When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
I've got a couple of track days coming up, last time I went to this track, I had stock brakes and I boiled the fluid leaving me to deal with a spongy pedal the rest of the day. I need a fluid flush anyways, but I'm torn between going with something like motul 600 or a DOT 5.1 fluid or if I should stick with DOT 4. My other concern is that the car is my daily driver and I'd like to go at least a year (preferably 2) without doing another brake flush. Will motul last that long? or will it soak up too much moisture and suck after a couple of months?
I'm also going to install a set of EBC yellow pads, so hopefully that will help too.
Motul RBF600 is a great fluid for the track. RBF660 can be tempting because it's that little bit better, but the wet boiling point is actually lower than RBF600 so you will need to replace it more often (recommended is 6 months). I would stick with DOT 4 since DOT 5.1 is easy to confuse with DOT 5, which should never be mixed with DOT 4 or 5.1. The 4/5 doesn't mean as much if you're buying premium fluids anyway.
If you're on more of a budget or don't want to worry about flushing every year, I know a lot of race cars that use ATE Type 200, which is cheaper than Motul and very well regarded among track/racing people.
Hmm, I hadn't thought about ATE typ 200, but that might be what I end up going with. I've used it before, back when it was blue. I'm curious why you say the wet boiling point between motul 660 and 600 is different. According to their website, they both have the same wet boiling point of 399º F, though I know mfg specs and real world testing don't always line up.
My only quandry left, is if I'll notice the difference between the ATE's boiling point of 536º F and Motul's boiling point of 600º F, and if Motul will absorb enough water in the 6-8 weeks between when I put it in and my track time to lower the boiling point to Ate. Oh decisions decisions, I may just have to roll the dice and see what happens.
Unless you have some additional cooling, if you boiled the fluid before neither one of those is going to give you any real added protection.
Change braking style to accommodate the fluid or take steps to add cooling.
And it's a real good idea to change the fluid more often if you do multiple track days.
Yeah, I've contemplated adding brake ducts, but I do so few track days these days that it's hard to justify the expense. I think two things contributed to me boiling the fluid last time. One was that the fluid was old then. Two was I drove the car like I drove my race car; Wait til the last possible moment to brake as hard as possible. After I boiled the fluid in the first session, I realized that my street car isn't a race car and moved my braking points back a bit and did a little coasting at the end of the straights. I might still end up boiling the fluid this time, but I want to give myself every opportunity to prevent it.
What pads are you using @Racingguy04? My R53 endurance race car spends 8+ hours on track at race pace and has never boiled fluid, without any additional brake cooling. The race pads (Raybestos ST43) will fade before the fluid boils (tested while breaking in the pads).
My First thought was ... You use way to much brake .... But really ... before tracking my cars, First off I have swapped over all the OEM rubber flex lines for quality stainless braided lines all around the cars. I ALWAYS replace the brakes and flush and fill the the system with DOT 4 (won't discuss brands because that is a Coke Pepsi argument).
You can get complete brake service kits for as low as $300.00 and that is all in all inexpensive for having good anchors for the track, and the remnants of them will last for your daily driving until the next time you track your car when you do it all over again.
And for a small investment You may want to think about a front brake cooling kit like ...
hahaha, I have been eying that brake duct kit for years! but I just haven't had the cash for it. The track I'm at, the longest straight is a bit over a half mile. I'm usually doing about 110 at the end of the straight and brake to about 40mph for the turn (turn 4) and there's also a pretty hard braking zone that you have to go all the way down to first gear for a turn. (turn 8). Turns 7,10, 11, and 1 are moderate braking, and I think that's where i'm building more heat than the big stops, but my scary moment was when I got on the brakes hard at turn 4 and the pedal went to the floor. I definitely changed my brake management after scaring myself going into turn 4, almost all of my track experience has been in racing Karts and formlua fords and I never had any kind of brake fade or management issues in those, but the brakes are way over engineered for the weight of the car vs what a street car has.
I also made the mistake last time of going to the track with oem pads and fluid of an unknown age (I had bought the car used only a few months before taking it to the track) so I figure I'll do my best to fix those issues, improve my braking technique, and then see if I still need cooling for the brakes. Thanks for the advice.
After saying to myself "go big or go home" I decided to go with motul 600, and I got myself a motive pressure bleeder. This way I don't have to drag the wife out to the garage for 30 minutes of "down, ok, up" total for 1 liter of motul and the pressure bleeder was $90, seeing as the local garage quoted me $138 for a single flush, I figure this will be right up there with the financial decision to buy my own clippers and do my own hair cuts.
I'm curious to see how the brakes perform with track oriented pads and fresh, high temp brake fluid. Hopefully it keeps me out of the grass. And I figure with the pressure bleeder, it will be much more convenient to bleed the brakes as needed. Thanks for all the input.
FWIW, I bleed my brakes within a 2-3 day window of my next event. I've never lost my brakes, even in hot, humid, NC weather. The trick is to use your brakes over the shortest distance possible in order to slow the car enough to make the turn. You don't tell us what car but I'll assume an R53. Take your fog lamps out, get a couple of plastic laundry soap caps and cut the tops out. Use a 2 inch hole saw and cut holes in your front wheel well liners right behind the fog lamp holes. Get some 2 inch high temp hose (the stuff with spiral wire in it). Stick the caps thru the holes and attach the hose to the caps with hose clamps. Allow the hose to stick through the wheel well liners but cut to length so as to not rub on your tires. It's a cheap but effective way to get air to your calipers.
Yup, R53 with a few basic mods, but mostly stock (I oughta put that in my signature...) but you've sparked a thought in me about bleeding right before the track day, especially since I can do it myself. Do you think 2 months vs 2 days would make a noticeable difference in the boiling point of the fluid?
I like the cheap brake duct idea, but i hate cutting holes in things, especially since right now the car is primarily my daily driver. Do you think taking off the dust shields would make any difference in the cooling?
Depending on where you live, two months vs. two days is HUGE! Brake fluid is hygroscopic. It soaks up water like a sponge. If you live in the desert, no biggie. But if you live in a humid environment, it's a big factor. Yes, take off your front brake shields. Please bear in mind, cutting a 2-inch hole in your wheel well liner is not destroying your car nor will it have any bearing on you getting to and from work. Having your brakes fail while on track might destroy your car. Which is more important to you?
