Ok so I have my AP Racing kit on and I love it. One question though..... I am using Motul RBF600 brake fluid which from what I hear is great fluid, but I also heard that I have to change it every three months.. Does anybody know if that is true??

 

The reason that people say that about the Motul fluid is that, while it has a higher boiling point than most other fluids when it's brand new, it has a reputation for absorbing moisture from the air more rapidly than other fluids, which lowers it's boiling point over time more rapidly than other fluids.

I've experienced this myself, as I used Motul fluid for a short time, and I did notice at the track that the pedal would get spongier, faster (even with a quick bleed before each track day). As a result I've gone back to the less expensive, but still reliable Valvoline SynPower fluid. I just couldn't see spending that much on a fluid that requires replacement so frequently (although I would say that changing Motul every 3 months on a street car wouldn't be necessary).

When Motul is fresh, it's great, but it loses that freshness pretty quickly. If you're not planning on tracking your car, it probably won't matter (but then why would you have an AP Racing brake kit and Motul fluid if you weren't planning on tracking your car)?

 

The car has been on the track rather often lately and hitting it again this Saturday....... Damn now I have to start looking for a new fluid........

 

GaryM05 is right on the money again! Motul is great stuff, but it's hydrophyllic (loves water) and needs to be changed out on a regular basis. Other alternatives are Ford HD brake fluid, which also has a high boiling point and the aforementioned Valvoline Synpower, which you should be able to find at the large automotive stores in Florida. BTW- which tracks are you going to down south? Road racing, drag?

 

I'm in VA. and I have been at Summit Point in West VA.

 

Opps, sorry. Paradoxically, I started my time trial career at Summit Point with the Eastern Motor Racing Association (EMRA) and had many fond moments at that track. Are you doing the FATT series there? Yes, I keep up with what's going on back east. You'll definitely need BRAKES on the Jefferson circuit!

Good luck!

 

Thats where i started racing to, mainly my dads fault when he took me for a ride along in a 944 when i was a little kid. I blame him for my addiction...

 

Its a fun track. I am trying to get a professional photographer for this weekend so maybe I can get some good track pictures.

 

Sweet.

Yeah, Motul is pretty hygroscopic, as most racing brake fluids are. The high boiling point is nice, but it must be changed more frequently. I don't know about every three months, but I flush the whole braking system every spring, and never had an issue with RBF600 under that schedule. We used it on our formula car, and had to flush the whole system out pretty regularly. The small amount of fluid in that car allows moisture content to build up pretty quick. Honestly, it was overkill to use a fluid with that high a boiling point, but we only used it because it was free. I second the Valvoline SynPower fluid. It's got a pretty high boiling point (580 degrees or so, iirc) and is inexpensive. It is much less hygroscopic than the RBF600, and so it lasts longer before it needs a flush. If you want to stick with Motul, they make a 5.1 brake fluid that is longer lasting, albeit with a lower boiling point than the RBF600.

Will