fibbing, it's just that I work in Motorsport so was interested.
Z4m brakes.
Posted: Fri Aug 04, 2017 12:14 pm
by D4dawg
Fishy Dave wrote: ↑Fri Aug 04, 2017 10:31 am
D4dawg wrote: ↑Fri Aug 04, 2017 9:45 am
As yes fishy my mates are
Others own an f1 team
Good friends with sir Stirling and his family and chief designers in certain super car manufacturers and owners of super car manufacturers
People that know me in the real world can verify this
I don't lie nor need to make things up nor do i need to be pretentious and have ever mentioned this before
But they helped me a: buy my brake set up b: make sure it all fitted and c: helped test it all
I wasn't accusing you of fibbing, it's just that I work in Motorsport so was interested.
Mate you should know me by now:)
I'm always happy to help always happy to give advice I even send parts free to other members on here and other forms
Just don't need crap from a keyboard warrior so please don't take offence buddy
N yes mate know alot of people in motorsport and car world, it's a very small.world after all as everyone knows and uses same people for parts and supply etc
Z4m brakes.
Posted: Fri Aug 04, 2017 12:16 pm
by TomK
Ed Doe wrote: ↑Fri Aug 04, 2017 9:42 am
Tom I didn't know that - so does that statement regarding the deployment of leading pistons on 4pot upwards calipers apply to all calipers or just specifically to the Porsche ones?
I've just got hold of a set of the bmw performance 6pots and csl discs to fit to my non-M Coupe, I was intending to leave the rears as they are certainly for the time being - curious as to your experience regarding biasing issues? I wouldn't have thought the bias would be significantly affected.
I certainly found the oe stuff doesn't hold up to track well last time out at Goodwood - the pads are totally shagged now, hence the look for a sensible upgrade!
Missed all the fun this morning
Ed, yes essentially the rear boxster calipers used in this application on our cars are mounted on the rear of the hub whereas in a boxster they are mounted on the front. These (and I believe most multi piston) calipers have different sized pistons front to back so that they apply different pressures over the pad, as the leading edge of the pads will tend to bite harder due to the inherent dynamic forces between pad & disc. The slightly smaller piston applies less pressure to the leading edge thus balancing the pressure over the pad.
Having it the wrong way round with the larger piston on the leading edge is probably not going to make a huge difference to braking capability but it will surely lead to uneven wear on pad. Fortunately the solution is very simple, just swap the link tube so that the bleed nipples sit at the top of the caliper. I'm sending my CV off to Red Bull asap
As for bias, there is a fairly simple calculation you can make to see what you're messing with, but no I doubt it's going to be a huge issue for you particularly as the bias in your case will be going towards the front. You could perhaps use a more aggressive pad compound in the rear to compensate if you feel the need.
Z4m brakes.
Posted: Fri Aug 04, 2017 2:15 pm
by Beedub
OP i have an off the shelf AP racing big break kit and apart from the insane replacement parts costs, including the consumables it really offers incredible brake behaviour.. really top notch pedal feel and modulation at the limit, and can take laps and laps of abuse. If it were me id consider a proper tried and tested setup, id always be wary pf something designed for another vehicle, however I'm aware some of these setups do function well also.
i noted on ZPOST that the m4 calipers bolt directly onto our hubs, no machining , no spacers or carriers needed, but id guess the piston size is not compatible with our vehicles.
Z4m brakes.
Posted: Fri Aug 04, 2017 3:26 pm
by adam1985
TomK wrote: ↑Fri Aug 04, 2017 12:16 pm
Ed Doe wrote: ↑Fri Aug 04, 2017 9:42 am
Tom I didn't know that - so does that statement regarding the deployment of leading pistons on 4pot upwards calipers apply to all calipers or just specifically to the Porsche ones?
I've just got hold of a set of the bmw performance 6pots and csl discs to fit to my non-M Coupe, I was intending to leave the rears as they are certainly for the time being - curious as to your experience regarding biasing issues? I wouldn't have thought the bias would be significantly affected.
I certainly found the oe stuff doesn't hold up to track well last time out at Goodwood - the pads are totally shagged now, hence the look for a sensible upgrade!
Missed all the fun this morning
Ed, yes essentially the rear boxster calipers used in this application on our cars are mounted on the rear of the hub whereas in a boxster they are mounted on the front. These (and I believe most multi piston) calipers have different sized pistons front to back so that they apply different pressures over the pad, as the leading edge of the pads will tend to bite harder due to the inherent dynamic forces between pad & disc. The slightly smaller piston applies less pressure to the leading edge thus balancing the pressure over the pad.
Having it the wrong way round with the larger piston on the leading edge is probably not going to make a huge difference to braking capability but it will surely lead to uneven wear on pad. Fortunately the solution is very simple, just swap the link tube so that the bleed nipples sit at the top of the caliper. I'm sending my CV off to Red Bull asap
As for bias, there is a fairly simple calculation you can make to see what you're messing with, but no I doubt it's going to be a huge issue for you particularly as the bias in your case will be going towards the front. You could perhaps use a more aggressive pad compound in the rear to compensate if you feel the need.
From my understanding the brake bias is not fixed and is automatically adjusted by the DSC so would this not compensate for the improved front braking?
Z4m brakes.
Posted: Fri Aug 04, 2017 3:48 pm
by TomK
adam1985 wrote: ↑Fri Aug 04, 2017 3:26 pm
From my understanding the brake bias is not fixed and is automatically adjusted by the DSC so would this not compensate for the improved front braking?
I think (but stand to be corrected) that the DSC module only adjusts bias when it detects a difference in deceleration of the wheels on each axle, i.e when a loss of traction (lock up) occurs. Up until that point the bias is pre set in the ecu to take account of the factory relative braking performance front to rear. If you alter this relationship with an upgraded front brake setup the car will still use the factory set bias up until the point of locking.
Z4m brakes.
Posted: Fri Aug 04, 2017 4:29 pm
by adam1985
TomK wrote: ↑Fri Aug 04, 2017 3:48 pm
I think (but stand to be corrected) that the DSC module only adjusts bias when it detects a difference in deceleration of the wheels on each axle, i.e when a loss of traction (lock up) occurs. Up until that point the bias is pre set in the ecu to take account of the factory relative braking performance front to rear. If you alter this relationship with an upgraded front brake setup the car will still use the factory set bias up until the point of locking.
You could be right, I havent managed to find any documantation about exactly how it works but I was under the impression, particularly from people discussing e46, that it is adjusted all the time to try and avoid lock up and the ABS kicking in. Found this statement on
http://www.unixnerd.demon.co.uk/e46mechanics.html
Electronic Brake Proportioning (which I'm guessing comes out as EBV in German) adjusts the brake bias between the front and rear wheels under computer control. All cars have a bias that sends more braking force to the front wheels than the rear. The reason for this is that weight transfer under deceleration means the front wheels have more load on them and can thus sustain higher braking forces without skidding. It's often the case that the front wheels do two thirds of the work and rears a third, that's why front wheels get covered in brake dust more quickly.
EBV can adjust the front / rear bias to cater for a lightly or heavily loaded vehicle and thus optimise the overall braking effort and reducing the likelihood of the ABS kicking in. You often find a manual adjustable hydraulic bias valve in rally cars.
Z4m brakes.
Posted: Fri Aug 04, 2017 5:17 pm
by Vanne
Beedub wrote: ↑Fri Aug 04, 2017 2:15 pm
OP i have an off the shelf AP racing big break kit and apart from the insane replacement parts costs, including the consumables it really offers incredible brake behaviour.. really top notch pedal feel and modulation at the limit, and can take laps and laps of abuse. If it were me id consider a proper tried and tested setup, id always be wary pf something designed for another vehicle, however I'm aware some of these setups do function well also.
i noted on ZPOST that the m4 calipers bolt directly onto our hubs, no machining , no spacers or carriers needed, but id guess the piston size is not compatible with our vehicles.
Gday Byron, I know it all the heat it may have gotten lost on everyone, I am not looking for a BBK, already have the Brembo GT's, do that's fine
I was just wondering what to do with my oem setup, and wondered if they would be a direct bolt on for non M zeds.. which isn't the case.thatnks heaps guys for all the inputs and advise.
Sorted.
Cheers. Byron, thx for the Mini review mate? Any issues? What pads are you running?
What pads are all you guys with BBK's running?
Z4m brakes.
Posted: Fri Aug 04, 2017 5:21 pm
by MrPT
Ed Doe wrote: ↑Fri Aug 04, 2017 9:42 am
I've just got hold of a set of the bmw performance 6pots and csl discs to fit to my non-M Coupe, I was intending to leave the rears as they are certainly for the time being - curious as to your experience regarding biasing issues? I wouldn't have thought the bias would be significantly affected.
The calipers are a good match for the non-M. Less than 5% increase in piston area vs stock. But you're also increasing the size of the front rotor by 20mm, so while it will be safe, you're not necessarily going to get the best total braking performance, front plus rear, and you might get the feeling of the car standing on its nose a bit under heavy braking (I haven't actually experienced this myself, but since you track your car you should be able to suss everything out quite quickly).
Z4m brakes.
Posted: Fri Aug 04, 2017 6:41 pm
by Beedub
Vanne wrote: ↑Fri Aug 04, 2017 5:17 pm
Beedub wrote: ↑Fri Aug 04, 2017 2:15 pm
OP i have an off the shelf AP racing big break kit and apart from the insane replacement parts costs, including the consumables it really offers incredible brake behaviour.. really top notch pedal feel and modulation at the limit, and can take laps and laps of abuse. If it were me id consider a proper tried and tested setup, id always be wary pf something designed for another vehicle, however I'm aware some of these setups do function well also.
i noted on ZPOST that the m4 calipers bolt directly onto our hubs, no machining , no spacers or carriers needed, but id guess the piston size is not compatible with our vehicles.
Gday Byron, I know it all the heat it may have gotten lost on everyone, I am not looking for a BBK, already have the Brembo GT's, do that's fine
I was just wondering what to do with my oem setup, and wondered if they would be a direct bolt on for non M zeds.. which isn't the case.thatnks heaps guys for all the inputs and advise.
Sorted.
Cheers. Byron, thx for the Mini review mate? Any issues? What pads are you running?
What pads are all you guys with BBK's running?
arhhh yes.... I've definitely got lost somewhere, i run APF404s for roaduse and pagids 29s for the track.... a set of pagids for these APs is like 700 quid plus !!!!
Z4m brakes.
Posted: Fri Aug 04, 2017 10:45 pm
by TomK
Vanne wrote: ↑Fri Aug 04, 2017 5:17 pm
I was just wondering what to do with my oem setup, and wondered if they would be a direct bolt on for non M zeds.. which isn't the case.thatnks heaps guys for all the inputs and advise.
Sorry if the initial question got lost somewhere Vanne!
If it were me I would be selling the front caliper carriers and the rear calipers themselves to the m3 boys. Both are specific to the CSL upgrade a few do. The front calipers are exactly the same as a boggo m3, so not worth a lot. It's the front carriers, front discs and rear calipers (slightly increased piston size to work with the bigger front disc) that make up the difference between standard m3 and m3 csl/z4m.
The front carriers go for a fair chunk of money, £200 or so iirc
In answer to your other question, I use pagid rs-29 like beedub, an awesome pad if expensive. How you getting on with Brembo gt's? Taken it on track with them yet? What pads do you run in those?
Z4m brakes.
Posted: Fri Aug 04, 2017 11:19 pm
by D4dawg
So expert
Explain bleed nipples being at *top* of caliper and linkage at the base
As you'd have to be a kind of special to invert a caliper
As clearly shown here of passenger rear
But oh your an expert knowing which side of strut the springs are an all
Humble pie time
Z4m brakes.
Posted: Fri Aug 04, 2017 11:31 pm
by TomK
D4dawg wrote: ↑Sun Apr 30, 2017 7:33 pm
MrPT wrote: ↑Sun Apr 30, 2017 7:16 pm
They look insane! Nice to see brembo logos on actual brembos for once too.
You remembered to swop the rear caliper bridge pipes/bleed valves round, right? Ok, just checking...
Haha hear you met Stu today;)
I had them painted and then remembered!
But size of pistons it's not an issue as only 2mm in it
Otherwise I'd have taken off to sort;)
And many thanks buddy
Not going for the plastic over brembo ebay specials;)