Roadracing brake issues

[Schmitty5]

Hey dudes...

I've been having some brake issues and wondering what you all do to keep them cool. The pedal gets spongy quite often and its concerning. Just looking for some pointers or advice on what you do to handle your brakes at the track.

Current set up :
Pads - xp 10
Fluid - Motul 660
Lines - stock
Tires - Hankook Venuts V12 (street tires)

I drive in the intermediate group, and feel my brakes (and tires which I will soon upgrade) are whats holding me back from going into advanced. Any advice/opinion is greatly appreciated.

If nothing else, what brake lines do you use? I've looked at a few companies but it seems like a stainless steel line is... a stainless steel line, so I'm not sure theres a difference in brands.

P.S. Some vid of me last year for you to flame
https://www.youtube.com/watch?v=YxkRsxpDfX8

Thanks!

[shamie]

SS lines won't hurt and it's a pretty cheap way to find out if they're your problem.

I run Stoptech everything and Wilwood 570 fluid and don't have many issues. I did add some ducting recently. It doesn't seem to affect the braking but it looks like the pads are lasting longer.

[hartlch]

How often do you bleed your brakes? Agree that new lines are a relatively inexpensive thing to try. What other tracks do you run? Is braking only a problem at some of them?

[GroceryGtr]

SS lines are SS lines to a certain extent. What separates the good ones from the bad ones are the fittings and the process, or lack there of, to consistently crimp them. Buy from a reputable shop, such as one of our vendors. Ebay SS lines are a dice roll for a track setup.

What rotors are you running? Common issues are crap quality rotors, not properly bleeding the system, not properly seating the pads, and bad fluid.

Hardware aside the biggest issue I see with newer drivers cooking brakes is technique. Newer drivers who don't know the track tend to hover brake into corners extending the amount of time the pad is in contact with the rotor which leads to a ton of unnecessary heat. Pay attention to the brake zone signs(or cones) and be confident with your braking. It should be a firm smooth motion into full brake, get your downshifts in, and then fade off of them as you turn in. Also look at your line. Sometimes running a new line will make a big difference.

At a new track or if I'm in a new car I always start slower and get my braking figured out then increase my speed. Its not just about learning the track, its about learning how to efficiently apply the skinny pedal and the brake pedal. I can't count the number of times I've outbraked guys in much better cars, or the number of times I've had pros ruin me in the brake zone in what is the equivalent of a minivan.

So most of the hardware stuff is fairly easy and cheap to check and change. Once that is squared away take a focus on your braking technique, there is always room for improvement.

[Schmitty5]

Originally Posted by GroceryGtr SS lines are SS lines to a certain extent. What separates the good ones from the bad ones are the fittings and the process, or lack there of, to consistently crimp them. Buy from a reputable shop, such as one of our vendors. Ebay SS lines are a dice roll for a track setup. What rotors are you running? Common issues are crap quality rotors, not properly bleeding the system, not properly seating the pads, and bad fluid. Hardware aside the biggest issue I see with newer drivers cooking brakes is technique. Newer drivers who don't know the track tend to hover brake into corners extending the amount of time the pad is in contact with the rotor which leads to a ton of unnecessary heat. Pay attention to the brake zone signs(or cones) and be confident with your braking. It should be a firm smooth motion into full brake, get your downshifts in, and then fade off of them as you turn in. Also look at your line. Sometimes running a new line will make a big difference. At a new track or if I'm in a new car I always start slower and get my braking figured out then increase my speed. Its not just about learning the track, its about learning how to efficiently apply the skinny pedal and the brake pedal. I can't count the number of times I've outbraked guys in much better cars, or the number of times I've had pros ruin me in the brake zone in what is the equivalent of a minivan. So most of the hardware stuff is fairly easy and cheap to check and change. Once that is squared away take a focus on your braking technique, there is always room for improvement.

Thanks for the advice. I definitely hear you on the brake usage and I am sure to not ride the brakes I'm either on hard on the gas or hard on the brakes.

I'm running premium rotors from carbotech. Nothing too cheap but not slotted or drilled (I'm not a fan, I just think they eat through your pads more). The biggest technical thing I lack is heel toe shifting. Its a difficult thing that just takes time to really get down (in my opinion). I'll get there though.

@shamie Do you have any pics of your ducting? I'm very interested in what you came up with. Thanks

@hartlch - I bled the brakes last October but haven't driven more than 100 street miles since then. The car is strictly a toy. I've only raced on 2 different tracks now. The last track I was on I actually boiled my brake fluid and roasted my calipers (due to shitty pads and fluid). Now I've upgraded and I think getting SS lines might help a bit.

[hartlch]

- I bled the brakes last October but haven't driven more than 100 street miles since then. The car is strictly a toy. I've only raced on 2 different tracks now. The last track I was on I actually boiled my brake fluid and roasted my calipers (due to shitty pads and fluid). Now I've upgraded and I think getting SS lines might help a bit.

OK, it was hard to tell from the video, but I did not see any hard braking in that clip. I think the most was maybe .5 g. The comments from @GroceryGtr regarding braking technique match what I was thinking. Newer drivers tend to be on the brakes far too long. Seems counter intuitive that braking much harder is easier on the brakes. What have your instructors said about your driving?

You should bleed your brakes. The fluid can absorb water even if not driven. Definitely bleed at least at the start of track season. And it doesn't hurt to bleed some after every track weekend - especially if you know you overheated them.

[Code Monkey]

If you have many situations like in the video where you catch up with a car in front and have to brake hard because the guy decides to park his car going into a corner, then I can see overheating the stock system pretty quick. If you still overheat with no traffic, reduce the brake effort to 80 percent and see how it goes. If still boiling fluid, switch to Castrol SRF. If still problems, need bigger brakes with more thermal capacity and/or brake ducts.

[nindoja]

Originally Posted by Schmitty5 Hey dudes... I've been having some brake issues and wondering what you all do to keep them cool. The pedal gets spongy quite often and its concerning. Just looking for some pointers or advice on what you do to handle your brakes at the track. Current set up : Pads - xp 10 Fluid - Motul 660 Lines - stock Tires - Hankook Venuts V12 (street tires) I drive in the intermediate group, and feel my brakes (and tires which I will soon upgrade) are whats holding me back from going into advanced. Any advice/opinion is greatly appreciated. If nothing else, what brake lines do you use? I've looked at a few companies but it seems like a stainless steel line is... a stainless steel line, so I'm not sure theres a difference in brands. P.S. Some vid of me last year for you to flame https://www.youtube.com/watch?v=YxkRsxpDfX8 Thanks!

Saw your video on FB the other day and meant to post up. I'm so jealous to see you out on that track; it makes me miss Summit Point dearly.

Surely with all your video gear you could get a second camera setup pointed at your feet then sync to see how long and hard you are breaking?

[Schmitty5]

Originally Posted by nindoja Saw your video on FB the other day and meant to post up. I'm so jealous to see you out on that track; it makes me miss Summit Point dearly. Surely with all your video gear you could get a second camera setup pointed at your feet then sync to see how long and hard you are breaking?

Shane! Join the party man why not? Yea I'll be working on a really awesome set up as far as recording video goes. I'm currently in the process of completely stripping the car, which will allow for lots of mounting options. Harry's Lap timer is also amazing and really ads to the racing experience. Haven't thought about placing one by my feet but thats actually a great idea.

[nindoja]

Originally Posted by Schmitty5 Shane! Join the party man why not? Yea I'll be working on a really awesome set up as far as recording video goes. I'm currently in the process of completely stripping the car, which will allow for lots of mounting options. Harry's Lap timer is also amazing and really ads to the racing experience. Haven't thought about placing one by my feet but thats actually a great idea.

Because I'm 10 hours away, and if I'm driving 10 hours to a track it's going to be VIR.

Stripping the car down, nice! That's going to be in my future on the 6, if I ever get my engine back in there and running.

[gotovato]

Currently running hawk HP plus pads, stop tech slotted rotors and stop tech 660 fluid. Can't say I've ever had brake issues...yet. And I push hard. On the track. On the back roads. I find trail braking really helps my car maintain traction and rotate wonderfully. Heal toe is practice and I find it's not too bad in this car. the difference good pads and fluid makes is crazy. I tracked my old car on full oem brake setup a few times. Second lap in I had 0 brake pedal and it was terrible. Highly recommend good fluid and pads. Also I see you make similar power to me, better tires wouldn't hurt when the time comes. I find my 255 wide re71 are beautiful for both street and track use.

[GroceryGtr]

sitting/storage kills brake fluid life. All my track cars get a complete drain/bleed prior to the new driving season and then as needed throughout the track events(usually I can get away with a single mid season bleed). SS lines only help with an overall pedal feel, they won't solve spongy pedal due to heat. Certainly wont hurt for the money, but the more I think about it the less help I think they will be.

Code Monkey makes a good point, other idiot drivers will definitely have an effect on your braking. with the Abarth I run into it all the time where high HP cars with rookie drivers will blow by me in the straights only to get on the brakes way to early and cause me to have to check up.

Regarding rotors slotted rotors may help as well by reducing the amount of time you need to be on the brakes. Short length heavy pressure braking is much easier to dissipate heat than longer length 'half pressure' braking. Slotteds have a much better bite than solids, especially forward facing slots. Though you are correct they eat pads quickly. Might be worth it to look into directional vain rotors as well. Every bit of extra air helps.

All that being said I think a fresh bottle of brake fluid and a complete cross corner bleed is a very good starting point.

[shamie]

I bleed my brakes (not fully, just the caliper and a little more) after every track weekend. Gets whatever fluid that's been to the surface of the sun out of there.

I'll see if I can post some pics up tonight. I was going to use these ducts
https://www.amazon.com/gp/product/B0...?ie=UTF8&psc=1
in the fog light holes but there just wasn't enough room. I ended up zip tying the 3" hose
https://www.amazon.com/gp/product/B0...?ie=UTF8&psc=1
to some spare fog light housings to hold them in that hole then routing the hose to the front/top of the lower control arm and zip tying them there too. I squashed them into an oval shape to keep them away from the axles/boots. They're pretty much held in place between the engine and splash shield. It's not the most optimum set-up but it seems to be helping and hasn't moved/come loose in 2K miles (inc. 6 track days). I'll probably remove it for the winter, it being a daily driver and occasional snow plow.

I also enlarged my throttle pedal to help with heel-toeing. I'll try to find some pics of that also. My first attempt was too big but my second works pretty good.

One observation on heel-toeing though. I have FFS set to 4250 so that's all I get when I blip (or stand on) the throttle between shifts, and when you're downshifting into a corner your revs should be higher than that a lot of the time.

[shamie]

Duct photos:

[shamie]

Gas pedal pics (stock, too big, just right);

[aackthpt]

Originally Posted by shamie Gas pedal pics (stock, too big, just right);

Whoa. Want. Did you make a drawing or a CAD model? I imagine I could have FirstCut make this, and that would be awesome. I think you should consider giving the design to DM or AP so others can buy them too.

[GroceryGtr]

I was going to comment how the pedals are already the perfect gap for heal toeing(probably my favorite out of all the cars I drive), but then I saw the pic of the gap on the 3s and realized you guys don't have the huge kickout for the xfercase that pushes our pedals closer together. I can brake and blip the throttle without even trying. That being said HT is def an art refined over years of messing it up.

For the brake ducts to get the full effect you need to connect that hose to a backing plate. Not saying it won't help in its current form, but the cooling will be greatly diminished.

[shamie]

Connecting to the backing plate would be nice, just not very feasible with our set-up. I have trimmed the backing plate some right below the caliper.

The caliper is in front right were the hose needs to be. If you route the hose to the rear you've got to deal with navigating the axle.

One of my goals was to just see if running the hoses would work. It does so the next step (for next season) will be to work on the inlets and outlets to make them more effective. Since I never have braking (cooling) issues this was just a "nice to have" that I did when I was opening up my grill for more airflow through the radiator.

[ChaunceyM]

@shamie;, any chance you can get some more pictures of the full duct routing? I half-assed some ducts after consistently boiling fluid and found it tricky to route the 3" hose without rubbing something. I was also trying to get to the backside, which means going over/under/around the axle.
I've got 2" hoses that I'm to mock up as soon as I get a free weekend. I'll need a 3"-2" reducer at the fog lights (which are a perfect 3" hole), but the smaller hose should fit b/t the LCA and axle. Hopefully I can just cut a 2" hole in the dust shield and mount it there so it blows directly to the middle of the rotor.

[shamie]

I'll see if I can get some time this weekend to get it on ramps and take the splash shield off for some pics.

Its pretty basic though;
Zip-tied to the fog light and then just wedged between the splash shields (lower and sides).
Zip-tied again at the back of the splash shields to the shields and then to the front of the LCAs.

I just couldn't see how to get 3" behind the axles - best of luck with the 2".

I have read that removing the brake dust shields does help considerably in cooling but does get brake dust on all the suspension components. I'm not to that commitment level yet.

[shamie]

@GroceryGtr If someone has connected a hose to a backing plate I'd love to see how they did it (so I can copy it).

@ChaunceyM here are the photos; the first shows the trimmed backing plate and the last you can see the attachment to the fog light bracket. The rest just show it stuffed in there. It doesn't seem to move or rub at all. The splash sheild (removed for pics) holds (wedges) it in place. I don't know why this forum insists on rotating the last 2 pics - sorry.

[Voltwings]

Originally Posted by shamie @GroceryGtr If someone has connected a hose to a backing plate I'd love to see how they did it (so I can copy it). @ChaunceyM here are the photos; the first shows the trimmed backing plate and the last you can see the attachment to the fog light bracket. The rest just show it stuffed in there. It doesn't seem to move or rub at all. The splash sheild (removed for pics) holds (wedges) it in place. I don't know why this forum insists on rotating the last 2 pics - sorry.

The caliper being on the front side does make duct routing difficult. I don't know how it is on the Gen 1 (which it looks like you have), but on the gen 2, the under tray terminates exactly at the front axle centerline. I ran my ducts from the grille down the (inside) edge of the under tray where there is TONS of room, then used a silicone 90* coupler (terrible for flow, I know) and made a straight shot to the caliper.

What I did was remove the backing plate and made an L out of sheet metal that bolted in its place. The L essentially cradled the duct hose and got it pointed more or less at the center of the ring. To protect the tie rods I just used some left over sheet metal and made little heat shields. This is not a very intensive project, this was just plate sheet from home depot and some basic sheet metal tools from harbor freight.

[GroceryGtr]

not that I'm aware of Shamie. It was more a best practice suggestion. I would think an enterprising individual could take the stock dustshield and modify it to work, but your method with definitely help.

Is that a chunk missing out of your rim on pic #1 ?

[shamie]

Good eye - you had me worried for a minute. No it's not a chunk, it's just tape residue from wheel weights and a shadow from the flash.

[shamie]

Any pics of your bracketry?

[Voltwings]

Originally Posted by shamie Any pics of your bracketry?

Maybe somewhere... i'll try to remember to look tonight. I actually think I've commented on this before, but are those GTS-AV rims in your avatar? I have those rims on my wife's mustang haha.

[shamie]

Yes they are GTS-AVs. They are my street wheels. I track on lighter 17s.

[shamie]

Just a piece of scrap aluminum and a drill press. I copied the hole placement off the stock pedal. Only 3 or 4 holes need exact placement (attachment screws and positioning "pin") I bent the curve with a 2x4 and a mallet. If DM offered something like this for $30-40 I would've bought it.