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-   Suspension | Chassis | Brakes -- Sponsored by 949 Racing (https://www.ft86club.com/forums/forumdisplay.php?f=59)
-   -   Torque RT700 - DOT 4 Racing Brake Fluid - Review (https://www.ft86club.com/forums/showthread.php?t=47686)

churchx 05-25-2023 12:50 AM

Are higher boiling temps brake fluids more hygroscopic? Indeed, common trait. Do some raceteams (if they have means & budget) for high end racecars choose to flush after race because they intend to keep car in absolute top state, not even 1-2% worse? - probably. But that doesn't sound to me that fluid used became "unusable" or degraded past level most of us will consider as unusable "after single race". Also wet (degraded due absorbed moisture) temps of some brake fluids may still be high enough or higher then that of generic brake fluids. Due legal reasons (to keep street legal locally) i'm limited to stock brakes, pads/fluid is only thing i can upgrade, so that's what i do. From my experience, on my car, with my stock brakes, with my track use, cheaper aftermarket fluids like RBF600 needed more frequent flushing, while i used Pmu Gfour-355 for season. So "high end brake fluids must be flushed after every race, hence shouldn't be considered" imho is not exactly best conclusion to draw either. My limited (stock) brake thermal capacity means that with rest being same brakes vs BBK will run hotter and stay hot longer .. higher temp range pads & fluid seem to me as justified & needed in this scenario.

ZDan 05-26-2023 12:38 PM

Quote:

Originally Posted by churchx (Post 3582064)
Are higher boiling temps brake fluids more hygroscopic? Indeed, common trait. Do some raceteams (if they have means & budget) for high end racecars choose to flush after race because they intend to keep car in absolute top state, not even 1-2% worse? - probably. But that doesn't sound to me that fluid used became "unusable" or degraded past level most of us will consider as unusable "after single race".

In my experience, fresh high-temp "racing" brake fluid has only been usable for a single track day, which for me consists of 4x 10-15 minute sessions. While parts store DOT4/DOT5.1 lasts half a season or about 6 track days before caliper bleed.

Quote:

Due legal reasons (to keep street legal locally) i'm limited to stock brakes, pads/fluid is only thing i can upgrade, so that's what i do. From my experience, on my car, with my stock brakes, with my track use, cheaper aftermarket fluids like RBF600 needed more frequent flushing, while i used Pmu Gfour-355 for season. So "high end brake fluids must be flushed after every race, hence shouldn't be considered" imho is not exactly best conclusion to draw either.
Fact is 90% of us who track these cars will be just fine with "normal" parts store DOT4 or DOT5.1. IMO AP Racing's recommendation for a street FT86 doing HPDE makes perfect sense. Most likely there is no need for any special higher-temp "racing" brake fluid.

Quote:

My limited (stock) brake thermal capacity means that with rest being same brakes vs BBK will run hotter and stay hot longer .. higher temp range pads & fluid seem to me as justified & needed in this scenario.
But have you tried tracking with normal DOT4 or DOT5.1? For me, that has always been sufficient in every car I've tracked.

churchx 05-26-2023 06:31 PM

Quote:

Originally Posted by ZDan (Post 3582219)
But have you tried tracking with normal DOT4 or DOT5.1? For me, that has always been sufficient in every car I've tracked.

Hmm .. hate to admit, but haven't exactly tried :). As in my two very first trackdays ever, that were on stock primacies, stock alignment, stock fluid, stock brake pads .. imho brake fade experienced was more from overheated/glazed pads, not boiled fluid, though i might been wrong .. when started feeling braking degradation, just went for cool off lap and returned to pits .. while later i changed both pads & fluid, so hard to tell, which did hit limit first ..

strat61caster 05-26-2023 07:34 PM

Arguing about people “wasting” $40/year on Castrol SRF for their >$15000 track car is silly.

ZDan 05-26-2023 07:50 PM

Quote:

Originally Posted by strat61caster (Post 3582277)
Arguing about people “wasting” $40/year on Castrol SRF for their >$15000 track car is silly.

Not arguing, discussing.
I think it’s not a bad idea to let people know they have cheaper and easier-to-get options for trackworthy brake fluid, that will most likely last them for more events between bleeding flushing vs more expensive “racing” brake fluid. Just sharing my experience here…

ZDan 05-26-2023 07:55 PM

Quote:

Originally Posted by churchx (Post 3582267)
Hmm .. hate to admit, but haven't exactly tried :). As in my two very first trackdays ever, that were on stock primacies, stock alignment, stock fluid, stock brake pads .. imho brake fade experienced was more from overheated/glazed pads, not boiled fluid, though i might been wrong .. when started feeling braking degradation, just went for cool off lap and returned to pits .. while later i changed both pads & fluid, so hard to tell, which did hit limit first ..

Wouldn’t risk much to try “normal” DOT4 or 5.1 at the track with your trusted racy brake fluid on hand for quick flush if you need it. I bet you won’t though!

CSG Mike 05-26-2023 08:59 PM

Quote:

Originally Posted by Captain Snooze (Post 3581964)
I recently spoke to the AP Racing distributor in Aus regarding their super duper Radi-CAL R4 Brake Fluid. I was told that it gets flushed after every race. I was told that the higher the performance of a brake fluid the more hygroscopic it becomes. After telling him I wanted to track my road car he recommended AP Racing 5.1.

When you're racing 6 figure cars, you're not gonna skimp on relatively small maintenance items. Similar cars will likely get a full fluid change, as well as fresh rotors and pads, and maybe even a caliper swap to a freshly serviced set of calipers *every race*.

You don't want to risk the car or a loss to something small, when you're spending 6-7 figures a year to run the car, and the operation of the car is measured in double digit spend per kilometer.

Muskoka800 06-01-2023 12:28 PM

FYI All,
I messaged Torque yesterday asking for Canadian dealer info.
Last night Michael Wachholz replied.
Sadly he has no Canadian dealers at this time. But suggested ordering via their website and advised they are re-running their 4 for the price of 3 promo.
Food for thought.

Muskoka800 06-04-2023 12:02 PM

Any info/results for Motul RBF700?
I don’t see Torque RT700 on the CSG web store.

Lynxis 06-05-2023 10:23 PM

If you're having trouble getting a hold of RT700, I'm just going to recommend Canadians source Castrol SRF React which is a similar class of fluid. A single flush of the stuff is completely fine for a full year of regular autocross and track days for me. It also has the benefit of not getting highly viscous in low temperatures like many other fluids given that my brake pedal feels exactly the same in -30c as it does at the end of 20 minute sessions on the race track and that's not something I can say the same about with any other fluid I've personally used.



I'll note that I've run the same fluid for over 2 years without even partial bleeds and it's handled it just fine and although my last track day was totally fine, the fluid that came out last weekend was quite cloudy/milky so I'm not recommending anyone else actually do this, I think it should still be flushed annually at least, but if you're in a pinch, it looks like you can stretch it out a bit.


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