CO track thread

[Bishop]

Yeah, hopefully Chris will say something, or Eric since he did a brake overhaul on his track car. I've never had my pedal go all the way to the floor at HPR or even autocrossing.... Something's not working right.

[Eric]

that doesn't sound right! are you engaging ABS at all when braking?

how much fluid have your bleed through the system?

You might need to bench bleed the master cylinder, sometimes an airpocket won't escape the MC with just pumping.

what is your bleeding technique?

[blefevre]

Roland did the bleeding so he will let you know. ABS activated a very little bit only a few times. Which I thought was weird, with snow tires it should go off pretty easily.

[Roland H]

I need more help with brakes.

I went and made an attempt at bedding in the brakes again. Also just to make sure everything works as expected. Here is what happened.

Brakes faded very quickly. I was doing repeats of 60-10 or so at 80% braking force, some at 100%. Within a short time I was able to get to the point where my pedal was on the floor nearly every attempt. Of course I wasn't pushing the brakes at this point either though.

Questions:
Should the pedal be getting that soft in that short of time? Is that the effects of the street pads or is my MC screwed or air in the lines? Once they cooled again I had a pretty firm pedal like I do under normal driving.

Specs:
Axxis ULT
New lines, calipers, fluid
Super awesome snow tires

Should I be concerned about the pedal going to the floor that quickly? I can't really say it increased my confidence to enjoy a track day, lol.

Sounds what my car does after a really hard bleed session with street or race pads. Never faded on the track, but I have certainly faded them in the canyons or on bleeding runs, and that's in the M3 which has considerably more braking force.

Yeah, hopefully Chris will say something, or Eric since he did a brake overhaul on his track car. I've never had my pedal go all the way to the floor at HPR or even autocrossing.... Something's not working right.

Going to wait for Chris to chime in too, but I think he's fine if the pedal is going back to firm once they cool. It's likely just the pads... Axis ULTs fade pretty easy in my experience with the volvo.

Roland did the bleeding so he will let you know. ABS activated a very little bit only a few times. Which I thought was weird, with snow tires it should go off pretty easily.

Power bleeder and manual bleed were both used.

I'll definitely bleed it again for you if it needs it or it's what you want, I guarantee the work.

[fsmtnbiker]

If the brake pedal is going to the floor you are either boiling the fluid or you have a line somewhere that is bulging/failing... Or there's still air in the system.

Also, I hate axxis ultimates. I'd rather make brake pads out of wood than use them.

If you're getting fade that bad with a basically new braking system, I would inspect all the wheel bearings very closely and also go for a drive, 15-20 mins at speed, and then stop and feel each wheel and make sure one isn't considerably hotter than the rest. If one is noticeably hotter, this points to a dragging brake due to either air in the system, a sticky/faulty caliper, or a bad wheel bearing.

[blefevre]

I will check the wheel heat and see if anything is different.

Is there a chance that the awful braking is due to the axxis ultimates?

I think this is leading to a little bit of air in the system somewhere and bad pads.

[blefevre]

Is there anywhere to get HP+ for less then $200?

[Bishop]

I'll doube check the link when I get home but try raceshopper.com. It's a weird site and you have to submit a request for a quote but they're usually good. I think I was quoted 390 shipped for a new set of rotors front and rear and a set of ht10s to match the rotors

[blefevre]

Alright, I will give it a shot.

[Roland H]

Does Tim still have the turner pads?

[blefevre]

I'll doube check the link when I get home but try raceshopper.com. It's a weird site and you have to submit a request for a quote but they're usually good. I think I was quoted 390 shipped for a new set of rotors front and rear and a set of ht10s to match the rotors

$176 shipped for all four sides. Not too bad. I am still not sure if I want to resort to new pads/rotors for this braking. Maybe the soft pedal is in my head too. ABS should be doing more work though.

[Bimmerman325i]

$176 shipped for all four sides. Not too bad. I am still not sure if I want to resort to new pads/rotors for this braking. Maybe the soft pedal is in my head too. ABS should be doing more work though.

I'm willing to bet it's air in the lines or bulging lines (i.e. dead ones), not anything to do with pad compressibility. New pads are good, but I don't think it will solve your problem.

Could be air in the ABS system too. Do a bunch of hard stops to engage ABS to cycle it a bunch, then rebleed. Might fix it.

[blefevre]

Could be air in the ABS system too. Do a bunch of hard stops to engage ABS to cycle it a bunch, then rebleed. Might fix it.

This might be it.

The lines are new SS lines, I don't think there are any other rubber lines are there? The pedal is nice and stiff for DD driving.

[Bimmerman325i]

This might be it.

The lines are new SS lines, I don't think there are any other rubber lines are there? The pedal is nice and stiff for DD driving.

Did all six SS lines get installed? The inner two are, quite possibly, more annoying to install than dropping my transmission the three times it took to fix it. How I hate those lines......

Only other rubber line would be the clutch line, but that shouldn't be an issue. You could have a bad SS line, or it isn't tightened enough/was tightened too much, or something closer to the reservoir and master is bad.

If ABS isn't engaging as it should though, I'd check that (and your wheel speed sensors/ring).

[blefevre]

All 6 got installed. ABS is engaging, just not as much as I would expect it to.