Brake fluid for track car

[StuOwen86]

Well I'm hopefully doing the fluids on my 172 Cup track car (Engine Oil, Gearbox Oil and Coolant) and was wondering as I cant decide what brake fluid to use, I have mates who do sprints and track days who use either the Motul or Castrol (they run a Supercharged BMW Mini and an E46 M3) so I'm trying to decide if to pay the extra for either the Motul or Castrol. I'm running Brembo HC disc's and carbon Lorraine pads (not sure which). I thought I had boiled the fluid on my last outing at Oulton but after searching on here I found that the brake res might be filled up to the MAX line (will check next time I'm at the car) causing the slight bubbles from the top as I drove home and had no issues and didn't feel like the fluid had boiled just had slight fade which I think was from the pads as it was gradual (at the minute I only do 1 warm up lap then about 4-6 laps, then a cool down lap) , So I thought I might as well give the brake fluid a refresh as I'm not sure how old it is.

And also with the higher end fluids is it true they have to be changed more often due to them being more hygroscopic?

Prices are approximate and I only used Opie Oils as a reference.

ATE Super Blue or Gold @ £15 a litre
Motul RBF660 @ £34 a litre
Castrol SRF Racing @ £42 a litre

Thanks.

 

[JamesBryan]

Currently use ATE.

I'm no racing driver, so I can't see myself boiling it yet. It's cheap enough to change a few times a year too.

 

[JamesBryan]

With regards to the boiling points.

ATE is 280 degrees
Motul is 325 degrees
Castrol just says over 300

 

[StuOwen86]

Was going to add the boiling points assume WET boiling point is the one to look out for.

 

[JamesBryan]

Was going to add the boiling points assume WET boiling point is the one to look out for.

If you're changing it fairly regularly then wet boiling points won't really apply as much because it won't have had much moisture absorbed into it.

But it is worth noting, yes.

 

[StuOwen86]

Depends which one I choose lol don't mind changing the ATE a few times a year but the Motul or Castrol at the price I would probably refrain from regular changes, and depending how much time I get on track days to be fair.

 

[JamesBryan]

If it was me and I was changing from the ATE, then i'd go for the Motul. It doesn't seem to badly priced but the Castrol is a fair bit more in comparison.

But I suppose if you want the best, then you have to pay the money lol.

 

[NorthloopCup]

I use the motul RBF600 in mine without issue on track.

 

[StuOwen86]

Is there a MOD where you can move the brake reservoir out of the way so its not above the manifold? Or just make a heat shield for it?

 

[...]

SRF for me , used it for years and swear by it

 

[NorthloopCup]

Is there a MOD where you can move the brake reservoir out of the way so its not above the manifold? Or just make a heat shield for it?

It's a megane reservoir that you use to relocate it. @Tony Hunter will tell you the model if he can remember.
I've never had an issue with regards heat and the fluid reservoir on mine and I kick the s**t out of it tbh. For the new engine though I'll have no choice but to have a heat shield.

 

[eastlmark]

Castrol SRF transformed the brakes on my old race spider, but they took a right hammering on track so may be over the top for general use. The cost of it made me very miserly when bleeding as well and as for binning used fluid every year that was heartbreaking!

 

[eastlmark]

did mean to add, Mark Fish always recommend AP600

 

[Bunta]

Just use ATE and you wont have any problems, people must be mad paying £42/litre for castrol srf in a lightweight clio..
I used to use gulf rf800 and never had that boiling in a 1150kg mr2 so that would be another option and is around £20/l i think

 

[...]

i used to use SRF in a 500kg westfield , on slicks anything less got way too hot .

 

[harry289]

I use Millers Motorsport 300 DOT 4 in my race car

 

[RichB]

I boiled RBF 660 on track a few weeks ago, I was on track for waaay to long though as I didnt stick to 15min sessions. Ill be using ate super blue as its cheap enough to change after each track day.

 

[Cupman29]

Motul 600 for me. Never boiled it yet with some 30min sessions.

 

[Joe#]

I've got some Motul 660 ready to go into mine, I'll report back.

 

[Cupman29]

660 will need changed more frequently than 600 but will have a higher boiling point.