Brake Fluid Specifications

[mfanatic325]

What's up, my fellow track junkies? Just thought I'd share what I stumbled across on M3forum. It's a nice database of some fluids that ya'll may be interested in comparing
I'm currently only using ATE Super Blue, since it seems to be good bang for the buck. Someone please let me know if I'm missing out on some good "juice"

http://www.m3forum.net/m3forum/showthread.php?t=424698

On a side note: does anyone know if higher-performing fluids need to be swapped out more often? Conventional wisdom (okay, more like an educated guess lol) is that with higher-performing fluid, I could probably change slightly less than normal? With all else equal of course.

[gmd2003]

I have been using Castrol SRF , best dry and wet boiling point, and is good for a year . It is expensive but worth it, gives great pedal feel that doesn't change .You can't boil it period, and I've tried with PFC 08 pads and rotor temps of 1000 degrees.

[007MCoupe]

I recently changed to ATE Super Blue as well, but have only 1 track session with it so far.

[Kgolf31]

Super blue here.

The cheapest fluid you can get that wont boil IMO.

There are more safer alternatives, but they do cost alot more

[ga41]

I use Motul RBF 660. With the Stoptech BBK i've got i don't experience a soft brake pedal even after a 20-25min track session. I used to run Endless RF 650 which was a bit better (on stock brakes) but it's quite a bit more expensive. The Motul is the best bang/buck for my use at the moment.

Also, when you boil your brake fluid, then you will gradually lower it's boiling point and as time goes by moisture will eventually contaminate it through seals, caps etc and lower it even more. That's where a high wet boiling point helps more. The Castrol SRF has the highest available wet boiling point i believe, though not the dry, and so will probably "last" more before replacements.

You might say that using a cheaper fluid with a lower wet boiling point and more frequent bleeds will end up costing the same or even less. Depends on your use and how often you're willing to bleed your brakes.

If i have any of these wrong, feel free to correct me.

[gmd2003]

The SRF is 590 dry / 518 wet , and is designed for prolonged use, I.e designed not to absorb water . Brake fluid absorbs moisture over time so Motul 600 for instance is no where near a 600 degree boiling point after a month( it's 410) it's also only 593 dry ( false advertising lol) . I would rather pay more and know my fluid is good for a year. If you don't mind replacing the fluid frequently then it's fine to use other things. Super blue is good , but the pedal feel is much more consistent with SRF than Motul 600 and super blue after a couple months . I've used all three .

[Barryb97]

Great information. I've been using super blue also. We'll see how things hold up this track season. Maybe it's time to try some SRF.

[mfanatic325]

Originally Posted by gmd2003

I have been using Castrol SRF , best dry and wet boiling point, and is good for a year . It is expensive but worth it, gives great pedal feel that doesn't change .You can't boil it period, and I've tried with PFC 08 pads and rotor temps of 1000 degrees.

How much do the Castrol SRF run those of you that use it? Where do you buy from? Just curious for future reference, thanks.

[jmillet]

Originally Posted by Barryb97

Great information. I've been using super blue also. We'll see how things hold up this track season. Maybe it's time to try some SRF.

Castrol SRF at over $50 per liter is way more brake fluid than we need for high performance driving school events. If you're using Ate TYP200 or Super Blue with high temperature brake pads such as PF-06 or PF-01 and you're getting a soft brake pedal during a 30 minute track session then you need to examine your braking technique before spending money on SRF.

[a_riddler]

Alternate between ATE super blue and TYP200. Makes fluid changes easy.

[gmd2003]

Originally Posted by jmillet

Castrol SRF at over $50 per liter is way more brake fluid than we need for high performance driving school events. If you're using Ate TYP200 or Super Blue with high temperature brake pads such as PF-06 or PF-01 and you're getting a soft brake pedal during a 30 minute track session then you need to examine your braking technique before spending money on SRF.

In a 25 minute session in an advanced group with a supercharged Z4M on R-comps its not too much fluid lol. Everybody is different but yes I wanted a more reliable fluid for going at 9/10ths, just giving my real world feedback since I have 8,000 track miles on my Z4M. One of my local tracks CMP is notoriously bad on brakes though, Ive seen a GT500 mustang in the sand pits with its brakes on fire .... , brakes when your stopping from 150 are not the things to save money on IMHO.

[gmd2003]

Originally Posted by mfanatic325

How much do the Castrol SRF run those of you that use it? Where do you buy from? Just curious for future reference, thanks.

Its available from Turner motorsports in a liter bottle for 72 dollars.

[abashoe]

I believe some fluids are more hydroscopic (sp?) than others; meaning more prone to absorbing moisture in the air and therefore lowering their boiling points over time.

I do not know which ones are more/less hydroscopic.

I alternate ATE super blue and type 200. I hear they dont absorb as much moisture, but thats just what i read on the forums.

[O-cha]

Originally Posted by jmillet

Castrol SRF at over $50 per liter is way more brake fluid than we need for high performance driving school events. If you're using Ate TYP200 or Super Blue with high temperature brake pads such as PF-06 or PF-01 and you're getting a soft brake pedal during a 30 minute track session then you need to examine your braking technique before spending money on SRF.

Not everyone uses street tires, there really is a huge difference in strain on the brake system between the two.

However, even with Rcomps I don't get a soft pedal with motul, it's the pads that get too hot first, and that's 1800 degree pads, so I do agree that the fluid should be fine if it's fresh.

[seank]

Originally Posted by mfanatic325

What's up, my fellow track junkies? Just thought I'd share what I stumbled across on M3forum. It's a nice database of some fluids that ya'll may be interested in comparing
I'm currently only using ATE Super Blue, since it seems to be good bang for the buck. Someone please let me know if I'm missing out on some good "juice"

http://www.m3forum.net/m3forum/showthread.php?t=424698

On a side note: does anyone know if higher-performing fluids need to be swapped out more often? Conventional wisdom (okay, more like an educated guess lol) is that with higher-performing fluid, I could probably change slightly less than normal? With all else equal of course.

It is my understanding to change out the blue once a year, since it seems to thicken up with heavy track use.

[jmillet]

Originally Posted by gmd2003

In a 25 minute session in an advanced group with a supercharged Z4M on R-comps its not too much fluid lol. Everybody is different but yes I wanted a more reliable fluid for going at 9/10ths, just giving my real world feedback since I have 8,000 track miles on my Z4M. One of my local tracks CMP is notoriously bad on brakes though, Ive seen a GT500 mustang in the sand pits with its brakes on fire .... , brakes when your stopping from 150 are not the things to save money on IMHO.

I'm running R -888 tires, PF-06 pads on stock calipers/rotors in Group A and instructing at a variety of road course venues such as Pacific Raceways, The Ridge Motorsports Park, http://www.ridgemotorsportspark.com/
Spokane Raceway Park http://www.spokaneracewaypark.com/
Portland International Raceway, and Oregon Raceway Park http://oregonraceway.com/
I'm not supercharged and I don't drive 9/10ths at a driving school; I save that for racing. BTW we don't use SRF in our race cars either. Ate and Motul with frequent flushes has never let us down
Of course if SRF makes you feel more confident at 9/10ths then by all means go for it.
Keep in mind that if you're driving fast on a track, even in a school environment, it's not a matter of if something bad will happen; it's a matter of when. And it's seldom if ever brake fluid to blame; it's operator error

[gmd2003]

Originally Posted by jmillet

I'm running R -888 tires, PF-06 pads on stock calipers/rotors in Group A and instructing at a variety of road course venues such as Pacific Raceways, The Ridge Motorsports Park, http://www.ridgemotorsportspark.com/
Spokane Raceway Park http://www.spokaneracewaypark.com/
Portland International Raceway, and Oregon Raceway Park http://oregonraceway.com/
I'm not supercharged and I don't drive 9/10ths at a driving school; I save that for racing. BTW we don't use SRF in our race cars either. Ate and Motul with frequent flushes has never let us down
Of course if SRF makes you feel more confident at 9/10ths then by all means go for it.
Keep in mind that if you're driving fast on a track, even in a school environment, it's not a matter of if something bad will happen; it's a matter of when. And it's seldom if ever brake fluid to blame; it's operator error

My point was't to have a who's the better driver pissing contest. Your coming across a bit snarky with your comments. The goal of anyone is to constantly better themselves and me driving at less than 9/10ths of my ability does not do that ( notice I said my ability not my cars). My cars limits are even higher so I'm certainly not being some reckless yahoo. And yes I'm at the point now where I'm running speeds and times faster than some "race cars" which i realize has more risk. But I am safer doing this with proper safety equipment in a thoroughly prepped car than driving down the interstate at rush hour. I's all of our choices to assume the risk when we go out on track,but it can be a very safe and addictive hobby. Of course we all spin eventually, and its rarely our cars fault but thats part of the fun . To learn from our mistakes and continue to improve is the name of the game no matter what level we are at.
The point is after hard track use at many tracks the temperature of brake fluid exceeds the wet boiling point of even 4 month old super blue due to its hydroscopic nature. I prefer using a fluid that does not absorb much water thus maintains a nice safety margin in that area, thus insuring safety and consistent pedal feel which is very important as you know.In the end its personal choice of paying 50 dollars for fluid that has a service life of 18 months or changing fluid out every couple of track weekends. No right answer its just personal preference.

[The HACK]

Actually, to do it right, PROPER COOLING is the way to go, in addition to high temp capacity. If you simply address the temperature capacity of the fluid, you're but fixing one single component and point of failure. Almost ALL track pads are capable of generating temperatures nearly double that of typical "race" brake fluids (Hawk DTC-60, for example, works up to 1600ºF, which is about 870ºC). If you can't manage to evacuate heat fast enough, you'll boil even the BEST brake fluids eventually.

Ideally, ducting, rotor thermal capacity and dissipation, brake pad thermal capacity, and brake fluid all need to be operated within their MOT parameters, and in the case of brakes, the bigger margin for error is in ducting and rotor thermal capacity and dissipation.

Especially with racing brake fluids, they don't "boil" during braking even when the pads exceed the fluid's boiling temperature. They "boil" when you don't properly cool down your brakes coming off the track, and the rotors (and pads) continue to radiate heat into the system therefore slowly COOKING the fluid to their boiling temps. While technically, some of the specs of one brake fluid is better than another, if you are not properly cooling down your brakes during the last 1/2 lap, even the BEST brake fluid will boil (again, decent track pads can generate up to 1,600+ºF, or 870+ºC heat). And all that is moot if your rotor isn't capable of evacuating that heat quickly enough.

In my not so humble opinion.

[gmd2003]

Originally Posted by The HACK

Actually, to do it right, PROPER COOLING is the way to go, in addition to high temp capacity. If you simply address the temperature capacity of the fluid, you're but fixing one single component and point of failure. Almost ALL track pads are capable of generating temperatures nearly double that of typical "race" brake fluids (Hawk DTC-60, for example, works up to 1600F, which is about 870C). If you can't manage to evacuate heat fast enough, you'll boil even the BEST brake fluids eventually.

Ideally, ducting, rotor thermal capacity and dissipation, brake pad thermal capacity, and brake fluid all need to be operated within their MOT parameters, and in the case of brakes, the bigger margin for error is in ducting and rotor thermal capacity and dissipation.

Especially with racing brake fluids, they don't "boil" during braking even when the pads exceed the fluid's boiling temperature. They "boil" when you don't properly cool down your brakes coming off the track, and the rotors (and pads) continue to radiate heat into the system therefore slowly COOKING the fluid to their boiling temps. While technically, some of the specs of one brake fluid is better than another, if you are not properly cooling down your brakes during the last 1/2 lap, even the BEST brake fluid will boil (again, decent track pads can generate up to 1,600+F, or 870+C heat). And all that is moot if your rotor isn't capable of evacuating that heat quickly enough.

In my not so humble opinion.

Agree 100% , which is why I am installing ducts and backing plates as we speak

[GuidoK]

I think it's more interesting (and more important) how you change the fluid.
I like the super blue because you have a good visual reference when the old fluid is completely flushed (in case of normal yellow fluid that is). That's a big plus imho.

Do you guys engage the abs pump (with software) when you change the fluid to ensure that all the old fluid is flushed?

[mfanatic325]

I just have the engine running and everything whenever I bleed the brakes. It's always a two-man job for me. One person sits inside and pumps the pedal while the other works the valves and checks on the reservoir's fluid levels. I figure that it wouldn't hurt to try and cycle fluid through the entire system while checking for any air or leaks. So far the pedal has come out well every time.

[The HACK]

Originally Posted by GuidoK

I think it's more interesting (and more important) how you change the fluid.
I like the super blue because you have a good visual reference when the old fluid is completely flushed (in case of normal yellow fluid that is). That's a big plus imho.

Do you guys engage the abs pump (with software) when you change the fluid to ensure that all the old fluid is flushed?

ATE SuperBlue stains EVERYTHING. Including your brake fluid reservoir. I don't like that. Personal preference.

What I usually do, is I drain the reservoir first using a turkey baster or one of those cooking syringes. Then if you follow the RR, LR, RF, LF pattern, I'd flush out 1/2 liter of fluid from the RR, then 1/3 liter from the LR, then about 1/4 liter for both front calipers, takes about 3 full bottles of Motule RBF600 to complete a full flush and take all guesswork out of it.

And without access to a GT1, there's no easy way to cycle the ABS pump while bleeding. Usually, if the pedal is unusually soft even after a full flush, I'll go drive the car around the block and activate ABS a few times, then re-bleed as necessary.