brendo

FYI

viperbob

Motul also has a 660 which has a 617 degree dry boiling point

ltc

I can't imagine running anything other than Castrol SRF.

Streak

So which is best? What's more important, wet or dry boiling point?

Edumacate me!

Circuit Motorsports

If you are concerned about the wet boiling point of the brake fluid in your car you NEED to change your fluid.

Streak

Everything concerns me. Everything. I'm a worrier.

What about Dot 3 vs Dot 4?

DrJupeman

+1
SRF FTW

Larry Herman

I feel a little differently on the subject. Sure the SRF is probably the best, but do you really need it for our cars? I run the Pentosin Racing fluid, and the DBP is 10C less than SRF. If you are changing the fluid properly, the WBP should never be a factor. Plus if your car REALLY needs such a high temp fluid, you have other issues in your braking system that you should address, i.e better cooling, different pads etc. One thing I can tell you is that the stock seals are not meant for such high temps on a constant basis. I have experienced brake O-ring failure in one weekend (they started out new) due to high brake temps, and the fluid never boiled. This happened more than once.

jaydubya

Some are limited to using stock brake calipers and rotors in a racing class...

SRF FTW.

Circuit Motorsports

Sure SRF is the best for wet boiling temp but it isn't the best for dry and in a DE/Race car there is NO reason you should have fluid that is old enough to be concerned about the wet boiling temp. You should be bleeding your brakes every weekend and doing a full flush at least once a year. If you do that maintnence you'll never have to worry about the wet boiling point (the major selling point of SRF)

The only application I personally think that SRF would be worthwhile is the tow vehicle which gets much less brake fluid attention. In a racecar there is no gain compared to other brake fluids that are much cheaper.

breale01

Somebody supplies the fluid to Porsche, but no other specs match?

jaydubya

If this were true then a fluid like Motul RBF 600 would peform just as well as Castrol SRF. I have used them both extensively and I can tell you that it's not even close.

I look at performance of a brake fluid as how often I have to bleed (after every session, after every day, after a weekend). Motul = every 1-2 sessions; Castrol = every 1-2 days.

My personal theory is that once you put fluid in your system you're dealing with the wet boiling point from that point on due to contaminants (no matter how clean you think your lines are).

Larry Herman

Know all about that Jay. I ran a Carrera with stock brakes for 15 years. I'm just saying that a few degrees should not be the deciding factor between boiling your fluid or not, and if your temps are up that high, you need to find a way to address that. Improved cooling, pads that generate less temperature or that send less heat back to the caliper are better alternatives (IMHO) than maxing out on brake fluid boiling point.

jaydubya

I don't mean to downplay your experience Larry. It's just that using Castrol SRF does indeed make a difference for my car. Believe me I would rather not spend $70 a liter on brake fluid, and I "got by" with Motul for several years before the other guys I race with convinced me to give SRF a try. After using it for three seasons, It's worth the money - even with the difference in price I spend less $ on brake fluid using SRF since I don't have to bleed as often.

I don't disagree that it may be overkill for many cars.

Having spent a ****-ton of time on the brakes in my 911SC over the last 10 years, I'm quite positive there is nothing left that can be done to improve cooling for the stock calipers and rotors beyond what I have done for my D class car (blockoff plates, ducts/hose directly to the front bumper, titanium backing plates, etc etc.). I can tell you that everyone in my car/class has the same issues.

Maybe if we could add electric fans in the lines... I looked into that at one time.

We do what we can to deal with the stock brakes - drive around the brake limitations, keep the brake system in top condition, bleed frequently, use the best fluid available and keep a supply of caliper rebuild kits on hand.

Cheers,

Jeff

DrJupeman

I agree with this and it also becomes why Castrol really isn't as expensive. You can bleed less, even if still regularly, which saves you time ($) and nets out on the cost of fluid.

All I know is that since I switched to SRF, I bleed less and my brakes feel better (was using Motul before). Win-win for me: less work, better brakes, high confidence. I was a skeptic once about "liquid gold" (what the SRF brand manager calls it), too.

But this is a religious argument. We might as well start talking motor oils...