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Old 2nd September 2010, 18:07   #31
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Originally Posted by yzfrj View Post
I have my eyes on a set of performance pads. (Hawk)
This was recommended by Raghav (Ignite) who is a friend of mine.
IIRC, couple guys incl. Nitrous are already running these in their cars.

How old is your car?

A properly designed cooling duct will also help a lot.
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Old 2nd September 2010, 18:33   #32
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Originally Posted by Mpower View Post
IIRC, couple guys incl. Nitrous are already running these in their cars.
I was told these are pretty good. I did't know about nitrous having them.
Let me ask him then, thank you.

Quote:
How old is your car?
Got it second hand last April

2003
665xxKms as of yesterday

Rotors were faced at 64600Kms, with new OE pads.

Quote:
A properly designed cooling duct will also help a lot.
Hmm.. has anyone seen that thing in Discovery (or was it Nat geo ?) when they were doing all the things that lead to the New Corvette Z06.

It has a brake cooling duct,(they were testing it on the German Autobahn ) changing the diameter of that drastically increased the heat (while reducing the overall drag). So they reverted back to the original size (and decided the increased drag is ok). I don't think we should be messing around that, IMO its a bit too complex for a jugaad job.

I'm not saying directing air flow will not help keeping it cool. But it will bring in certain unknowns into the overall equation with it.

I have a good example for it. A friend was using a CAI. He was happy with the car and all was well. One fine (after more than a year with the CAI) day he was having some issue (unrelated to the CAI in question) and to trouble shoot hooked up and OBD scanner. Then he accidentally noticed the engine is actually getting "hot" air with the CAI. The entire setup was chucked and it was redone, then verified with the scanner.
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Old 2nd September 2010, 19:13   #33
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Hi,

There are numerous places from where you can get rotors. Its a question of knowing what fits the car.

See this link for eg. This fits the OHC perfectly(15" rims and above only).

Roto tech EP-3295-L Roto-Tech Acura/Honda Brake Rotors

or see this and find the part no.

Super GT Ltd.

Viper
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Old 2nd September 2010, 20:13   #34
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Well not this time around. I was using the brakes a lot less (read : hard and shorter). Last time around I was more progressive with the pedal.

Usually I'm very gentle on the brakes (especially on the road). I was told this is not a good thing to do on track (read : you end up using the brakes for too long = more heat = more chance for fade.). Progressive braking = Faster cornering speed that does't mean a faster lap.
How did the 2 braking techniques affect your lap times? What was your best lap last time and this time?

It would be good to note such things down before you go in for a brake upgrade, that will tell you how much it has helped.

Shan2nu
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Old 2nd September 2010, 20:19   #35
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Post Update

I've got updated about an hour back that there is a "jammed" caliper (Left side). I don't think this is what triggered the fade.

There was a very mild rubbing sound when turning hard right and reversing.
This cropped up after the track day, when I parked up at Muskat Bakery. Then it went away only to surface 2 days back in my office parking lot.

I suspected something was wrong and hence the opening up the brakes.
Test drive confirmed the was something fishy with the brakes.

Strangely car was not pulling to one side (even under braking with no hands on the wheel). Only a "squealing" sound (a tad too loud - like the rally cars from both sides, a bit loud on the left) under braking. There was hint of a mild squealing (while driving) from the left after the "rubbing sound" became permanent. The very next car was left at the garage.

EDIT :

Quote:
Originally Posted by Shan2nu View Post
How did the 2 braking techniques affect your lap times? What was your best lap last time and this time?
It would be good to note such things down before you go in for a brake upgrade, that will tell you how much it has helped.
Shan2nu
This might sound strange. I have not timed myself on the vtec.
2:31.852 (with proper timing equipment) was the time I did on my carb Zen.

Link from that track day

So I'm guesstimating I might be doing 2:25's - 2:30's given the fact that vtec is 2 times as powerful.
I'm yet to push it as I'm not comfortable with the vtec as I was with my zen.

How I miss the zen on track. Should't have sold it :(

Last edited by yzfrj : 2nd September 2010 at 20:26.
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Old 3rd September 2010, 10:38   #36
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Quote:
Originally Posted by yzfrj View Post
The idea is to "pump" the brakes. That will mean you are going On/Off. This is exactly what an ABS does, but say close to 50 times a second.

And if this is on public roads, do down shift as quickly as possible.
Track you can always run out of road with no after effects.
Yes I meant, pumping the brakes. Even on track can't this be done? Reason I am asking is that when we talk about heat dissipation and all that, if a pad is constantly pressed then it does not have an option to dissipate heat, so what if the brake pedal is pumped to allow the pads to dissipate heat and debris if any. The brakes will bite back as new, rather than give a diminishing brake bite.

Its a simple logic, like when we want to lift a heavy object, on first try when we find it too heavy do we keep lifting or do we release pressure and then try and lift up again with greater strength.

In rallying we do this regularly, as it avoids lockup and gives instant bite everytime we depress. Also it leads to lesser fade.

Coming back to your brake fade issue, check the brake lines. Get them cleaned or replaced if you find them dirty.
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Old 3rd September 2010, 16:46   #37
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Lightbulb More updates, more theory and the solution

Quote:
Originally Posted by NOS Power View Post
Yes I meant, pumping the brakes. Even on track can't this be done?
Ideally on a smooth surface there is no need to pump the brakes.
IMO this should be used as a way to recover form a fade and is certainly not the solution.

More updates...!


First the bad news.

We are not able to isolate the cause. There are multiple failures and we can only speculate as to what caused what.

Possible cause

As I've updated before there is a jammed caliper (left).
This was not there when the brakes were checked couple of days before the track day.

The caliper might have failed on the track (it would have eventually, there are too many unknowns here as I don't know if anything was done (or not done) by the previous owner. Considering the age of the car this is to be expected I guess).

The failure might have been triggered due to excessive heat. Excessive heat might be due to

- Pad fade or
- Fluid fade (possible but unlikely)

So natural thing was to stomp on harder. Which made it heat up more and made it worse.

Pad fade might have due to improper bedding in

Rotors were faced + new pads + 100% city driving = More chance of improper bedding in.

The jammed caliper had made the contact patch about 50% for the left pads. So this caused to improper heat build up and uneven wear on the pads. Pads are ruined now. Thankfully rotors are ok.

Blown Caliper
*Yikes* Brake fade / No Brakes - Cause and Solutions-dsc03081.jpg

Rotor - The shiny area was the "contact" patch.
*Yikes* Brake fade / No Brakes - Cause and Solutions-dsc03082.jpg

Screwed up pad - See the uneven wear on the bottom
*Yikes* Brake fade / No Brakes - Cause and Solutions-dsc03083.jpg

Back side of the pad
*Yikes* Brake fade / No Brakes - Cause and Solutions-dsc03084.jpg

Rotor (Right Side) - this is how it should be
*Yikes* Brake fade / No Brakes - Cause and Solutions-dsc03086.jpg


Plan of Action

Complete brake overhaul
Flush the system and new DOT4
Change Calipers both side
Hawk Performance Ceramic Pads

*Yikes* Brake fade / No Brakes - Cause and Solutions-dsc03087.jpg

*Yikes* Brake fade / No Brakes - Cause and Solutions-dsc03088.jpg

*Yikes* Brake fade / No Brakes - Cause and Solutions-dsc03089.jpg

*Yikes* Brake fade / No Brakes - Cause and Solutions-dsc03090.jpg

*Yikes* Brake fade / No Brakes - Cause and Solutions-dsc03091.jpg

Last edited by yzfrj : 3rd September 2010 at 16:49.
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Old 3rd September 2010, 16:54   #38
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I think if the brake is servo assisted it should not be pumped but applied steadily. I remember reading something to this effect in the Alto owner's manual.
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Old 3rd September 2010, 17:22   #39
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Quote:
Originally Posted by yzfrj View Post
Plan of Action

Complete brake overhaul
Flush the system and new DOT4
Change Calipers both side
Hawk Performance Ceramic Pads
What's the estimate for the calipers? You might as well spend a little more and buy a set of aftermarket dual pison calipers like Wilwood. I think Jitu has it on his OHC.

Stock calipers can also be rebuilt using a rebuild kit that consists of a piston gasket.
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Old 3rd September 2010, 18:02   #40
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Originally Posted by Mpower View Post
Stock calipers can also be rebuilt using a rebuild kit that consists of a piston gasket.
My bad. I think this is what is being done on both sides.
Wilwood is too expensive for me.
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Old 3rd September 2010, 18:20   #41
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I was running EBC Green Stuff.
The Hawks are very good. hirevbg runs it in his Dzire.

My EBCs took ~500kms to totally bed in and work to their full potential.
Since you're gonna get them fitted on the ECR. Use the road and get them bedded-in perfectly.
Get Raghav to help you with the bed-in.
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Old 3rd September 2010, 19:09   #42
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Originally Posted by nitrous View Post
I was running EBC Green Stuff.
The Hawks are very good. hirevbg runs it in his Dzire.

My EBCs took ~500kms to totally bed in and work to their full potential.
Since you're gonna get them fitted on the ECR. Use the road and get them bedded-in perfectly.
Get Raghav to help you with the bed-in.
M,
The bed-in is pretty simple as per Hawk website

Quote:
1. After installing new brake pads, make 6 to 10 stops from approximately 30-35 mph applying moderate pressure.
2. Make an additional 2 to 3 hard stops from approximately 40 to 45 mph.
3. DO NOT DRAG BRAKES!
4. Allow 15 minutes for brake system to cool down.
5. After step 4 your new pads are ready for use.
Yes planning to get it down with Raghav's help.
I'd rather use the ECR > Sholinganallur connection road (straight and much less traffic), than ECR.
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Old 3rd September 2010, 20:17   #43
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@YZFRJ,
Could you post pictures of the other side of the rotor please.

Also, when you were getting the rubbing sounds, did you try jacking up the wheel, prying apart the pads, and then rotate the wheel by hand? If so, what did you observe?

Regards
Sutripta
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Old 3rd September 2010, 20:30   #44
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Quote:
Originally Posted by Sutripta View Post
@YZFRJ,
Could you post pictures of the other side of the rotor please.

Also, when you were getting the rubbing sounds, did you try jacking up the wheel, prying apart the pads, and then rotate the wheel by hand? If so, what did you observe?
I'm not sure if I'll be get that pic for you. All the stuff should have been fitted back on the car by now. If its not I'll get it for you once I go there tomorrow.

Brakes were not "binding" as expected and the wheel was rotating pretty freely. The rubbing sound was heard when turning full lock to the right and reversing. Other than that there was a mild squeal from the left. (this is pretty normal after a track day in my experience)
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Old 3rd September 2010, 21:03   #45
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^^^
Hi,
Brake squeal is a subject of the black arts, and not science/ engineering - eradicating requires the services of an exorcist! However, other noises should have more logical and obvious reasons. So hard right lock, jack up wheel, reverse rotate by hand. Observations? Wild thought:- are the wheel bearings OK?

What you described initially is classic brake fade. But bearings with play, untrue rotors etc coupled with hard usage will magnify the effects of knockoff. Just a thought.

Regards
Sutripta
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