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The track and brakes

Discussion in 'DIY (Do-It-Yourself)' started by az3579, Jul 7, 2008.

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    az3579

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    I've got a Driver's School coming up in August and want to get myself a set of dedicated brake pads for use on the track. I probably won't get track pads just yet, but maybe something like Hawk Street pads or something I can use without fear of having to buy new pads every month. Question is: do I have to replace the rear pads as well or can I get away with just swapping the front pads for the track?
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    MGarrison

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    For your first track event, Axxis/PBR Metalmasters front and rear would probably be just fine. I would recommend getting them on the car now/soon, so you'll have them well bedded-in by the event. If your rear pads are mostly new, they would probably be fine. It's never a bad idea to have an extra set of front and rear pads on hand for a driver's school in case you need them. Much better than having to scrub track sessions because you didn't bring extra pads. If your school is 1 day instead of 2, a new set of pads should last through the day just fine.

    ATE Super-Blue brake fluid, and flush the fluid shortly before the event. If brake fluid hasn't been flushed in a couple of years, good idea to bleed new fluid through the clutch slave as well. If your clutch pedal sticks to the floor after the fluid flush, you have to remove the clutch slave from the transmission, and reinstall it, to get the pedal back up. Consider stainless steel brake lines for an upgrade, will improve your pedal feel (the stock rubber lines swell after getting hot from track driving, and make for a spongier pedal). You may find at this point in the car's life, the metal brake lines may be suffering some rust corrosion and need replacing - check that out carefully before flushing the brake fluid.

    Metalmasters can fade a bit when pushed really hard (as all pads can, really), but they hang in there well, and will come back with a couple of quick pumps of the brake pedal if you happen to overheat them.
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    az3579

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    This would be my second event. I am trying to do something I really shouldn't, which is try to cut some spending corners, and I know I'm going to automotive hell for that. Problem is, money's tight for someone making crap money on a fulltime job. :)



    But, pads aren't that expensive. I don't know how I could explain this, but I will try.
    My pads were replaced about a year before my first track event, which was in April. They had a perfectly firm, almost no travel feel. After the event, I felt I had to push quite a bit for them to grab, and now it just feels like I don't know how to brake properly because I was (and still am) used to the brand new 100% brake feeling that I still had before I went. Now I'm on the brake for a good few seconds (I apply slowly) and suddenly the brake grabs during normal street driving, which makes it seem like I don't know how to drive properly, and it's embarassing.


    So, what I want to do is get myself a dedicated set. I don't know how much pad life is left on my rear axle because I haven't bothered to check, but I'm going to buy another set regardless. Based on what you said about being fine if they're new, I'm probably going to buy all 4 because I've had them for quite a while.



    Me being cheap and all, I'm worried about the rotors though. We never replaced those and I don't know when the previous owner replaced them. I have no records about rotors from the papers he gave me. I know the brake balance is set more towards the front, but with the smaller brake balance on the rear, is it okay to skimp on buying rotors for the rears? I figure they aren't used as much. Correct?
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    steven s

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    Replace rotors when you need them.
    If you have track pads up front, you are going to go through rear street pads quick.

    Having the same track pads on the front and rear are not always the solution either.
    I run Carbotech XP11 on the front and XP8 on the rear. One time <in band camp> I had XP8 up front and Ultimate Axxis on the rear. I burned through the rears in a weekend.

    Cut corners on going out to dinner. Don't cut corners on brakes.
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    az3579

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    It must be the Bimmer-OCD in me, the same one that sets all the ventilation controls to the middle setting and the seats to the same exact reclining and sliding position, that can't grasp the idea of having different pads on front and rear. What would be wrong with getting the same pad for all four? Will I have to replace my fronts twice for every time I replace the rears? How does it work exactly?

    I'm trying to figure out when I have to get new pads according to the number of times I go to the track. I don't know how it is in other chapters, but at Lime Rock, we go out in sessions and so the number of laps I could do is probably going to be very close to the last time, so if I do 20 laps in one DS, then I will probably do about 19-21 in the next one.


    I'm still trying to understand how much faster the fronts wear as opposed to the rears.

    As for rotors, it doesn't exactly work that way for me ("replace rotors when you need them"), partly because I don't feel like replacing rotors in the middle of the day when I'm there just because they still had a bit of fight left earlier. Also, I can't just replace one rotor and leave the rest; the way I think will have me replace all of them if I do any replacing at all.


    I just want to get an idea how long these parts will last me so I can say "okay I've been to this many events with this set, it's time to replace". I also thought about the skimping and found myself wanting to get 4 of pads and rotors so that nothing's left out.





    As far as what equipment I will buy, I was looking around Tire Rack and found some potential products. I don't know what pads I should get, but I was going to get Hawk Street pads because I hear they are good. I'm avoiding anything that squeals, on track or off, hot or cold, because it will drive me nuts. Any others worth getting? For rotors, I was thinking of getting the PowerSlot rotors that are slotted but not drilled. They are pretty hefty in price though; I think they were like $60+ a piece. Four of those plus the pads really adds up. Or, maybe I should just get plain vented rotors for about $30-40 a piece and get standard brake pads that will last me maybe a few hours... aaah I hate choices, especially if I don't know anything about them. :confused:
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    steven s

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    Track pads squeal.
    On my car using the same track brake pads F/R gave me too much brake in the rear.
    I found street pads on the rear wore very quickly when I ran track pads up front.
    Rotors don't just go unless they crack or have pad deposits.
    Replace them in front or rear sets. You do not need to replace all four, unless they are worn below spec.

    Many things effect how fast pads wear.
    Obviously braking technique and brake zones. Also how they cool between braking.

    Slotted rotors look cool. It's questionable whether they make a difference.
    These are my experiences. YMMV.

    Did you ever mention what car you have?
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    az3579

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    Thought my avatar explained it all... sorry. :)
    '87 325e
    ^ I assume by '87 they all had disc brakes all around, right?


    Anyway, I'm trying to avoid track-only pads because they are a lot more expensive. The price might be justified though if they last over twice as long on the track than regular pads. How did the Carbotech combo last? Worth the price (what was the price)?


    I've always bought my pads at the local auto parts store, so I know nothing about performance pads, unfortunately. The only site I've actually look at for pads so far was Tire Rack and their selection is either small or there aren't many choices for my car. Anything not on there that's highly recommended for front or rear?



    So if the stock pads don't last long in the rear with track pads up front, what can be done? Different model of pads for front and rear?


    All of these depends on whether it's actually worth it to buy track pads in the first place. If it doesn't last much longer than stock pads, then I'd rather get OE pads for half the price and replace them every track day, but if the track pads will last me a few track days then I'd rather get those. Anyone have any durability reports of how long certain pads have lasted them?

    Jeron guest

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    Buy a deep throat micrometer for $30 to measure your rotors and don't replace them until they hit min spec.

    Use plain blank rotors.

    If you are looking for dedicated pads that you can drive to the track but don't plan to drive around town full time on then I recommend EBC Yellow or Hawk HP+.

    Jeron guest

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    Stock pads wont last long in the rear with track up front because of several factors. The solution is get the same pads front and rear.

    Dont mess with different pads front and rear that is a solution for a problem you haven't encountered yet and wont for a while.
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    Bimmerdan

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    A couple other things that come into play...

    What tires are you going to be running at the school? If you have really sticky R-compound tires, you should have more brakes (track pads) to go with them. If you are running some fairly hard street tires, you could probably get away with some good, high performance street pads. When I run my street tires on the M3, I use Axxis Ultimates front and rear and they hold up fine for the entire day. The track I run at (TWS) has a lot of straights that allow the pads to cool so that certainly helps and I try to stay on the brakes for as short a period of time as possible. Like Steven said, your braking technique has a lot to do with it.

    Also, how many track events do you plan on doing through the course of a year? If it's just 1 or 2, I would think street pads are going to be OK for you. If you plan on doing 6 or 7, invest in track pads.

    Like Jeron and Steven said, use blank rotors. There is no need for slotted rotors.
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    az3579

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    I do have the R-comps and I will probably use them seeing as one of my street tires has a nail in it that's really slowly releasing pressure and don't feel like spitting out $50 for a new tire. Besides, that would be uneven; if I buy tires, all fours must be done!



    Anyway, I don't know how many I will attend in a year. This is only my second event (in a row :D) and I sign up if I can afford to. Of course for a day like this, I tend to "make" myself be able to afford it, but that's another story.

    From what I gather, I shouldn't worry much about rotors. They have no issues as it is and for one day they can surely take the beating, so I won't be buying those.


    I guess my choice will be Hawk HPS street performance pads all around. They are about $25-30 cheaper than the HP+ pads plus they can be used on the street. I'm looking at the rating on TR and see that it has competant stopping power plus lower noise and less dust than the HP+ pads. It's a good compromise for the price.
    The plain vented rotors it will be as well. Thanks a lot for the advice, all. :)

    Jeron guest

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    Hawk HPS are great street pads, low dust, low noise. HP+ are noisy track pads. The HPS will be fine for a new student, try not to overheat them. I would not recommend R-comps for a new student.
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    az3579

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    Well I got them for later use when I'm ready to use them, but now I have to use them seeing as there's a nail in my tire and it's releasing pressure. I find it almost flat every weekend. Besides, my tires are just a pinch above the minimum tread limit that my chapter sets. If it doesn't meet that limit, they won't let it through, so I'm kind of stuck with the R's. Can't allow $250+ on four new tires at the moment.
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    Bimmerdan

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    You need to be aware that R-comps behave very differently than street tires. They have a much higher level of traction until they reach their limit...then they go away...quickly! Street tires are much more forgiving and you can learn a lot more on them.

    Be sure to tell your instructor it's only your second school and you're running R-comps for the first time! Some chapters don't even allow R-comps in the green group...make sure yours does before you get there!
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    az3579

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    I completely agree. I don't want to use the R-comps, which is why I'm trying to get my right front tire "repaired" so it keeps air pressure and is useable on the track. If my tires get passed, then they will be perfect for this one track day and then some so I have time to order new tires. I was thinking of ordering a set of summer performance tires and putting those on my K1's (that currently have the R-comps) so I could use those tires until I have reached the traction limit and need something better.




    Will the R's be okay if I store them for a year?
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    Bimmerdan

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    I think you have a good plan here.

    Be sure they repair it correctly (take it off the rim and repair it from the inside). Would you be able to put that tire on the rear or do you have a staggered setup? The rear tires normally take less of a beating and I would feel more comfortable having a repaired tire on the back as opposed to the front...but that's just me. :)


    Are you going to be able to keep them indoors? Tires will last a good long time if you keep them out of the hot, cold and especially the sun! If you can put them in the house and cover them, they will perfectly fine. (A grill cover designed for a round Weber bar-b-q grill makes the perfect cover for a stack of four tires and you can usually find them really cheap!! I got two of them at Big Lots for $5 and they work perfect!!)
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    az3579

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    Well, I got the tire "repaired" today and it consisted of that beef-jerky looking stuff they stuff in the hole to keep the pressure it. It was only a nail; would it really require taking the tire off the rim and that whole lot? It seems like overkill...


    Besides, even before they stuffed it, I still took quite a few harder turns with the tire the way it was without any noticeable loss of air pressure. I had to add air to it about every weekend. Surely it would be okay for a day if I add air to it midday?


    I don't have a staggered setup and wouldn't have an issue rotating my tires. They are all wearing evenly, believe it or not; I can't detect any more wear on the fronts than the rears. They all have about 4- to 5/32" left. Hopefully I can restrain myself from taking too many corners so I could still use em'... I'll ask the shopt that does my pre-tech to see if it would be okay to just put that tire in the rear. They should know, they're a motorsports shop.

    Jeron guest

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    The best tire repair is a plug/patch that is installed with the tire off the rim. It is a patch with a plug coming out of the center of it and it is inserted into the tire from the inside. Discount tire uses them and will usually repair a tire for free.

    If the tire has not be abused, driven with little or no air, then catastrophic tire failure is rare. With the plug only the main risk is the plug dislodging and releasing the air a a fairly fast rate which you will notice quickly on the track.
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    az3579

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    Well, I had my tire from the previous set plugged up the same way as I just had this morning (strangely the same tire) and they were fine under cornering.

    Jeron, what do you think of Dan's suggestion to rotate the tires to have that tire on the rear? Do you think it would suffice to leave it the way they plugged it this morning and have it perform less work in the rear? It hasn't leaked any air since...

    Jeron guest

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    I would put it in the rear. The fear isn't loosing some air, the fear is having it blow out.

    You may want to check your DE rules, if any, concerning repaired tires.

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