dzombek

I was at Mid-Ohio this weekend and noticed something very disconcerting. While under hard braking into 7 I noticed that my brakes seem to fade quite a bit. If I start braking hard in a smaller braking zone to get the car slowed down the brakes will slow my momentum.

But if I start braking early and extend the braking any more I notice that the brakes fade. But, if I lift off the pedal and re-apply pressure the brakes come back nicely and the pedal is hard once again.

Since brake system is fairly simple, it has to be my brake pads not being adequate(Mintex c-tech), my brake lines, or heat. I don't think it's my master cylinder as the brakes seem fine through out the rest of the track. Granted those braking zones don't need that much brake to slow you down.

Any thoughts?

Z

Jeremy Himsel

I had the same issue years ago with the Mintex pads. I swapped them out for Hawk HP Plus's and never had fade again during DE's.

ninefiveone

Chances are a brake fluid flush will resolve a lot of this but this is also a lesson in brake management.

At some point you'll need to step to better brake pads but that should not be the first thing you do. Just like people shouldn't jump to track tires or track suspension, figure out how to make the most of what you have first.

Being long and light on the brakes will lead to brake fade and doesn't do a very good job of managing weight transition to your advantage.

I'm not saying to jab at the brakes but firm short usage is a lot more effective, is better at avoiding fade and ultimately will lead to better lap times.

kasturbo

My guess would be the fluid. Did you flush the fuid before the event? What type of fluid are you using. It wasn't a very hot day, so that shouldn't have been the issue.

jerome951

Turn 7 is really hard on brakes because it's high speed and downhill to boot. If you were getting fade due to boiling fluid, you should have also seen a mushy pedal at T9 (the hard right-hander w/ the downhill braking zone after Madness) assuming you were pushing the car.

It could be any of the reasons you mentioned since the rest of the track has relatively light brake zones, though brake lines and pads are unlikely since a re-application of the brakes solved the problem (pads don't cool that much w/ a simple lift). Have you verified the master cylinder isn't leaking?

What about entering the carousel? Were you hammering the brakes there and did you experience any fade?

Did you try to flush the fluid between sessions? If so, did it make a difference?

[soapbox] I disagree with ninefiveone on one point. Never go to the track w/ street pads, especially with a relatively heavy and hi-powered car like a turboS, unless you're a pure beginner and not pushing the car (which David is not). In my view brake pads are a safety item, not a performance upgrade. You wouldn't strap on an old-fashioned leather helmet and learn to do the best with what you have. Ever see someone wondering why their car won't brake very well then pull their street pads to find them glazed (seen it at Mid-O)? Or someone pull into the pits with their brake pads on fire (seen it too)? You're just not using a component of the car in it's intended operating range.

I agree about ninefiveone's comment about R tires. However, in this case, a good street tire is up to the task. You wouldn't track the car w/ $30 Pep Boy specials and wonder why they chunk and delaminate when you start driving hard. They're outside their operating range. Same goes with brake pads.

Get a good set of track pads and swap them out between events. Very easy to do. People claim that street pads are cheaper, but when you wear out a set of $40 street pads in a weekend, but good track pads which cost $180 last for 5, which is cheaper? Plus, you get the added safety and reassurance that if your car isn't stopping, it's not because of the pads. [soapbox/]

Whew, I'm done....

dzombek

I didn't see a mushy pedel going into 9 only when diving into 7. One thing that it could be is that I am not manageing the brakes well(yet). I did notice if I did 85% of the braking from speed at first the pedel felt okay. But if I tried to extend the braking zone, the fade occured. And a quick(smooth) release and re-apply brought the brakes back.

I didn't change the fluid at the track for the above reasons, didn't think it was the fluid. I just started to "change" my management of the brakes. Slowed down on the straight and started to press on the brakes more to get the car slowed quicker preventing the extended braking zone.

I will plan to try a known pad like PFC or Hawk Plus pads after I use this mintex pads for one more event. At that event I will work the brakes more affectively, by doing ~80% into the turn to make sure I shorten the zone. That way I build a certain amount of control that I can build from. And then move to another pad as needed.

ninefiveone

I'm going to have to agree and disagree on the pads.

Every street pad will end up glazed under proper track usage. This is very true. I've gone through just about every street and track brake pad available for stock 951 calipers and am only now looking at a brake upgrade not because the bigger brakes will stop me better (only marginally) but because pads will last longer and I'm tired of replacing $200+ track pads after one track weekend.

But I do like people staying on street pads for a good while to learn a couple things. Hard, short and aggressive use of the brakes which results in much better braking AND fade avoidance, as well as what to do when the brakes are fading. I think there's a lot of value to learning how to handle fade situations at novice speeds before coming across fade at "angry" speed. Especially if you progress to the point where you're tracking with tube frame cars or open wheelers who are not going to be forgiving of drivers who are just learning what to do with a car that's about to be really out of sorts.

David - everything you're saying points to: Use the brakes shorter and harder. Why are you trying to extend the braking zone? If there's anything I can tell my students and just about any driver i've ridden with, get on the brakes later and WAY harder. Not to annoy jerome but I'd much rather you figured out your braking technique first, played with it to some degree, and then moved on to other pads.

Don't become that guy who brakes way earlier and lighter than necessary. It's a slow way around the track.

But Jerome is very right that you'll want track pads sooner than later.

dzombek

ninefiveone, I have to agree with what you say and I will also ride along with Jerome on his points. I guess the long and short of my extending the braking zone was to get used to the braking efficicency of the car. And when I felt the brakes fade, it put a sense of "oh &^%" in my brain and it wouldn't allow me to consistently press on the brakes harder and later prior to turn in.

But the odd thing is that on turns like 9,10, 11 at MO, I am not as worried about the fade becuase I am braking like I should, late and hard. And I am pushing the car 8-9/10ths carrying speed. I guess the speed differential between turn 7 and the rest of the track weighed on my mind and caused me to brake early.

Knowing now that I am to blame for most of the fade I will most certainly correct that at the next event. Becuase that not only hurts my learning and prevents my ability to advance as a driver, I can see it being unsafe for the driver behind me.


Thanks
Z