Tracking a daily driver - how often to replace high temp brake fluid?

[VroomVroom]

Hi,

Started tracking my 2010 Camaro 2SS and really like driving on the track. Started by replacing the brake fluid with high temperature brake fluid for safety (since everyone told me it was too heavy to be a track car and would wreck my brakes, HA) and then did a driving school day where I learned the basics. Went again in July (so much fun!) and am scheduled for another day in August. I see myself going to the track no more than once a month, but not less than 4-5 times per year.

I love this car, and she's also my daily driver, because I prefer her to my other car! When I am at the track, I have a ton of fun, but I know I don't have special brake pads or rotors and the car is heavy, so I tend to drive very smoothly without relying on extremely heavy braking (yes, my lap times are slower as a result, but I keep up with the pack and pass enough other cars in my novice sessions that I can't feel like I am that slow!) I am positive that the car is barely breaking a sweat in my sessions- I did a double session of 40 minutes carrying as much speed as I felt confident I could handle, and the transmission temp was barely elevated, no brake fade, felt great.

I was told that the high temp brake fluid needs to be replaced more often- I was thinking once a year, but a friend told me after every three track days!? Really? If I'm not driving it that hard, can I stretch that out further? How do I know if I am driving it hard? I don't think I'm getting to more than about 5000 RPMs max and I have apps that track my speed/braking/G-forces, etc, but I feel like the car was made for this! Is there any benchmark that differentiates the track driving from driving fast and hard normally?

I would also like to know if there are any recommendations on things to check in general between track days - obviously fluids, brake pads, tires, but are there any things that I should watch out for as warning signs? I'm very mechanically inclined for a female, but don't have a lot of experience with more complex newer engines.

New enough to the sport that most tips and comments are helpful! Thanks!

[Norm Peterson]

I bleed my brakes before every track event. Not a complete flush, just whatever it takes to have clear fluid coming out of every bleed fitting (for me, this has usually been about half a liter). That gets the most severely beat-up fluid out of the system and probably does end up changing essentially all of the fluid every 3 or 4 times out. Just not all at once. Motul RBF600, FWIW.

I would think that SS rotors (14" / 14.4"?) are big enough to support running in at least intermediate-level groups, but I think at that level you would definitely need more track-focused pads. You'd want them, at least for the greater confidence that they'll still be there for you toward the end of a session. I went to Carbotech's XP8 pads for my second track day ever, up from a "performance street" pad that was only slightly better than OE. "Outgrew" those about four events later, moved up to XP10's, and am about to go up one more step to an XP12/XP10 combination.

My only potential disclaimer here is that it's based on MT experience only; if your car is an automatic it probably tends to be a bit harder on brakes and you might want to move up to track pads a bit sooner or choose a higher rated compound for at least the front brakes.

Getting hard on the brakes quickly and hard (as opposed to gradually like almost everybody always does in street driving) will have you catching lots of drivers with comparable track experience under braking. Do this smoothly, more like quickly squeezing on them vs the panic-braking stomp that may be your only previous experience with fast hard braking.

One school of thought has higher temperature rated track pads behaving as better heat insulators where the caliper pistons, seals, and ultimately the fluid are all concerned.

Keep an eye on your rotors. They will most likely "heat-check", or develop small random-direction micro-cracks. If you can catch your fingernail on them, that rotor and its twin on the other side are all done.


Benchmarks? You're using the entire track width because you have to, not because it feels "cool" to be driving "on the racing line". On street tires, you expect them to be talking to you in the corners instead of taking the sound as the precursor to imminent disaster. You may be steering the car with the throttle in some of the longer turns.


Welcome to the addiction.


Norm

[backeddy]

I DD my 1LE and track several times a month....I am probably one of the only ones here who has an original clutch that has lasted this long (1300 laps and 23k miles) ( and notice I am NOT talking about the brakes). I completely flush the $$$ Castrol SRF every time I go. Please take my advice, because if you don't, you will be replacing your clutch system very soon. GM's piss poor slave design introduces clutch dust to the fluid system each time you shift. It will completely contaminate the fluid and you ARE GOING to have a failure. My method is to pump the clutch 25 times in a row, then take a mitevac and suck all of the fluid out of the master (you will see how contaminated it is), then flush the brakes, then do the 25 pumps again and repeat until there is no more contamination. It is expensive, but way cheaper than a clutch or the collateral damage that may occur from a failure.... You are not fast enough to worry about the brakes yet, so don't, after you have boiled the fluid, come back and we will talk about the brakes...

[Joseph1LE]

Originally Posted by backeddy

I DD my 1LE and track several times a month....I am probably one of the only ones here who has an original clutch that has lasted this long (1300 laps and 23k miles) ( and notice I am NOT talking about the brakes). I completely flush the $$$ Castrol SRF every time I go. Please take my advice, because if you don't, you will be replacing your clutch system very soon. GM's piss poor slave design introduces clutch dust to the fluid system each time you shift. It will completely contaminate the fluid and you ARE GOING to have a failure. My method is to pump the clutch 25 times in a row, then take a mitevac and suck all of the fluid out of the master (you will see how contaminated it is), then flush the brakes, then do the 25 pumps again and repeat until there is no more contamination. It is expensive, but way cheaper than a clutch or the collateral damage that may occur from a failure.... You are not fast enough to worry about the brakes yet, so don't, after you have boiled the fluid, come back and we will talk about the brakes...

What are you thoughts on separating the clutch/brake reservoir and getting the aftermarket little clutch reservoir like the one the f-bodies had? I found it odd when I first popped my hood and saw that the clutch and brakes shared a fluid reservoir. Figure every time I give it a hard shift clutch dust will get in there and as a result contaminate not only the clutch fluid but the brake fluid since it's all shared. Doesn't make much sense, but my fluid still looks new as can be after 2500 hard miles so I guess it can't be that bad of a design.

[Norm Peterson]

Originally Posted by backeddy

You are not fast enough to worry about the brakes yet, so don't, after you have boiled the fluid, come back and we will talk about the brakes...

I'd rather err on the side of caution than take a chance with DOT 3. I agree that certainly in the early going, SRF is way better fluid than necessary. But I do think that either ATE200 or RBF600 would be appropriate for a novice who intends to stick with the hobby and who will probably become an intermediate before too long.


Norm

[backeddy]

Personally, I would not separate them, as you will then be introducing the contaminates into a small container, thereby increasing the concentration of the contaminants that cause the failure....Just my .02 Like Norm said, you do not need the SRF yet, but DO NOT depend on DOT 3. All of the ones he suggested are fine, along with Amsoil 600.

[VroomVroom]

Thanks very much for the discussion - I've been happy with the RBF600 fluid and definitely wouldn't have wanted to try the track with the DOT3 fluid, everything got really hot! I've definitely looked at the rotors carefully, had a few people tell me they were remarkably smooth and even, so I must be doing something right, or going way too slow!

One question for Norm- what do you mean by "Getting hard on the brakes quickly and hard (as opposed to gradually like almost everybody always does in street driving) will have you catching lots of drivers with comparable track experience under braking." Do you mean catching like catching up to or catching like seeing other drivers under braking?

I definitely like your benchmark point of using the entire track width because you have to, not because it feels "cool" to be driving "on the racing line" - very good point. And yes, I like the tire sound in the corners, I wasn't sure if that was a good noise or not, but sounds like having noise but no slip (still have traction, but just at the limit) is where I want to be? I'm on a new set of the Pirelli P-Zero stock tires, I've liked them as a good every-day tire that has held up well on the track so far. I'm down to 10/32" tread after two track days and 3 months of daily driving, which seems reasonable to me. Seem to end up with a lot of melted rubber on the chrome part of the wheels, but I guess the heat just makes the tires stickier?

[VroomVroom]

Oh, and I almost forgot - if I am using the paddle shifters, will the automatic still be harder on brakes? Is the automatic harder on brakes because it's not necessarily using engine braking? My first track day I drove it in the sport mode without using the paddle shifters, and I have to admit, I was pretty impressed with the way that the car "learned" that we were playing hard and fast - shifted down better than I thought she would. Next track day I used the "sport mode" with the "competition mode" (Stabilitrak and traction control off) and that was even better- now I know the track I feel like I can add paddle shifting next time. Tips? Default third gear, down to second for tight tight turns and maybe up to fourth for straight, or stay in third? Guess the RPMs will tell me, right?

Which also reminds me- I get up to about 5000 RPMS, and 6-8k RPMs are red on the dial in the car. Is that red like "don't get into this part" or red like "don't stay in this part for a long time"?

I hope these questions are amusing and not idiotic...

[Norm Peterson]

Originally Posted by VroomVroom

One question for Norm- what do you mean by "Getting hard on the brakes quickly and hard (as opposed to gradually like almost everybody always does in street driving) will have you catching lots of drivers with comparable track experience under braking." Do you mean catching like catching up to or catching like seeing other drivers under braking?

Catching up to. A gentle braker will be on the brakes sooner, before you're even beginning to get off the throttle. And longer, because he still has to get down to about the same speed and he's braking over a longer distance than you. He might have slowed from 100 down to 85 at the point where you're just starting your deceleration, so there would be some distance over which you're closing up the distance to him at a speed difference varying up to 15 mph.

Or think in terms of the time between the two of you passing the same point, not just in the distance between (which will still close up even if the two of you brake at equal rates). You might be 150 feet behind an otherwise identical car down one straight neither gaining on him nor losing anything. That'd be about 1 second at 100 mph. Say you gain half a second under braking to a 50 mph corner, so you'll be a little less than 40 feet behind him through the corner. Granted, he'll still be able to get on the throttle about half a second sooner than you can, but you'll still be closer to 50 feet behind him all the way down the next straight than the 150 you were down the previous straight. Lather/rinse/repeat.


Norm

[Norm Peterson]

Originally Posted by VroomVroom

now I know the track I feel like I can add paddle shifting next time. Tips? Default third gear, down to second for tight tight turns and maybe up to fourth for straight, or stay in third? Guess the RPMs will tell me, right?

"Use the force, Luke".

Seriously, listen to what your engine is trying to tell you (and compare that to how hard you're driving, which might not always be "8/10ths" or whatever). And pay attention to where on the track you're considering a shift - there are situations where short-shifting slightly will be of advantage (such as to avoid making that shift midway through a fast bend).

Which also reminds me- I get up to about 5000 RPMS, and 6-8k RPMs are red on the dial in the car. Is that red like "don't get into this part" or red like "don't stay in this part for a long time"?

I hope these questions are amusing and not idiotic...

At some rpm, somewhere beyond 6000, your car's PCM will step in (cutting fuel and/or retarding spark) and call a halt to the skinny pedal fun in that gear.

Unless you're time-trialing and are having your laps electronically timed, there isn't any real need to be up there beyond 6000. So relax a bit and try to keep the engine between maybe 4000 and 5800, maybe 5900 most of the time. A brief excursion to 6000 that avoids an upshift just before hitting a braking zone is the most common exception I can think of.

Keep an eye on coolant temperature, particularly since your AT dumps most of its excess heat into it.


Norm

[VroomVroom]

Sweet, thanks for the responses. Lots to learn and practice!