Heres the situation. I ran limerock again this year in my hatch
92 hatch w/swap
konis front and rear
stock brakes up front
gsrs in rear (i think)
XP8 pads up front
stock pads in read
Dot 4 fluid in the lines

Now my question is this...some time durring my 2nd session I noticed them getting *softer*. Durring my 3rd I really had to lay on them at the end of the straight, and several times i had to carry alot of braking into a few turns which I didnt like. After that session I called it a day.

What should I do???
For refrence my instructor was very pleased with my braking so im *hoping* its not me abusing them...

Would just some simple ducting fix my problem or maybe running some real pads in the rear?? I kinda wanna avoid bigger brakes but will go that route if need be.

Thanks guys...

 

bleed the brakes.

You shoulda come over to us when you had this issue, we had to bleed the CW R's "Gregs" brakes because of the exact same issue after his 2nd or 3rd session.

 

Duct them. Your rotors are a heat sink and obviously you are getting them hotter than your braking system likes which of course is boiling your brake fluid. Just a reminder to do a full cool down lap without hitting the brakes at all. I try coming into the pit and the paddock without hitting the brakes. A lot of time it is the heat soaking of the calipers once you stop that gives you the mushy pedal.

Go buy some temp resistant hose, get some military spec zip ties and make some brake ducts blowing on your rotors. If you can cut those damn dust shields off too to get the duct hose to the rotor but that is a bitch with the knuckle on the car.

Oh yeah, yes, bleed them. But that is an "after the fact" thing. Ducts help prevent or lessen the problem in the first place.

Barry H.

 

ok i didnt think about bleeding the fluid..

Cool ill duct them up over the winter...thanks guys

 

Each time brake fluid boils, the boiling point is lower. Higher boiling point fluid may be enough to simply not boil at all or at the least has more room for the boiling point to get lower while still having some function left. Bleeding it between sessions gets the boiled fluid out of the calipers and replaces it with fresher fliud that is back to having a higher boiling point. There are a number of fluids that will hold up much better to track temps than what you can get at the auto parts store. There are lots of opinions as to what works best. I buy Performance Friction Z-Rated fluid by the case every couple of years and find it works well at a reasonable cost.

 

While I agree with you Barry, I think there is a bit more to why exactly he may have bioled the fluid at Limerock which is Not an extreme braking track.

All of what you suggested is correct but I think working on braking itself, using them less and compressing the zones, the cooling down before pitting then cooling down a few laps around the paddock and making sure to not use the brakes much if at all during this cooling down. Clearly he has pads and fluid that should be sufficient and ducting is a great idea but there might be more to it than ducting alone will solve.

I am the self proclaimed King of brake issues. I have tried more mechanical things to solve thie mushy pedal than maybe I should have.

Almost 3 years after the first mushy pedal issue and it turns out it was more the guy behind the wheel than anything other than a good bleed/flush could solve.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by SICK obvious BOY &raquo;</TD></TR><TR><TD CLASS="quote">
Now my question is this...some time durring my 2nd session I noticed them getting *softer*. Durring my 3rd I really had to lay on them at the end of the straight, and several times i had to carry alot of braking into a few turns which I didnt like. After that session I called it a day.
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You didn't comment on the feedback you were getting from the pedal. Did the brake pedal get "longer", or did you need to push "harder" to get the same effect. the difference is important in diagnosing what is wrong.

Also did the problem get consistently worse throughout the day? Did it get bad right away and stay bad? Did it recover between sessions?

Remember when diagnosing that it might not just be heat or boiled fluid, but that pad compounds can deteriorate to crap, even if it looks like you have material, they can glaze, and a number other things not related to the hydraulics.

pm civicrr for some suggestions and good pad compounds for your type of driving. oh yeah and duct the brake

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote &raquo;</TD></TR><TR><TD CLASS="quote">92 hatch w/swap.....stock brakes up front
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Check to see if you've bent the inner brake pad. Swap+stock brakes = HIGH brake temps. Bent pads give a horribly spongy soft pedal.

If you haven't already, remove the splash shield and relocate them to the nearest garbage can....

 

ducting would not have been the answer. the rotor would cool too fast and crack with the outside temp being in the 40s. i suggest removing the splas shields for sure and mayve upgrading to something larger (10.3 or 11"). but, as was mentioned already, make sure its not a driver issue first.
next time feel free to ask any of the other honda guys (myself in the white ef hatch, the 3rd gen h5 race car or any of the other r-speed clowns)

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Lo-Buck EF &raquo;</TD></TR><TR><TD CLASS="quote"> or any of the other r-speed clowns) </TD></TR></TABLE>

I resemble that remark Duh...

 

What brand fluid are you running?

Remember that brake fluid is hydro-absorbent, (obviously because of the dry/wet boiling point) so it will pull water out of the air, even just sitting in a nice sealing resevior, or just sitting for long periods of time (years) in an unopened bottle, or sitting for short periods of time in an opened bottle (months).

Some people I know replace the fluid after every race, some do it a few times a season but I would recomend at the very least once per season, preferably at the begining, but that might not be frequently enough.

And when you boil the fluid air does get introduced to it.

Brake ducts are your friends.

Chris - Who does not have duct's and thinks he might of boiled some Motul at Beaver this season.

 

guys thanks for all the response

I dont have any shields i removed those bad boys
fluid was valvoline dot 4 (changed 2 days before the event)


<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by MaddMatt &raquo;</TD></TR><TR><TD CLASS="quote">Check to see if you've bent the inner brake pad. Swap+stock brakes = HIGH brake temps. Bent pads give a horribly spongy soft pedal.

If you haven't already, remove the splash shield and relocate them to the nearest garbage can....</TD></TR></TABLE>

Damn I total forgot about that..when I ordered these bads the guys at Carbotech told me to check for that. They stated there was two versions for my car and the 2nd was out of stock..the 2nd had a thicker backing plate..


The pedal feel got loonnnggeeerrr yet also was easier to push down..It didnt feel like it was doing anything until below the halfway point when it usually felt like i had engagement around 1/4 of the way down

 

Get some 11" front brakes - fastbrakes sells a nice kit. Run xp8's up front with motul rb600 fluid - problem solved

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by .RJ &raquo;</TD></TR><TR><TD CLASS="quote">Get some 11" front brakes - fastbrakes sells a nice kit. Run xp8's up front with motul rb600 fluid - problem solved </TD></TR></TABLE> Agreed!!

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by SICK obvious BOY &raquo;</TD></TR><TR><TD CLASS="quote">guys thanks for all the response

I dont have any shields i removed those bad boys
fluid was valvoline dot 4 (changed 2 days before the event)


Damn I total forgot about that..when I ordered these bads the guys at Carbotech told me to check for that. They stated there was two versions for my car and the 2nd was out of stock..the 2nd had a thicker backing plate..


The pedal feel got loonnnggeeerrr yet also was easier to push down..It didnt feel like it was doing anything until below the halfway point when it usually felt like i had engagement around 1/4 of the way down</TD></TR></TABLE>

with the swap, the fastbrakes kit is probably in order, but might wanna try the RBF600 first.

i've yet to boil the stuff, and it sounds like you're getting fluid fade. also, cut the heat shields off and check to see if your pads aren't glazed, just in case.

if that doesn't work, call up FB.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote &raquo;</TD></TR><TR><TD CLASS="quote">Damn I total forgot about that..when I ordered these bads the guys at Carbotech told me to check for that. They stated there was two versions for my car and the 2nd was out of stock..the 2nd had a thicker backing plate..

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Actually, there's *THREE* versions of that plate with various thicknesses. We don't even use the thinnest one anymore for any race materials. You likely got the middle one (still significantly thicker than the thinnest one). If you bent those, bigger brakes might need to happen. At a minimum the 10.3" Integra brakes. But might as well get the 11" Fastbrakes.

For the record I use the Ford fluid. Cheap, readily availible, and I haven't boiled it yet. Fresh Valvoline should have been OK though.....

 

Why is it that I am always reading about someone having brake problems on the track. Is it lack of maintenance? Poor braking habits?......I have a stock GSR brake setup with steel braided lines, a good race pad, good rotors, and ATE super blue brake fluid (this is what was in the car when I got it so I continue to use it) and I do have brake ducts to each front rotor......I bleed the brakes before every race without fail, I don't run the pads down to nothing, I replace the rotors whenever I see the start of heat related cracks in them and I inspect all the nuts and bolts related to the brake system before every race (none of this is done at the track).......I haven't had a brake problem in my last 2 years of racing ...some 30-35 races.......(knocking on wood..)

You shouldn't be on any race track if your brakes are questionable at all !!!!



Modified by Maxx44 at 11:21 AM 11/12/2005

 

ALL of these are good suggestions.

Valvoline and Ford are okay brake fluids, but there are others with significantly higher boiling points. You can find a recent and reasonably complete list of fluids and their boiling points in this previous topic.

Regarding those splash shields - what I did with my car is, I kept them on, but cut a hole in them and welded a flange to the hole. That made the perfect mounting point for the hub end of my cooling ducts.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Maxx44 &raquo;</TD></TR><TR><TD CLASS="quote"> I replace the rotors whenever I see the start of heat related cracks in them </TD></TR></TABLE>
if that were the case, i'd be replacing rotors after every other session. i let those smakk surface cracks go. once they get deep and start heading toward the edge of the rotor, then its time to change them.

 

Me too. When I see spider web type cracks, I just keep a closer eye on them (and make sure I bring spares to the track). They gradually worsen with track use. When you can see any individual cracks about 1/2" long, that's about when you can feel them with the edge of your fingernail (wait until they're cold please ), and that's when I replace the rotors.

Keep in mind that these cracks fill in when you're out on the track, as the rotors expand. They will be wider, and more visible, and you're more likely to feel them when driving, after the car comes back in and has a chance to cool down for a while.

 

I am wondering if getting Stainless Steel Braided lines would help as well.

You could also try Ford's Heavty Duty fluid which is about 50 degrees less than Motuls RbF600, but it is more Hydroscopic and has a lower wet boiloing point at around 250 degrees, which shouldn't be a problem if you bleed your brakes regularly.

Also the Ford heavy duty fluid I got for about 2 bucks a bottle which is 12 FL oz.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Pat McGroin &raquo;</TD></TR><TR><TD CLASS="quote">I am wondering if getting Stainless Steel Braided lines would help as well.</TD></TR></TABLE>

Not in this case.

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote &raquo;</TD></TR><TR><TD CLASS="quote">You could also try Ford's Heavty Duty fluid which is about 50 degrees less than Motuls RbF600, but it is more Hydroscopic and has a lower wet boiloing point at around 250 degrees, which shouldn't be a problem if you bleed your brakes regularly</TD></TR></TABLE>

The big benefit for me to using the Motul stuff is that I never have to touch it or worry about it. I flush the system once a year and never bleed it, and it has never faded, boiled, etc on me - and I've run brake pads through the backing plates, cracked rotors, destroyed calipers....

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by obviousBOY &raquo;</TD></TR><TR><TD CLASS="quote">The pedal feel got loonnnggeeerrr yet also was easier to push down..It didnt feel like it was doing anything until below the halfway point when it usually felt like i had engagement around 1/4 of the way down
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zombie thread, back from the dead..

i'm having this exact same problem.. suddenly appeared when getting the car ready.. no amount of bleeding has solved the problem, nor a MC change.. I'd never heard of bending the pads before and I'm wondering if I haven't done that now.. I have Spec VR's though, not Carbotech pads..?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by mstewar &raquo;</TD></TR><TR><TD CLASS="quote">I'd never heard of bending the pads before and I'm wondering if I haven't done that now..</TD></TR></TABLE>

It's bedding, not bending. You can read about it here.

It's also worth noting that most pads fade the first or second session you get them really hot on a racetrack ("green pad fade"), but should not do so after that for the remaining life of the pad. This is normal.

 

Matt really mean bending.

I've seen this happen before mostly with single piston caliper. here is the picture from carbotech website