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Discussion Starter · #1 ·
Right , yet again i have frightened myself silly..................I have vowed that it will be the last time. Yet again whilst having a spirited drive i found myself having to stop and being unnable to do so. Pretty typical situation one would encounter on a regular basis. Ambling along a dual carriageway ( warp engine engaged ) and the white van pulls out in front of me ( without looking ). Fortunately for me tha inside lane that he had just vacated was empty so i was able to head in that direction. Why did he pull out .........??
Well your guess is as good as mine. I did have a small word in his ear like.( suggested something along the lines of ripping his head off and depositing something down the neck cavity ).
Thing is , when i needed to stop , i couldnt. The brakes are innadequate.......... anything under 70 MPH they are ok , over that and they dont work . I no longer have confidence that the beast will stop . this is no good. So , my quest here is , what is the best and least expensive way of making sure that the brakes will work. I realize i have to move away from the standard set up as IMHO it is not up to the job.
I want to hear your trials and tribulations in your quest to stop . What works and what doesnt.
To set some parameters , i wish to keep the original wheels and we have to keep the cost sensible.
Thanks in advance ,
Regards,
Nat.



:byebye:
 

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Well there are two decent options.. neither of which are cheap... although one is cheaper than the other.
BREMBO make a 4 wheel BBK set up, all that is needed is spacers for the front wheels....
STOPTECH are now making a 4 wheel BBK that will fit under the stock wheels, they have a set up that needs after market wheels but I guess market forces have made them revisit the design.

Best bet is to visit Dave at Zeckhausen.com

He is the guy who can answer all your questions
 

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Granted that repeated stops from high speeds such as on a road course show up the brakes as not having adequate thermal capacity, but for a situation as described above, the stock brakes on the M5 are perfectly fine. As long as the pads and rotors are in good shape, you should be able to nail the brakes at 150mph and have plenty of stopping power all the way to 0. Something is amiss with your brakes.
 

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The only reason to go with BBK is when you do repeated stops from high speed and you over heat your stock brake too often that it starts to fade. Your situation does not sound like you need a BBK. Do a fluid flush and performance pads first.
 

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The only reason to go with BBK is when you do repeated stops from high speed and you over heat your stock brake too often that it starts to fade. Your situation does not sound like you need a BBK. Do a fluid flush and performance pads first.
I agree, except watch your choice of pad. For panic stop situations, it's hard to beat a stock pad because of its excellent initial bite characteristics. If there is a high degree of speed differential between you and the other vehicle and you are at a high rate of speed, it WILL take you some distance to stop no matter what. It's simple physics. If you braked hard enough to invoke the ABS (you can tell by the heavy pulsations of the brake pedal), you were stopping about as short as you could whether you had stock brakes or aftermarket ones. Some tires do stop better than others, so you might check into that. Changing to big brakes won't necessarily improve stopping distances, as their purpose is to reduce brake fade after repeated stops.
 

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I think AP Racing do something as well as I am thinking about upgrading to these.

You will find more detail on the AP set up if you do a search. A couple of grand needed for this solution.

Pip
 

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Discussion Starter · #8 ·
Thanks for the replies so far. For the record the ABS was not activated.
One of the comments was that the standard set up should work best with OE pads as they have a good initial bite. Well there was no bite at all.The only way i can describe the braking action was almost as if the rears were doing the lion share of the braking. Seems all is not well and i will admit i was doing well in excess of 3 figures. Inspection II was done 5k and no remarks/observations regarding pads/rotors. Fluid was changed at that time.I will have my good friend Phill at Birds take a look and see what he can find . Obviously something amis here. Again as before sub 80 MPH they are fine.
Thanks for all the input.
Regards
Nat.

:D :eek:



Pip said:
I think AP Racing do something as well as I am thinking about upgrading to these.

You will find more detail on the AP set up if you do a search. A couple of grand needed for this solution.

Pip
 

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On track, I've done repeated stops from 120 or 140mph with stock brakes and pads. They have worked quite well with quite high threshold braking force and can activate ABS at high speeds. That simply means that the tires or pavement are the limit not brake force. My only brake mods are adding brake ducts and high temp fluid. Niether changes braking force but help with repeated stops.

There is definitely an issue if you can't get to ABS on clean dry pavement. The pads or rotors could be glazed or its possible the fluid has overheated and is no longer optimal. Does the pedal feel soft?
Have you had the car since new? Do you know for sure the pads are stock? Racing pads don't work well from a cold stop. Does stopping improve after a 2nd or 3rd attempt? I would definitely have a brake expert look into it.
 

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I would definitely have a brake expert look into it.
Yep. Totally agree.
 

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The lightest is brembo but requires spacers which become a weak point, so it's somthing Ive never been in favor of (spacers), even though they have been proven to be farily safe.

You can do all the small crap, lines, pads etc...But its not enough.


BBK are for more than track use in my opinion, though I'll take heat for it...I run um on my other car with only 13" rotors and 4 piston calipers, and love it way more than the 5's brakes. I intend by the end of the year to get the stoptech 4 wheel kit that fits under the stock wheels, For you I say start with the stoptech 4 wheel fronts, thats gonna be the cheapest and best bet to start.
 

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NAT said:
Thanks for the replies so far. For the record the ABS was not activated.
One of the comments was that the standard set up should work best with OE pads as they have a good initial bite. Well there was no bite at all.The only way i can describe the braking action was almost as if the rears were doing the lion share of the braking. Seems all is not well and i will admit i was doing well in excess of 3 figures. Inspection II was done 5k and no remarks/observations regarding pads/rotors. Fluid was changed at that time.I will have my good friend Phill at Birds take a look and see what he can find . Obviously something amis here. Again as before sub 80 MPH they are fine.
Thanks for all the input.
Regards
Nat.

:D :eek:
I would change the pads, rebed them (instructions can be found here -- (http://www.zeckhausen.com/bedding_in_brakes.htm) and see where you are then. What you're describing would be consistent with having certain non-OEM pads, as noted above, and this might not have been noticed or mentioned to you in connection with the Insp. II. OEM and aftermarket pads look alike; you'd be hard-pressed (pun intended) to tell the difference at a casual glance. The performance issues may be less apparent when braking from lower speeds because you're not as intent on slowing down right now.
 

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Discussion Starter · #13 ·
Right i m going back to square one. Ordered this morning , new disks, axxis ultimate pads , braided hoses, and cold air intake brake ducts. Given that these will all take time to come ( pads fron the good old USA ) it will be a while before i get back to you all.
I will report back when done.
Thanks very much 4 all your input.

Regards

Nat.

:D :D





EdP said:
I would change the pads, rebed them (instructions can be found here -- (http://www.zeckhausen.com/bedding_in_brakes.htm) and see where you are then. What you're describing would be consistent with having certain non-OEM pads, as noted above, and this might not have been noticed or mentioned to you in connection with the Insp. II. OEM and aftermarket pads look alike; you'd be hard-pressed (pun intended) to tell the difference at a casual glance. The performance issues may be less apparent when braking from lower speeds because you're not as intent on slowing down right now.
 
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