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Old 31st August 2010, 19:22   #16
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Quote:
Originally Posted by Shan2nu View Post
Find out what pads your car is running.

Another thing to note would be your braking points on the track. Where exactly were you braking on corners where you experienced fade and what was the max speed your car was hitting just before braking?
Its running OE pads, exact make I'm yet to find out.

I brake progressively, its got something to do with me being a bike guy.
I usually brake early (Just after 100 mts) . I was told that I might heat up the brakes more if I do so.

So this time I was braking on the 50Mts mark.

Its like 50 to 70% on (progessive) - then adjust Braking pressure till you slow down enough - off the brakes.

I was going pretty conservatively

nudged a bit more than 140 approaching C4
140 approaching C8

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Old 31st August 2010, 23:43   #17
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I think you're braking too late, which is why you feel the car isn't stopping.

During my fastest laps, i was braking at the 100mtr mark for C4 (150kmph) as well as C8 (145kmph). At C1, i would just lift off at 50mtrs (140kmph) and turn the car into the corner.

Next time try braking a bit early, enter the corner a bit slower and capitalize on the exit. This should fetch you better lap times and make for a safer track experience.

Shan2nu

Last edited by Shan2nu : 31st August 2010 at 23:47.
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Old 1st September 2010, 00:04   #18
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Quote:
i was braking at the 100mtr mark for C8 (145kmph)
Correction : it was 125mtrs for C8 (145kmph).

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Old 1st September 2010, 19:59   #19
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Quote:
Originally Posted by Shan2nu View Post
I think you're braking too late, which is why you feel the car isn't stopping.
Shan, last time around I was braking aroung the 100 mtrs mark. Same brake fade was there. So I tried braking late this time, still the same fade.

Agreed braking early is a bit more safe IMO. Afterall most of are in it for the fun and not for setting lap recodrs.

C1 I usually feather the brakes just as I approch the arch then turn in.
C1 is the corner I fear on the track.

EDIT : Brake issue is being sorted out. Car is now at the garage. I'll update as soon as I have one. Hopefully there is another pnp 3rd week of Sep to test it.

Last edited by yzfrj : 1st September 2010 at 20:00.
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Old 1st September 2010, 20:19   #20
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I think the real problem is, OEM brakes aren't meant to be used on the track!! Plus, the OHC Vtec has lousy drums at the back. As per the other recommendations, if I were you, an upgrade to performance brakes would be underway.

You might also want to change your alloy wheels. I'm not sure if the design of the OEM Vtec alloys is the best for airflow to the brakes. Possibly, a more suitable design in 15 / 16 inch size?
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Old 2nd September 2010, 11:16   #21
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Quote:
Originally Posted by yzfrj View Post
EDIT : Brake issue is being sorted out. Car is now at the garage. I'll update as soon as I have one. Hopefully there is another pnp 3rd week of Sep to test it.
What exactly is being done?

At the beginning there were a few doubts as to what it might be (green fade, air in lines, etc), but after you cleared them this sounds pretty much like straight forward pad-fade to me.

I think your best test would be to switch to a different make of pads on the track itself.


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Old 2nd September 2010, 14:33   #22
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One question, in an instance of brake fade, will double tapping the pedal give better bite than a single constant depress? The reason I am asking is that if one thinks of the logic behind ABS systems then can't the same be applied here, manually? It could give a fraction of a second for the brakes to cool and avoid lockup at the same time.
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Old 2nd September 2010, 15:29   #23
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sorry,what does the word 'c4' 'c5' c7 c8 mean?
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Old 2nd September 2010, 16:00   #24
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Quote:
Originally Posted by GTO View Post
You might also want to change your alloy wheels.
Again, I don't think the OEM Vtec alloy wheels allow sufficient airflow to the brakes, especially in such high-stress conditions. Which do you think will cool / feed more air to the brakes?

*Yikes* Brake fade / No Brakes - Cause and Solutions-img_3904.jpg

*Yikes* Brake fade / No Brakes - Cause and Solutions-000_0888.jpg

Quote:
Originally Posted by Rehaan View Post
this sounds pretty much like straight forward pad-fade to me.
Completely agree.

Stock brakes aren't built for this kind of use. Upgrade to performance parts is the only way forward. Looking forward to what yzfrj eventually did.

Quote:
Originally Posted by NOS Power View Post
The reason I am asking is that if one thinks of the logic behind ABS systems then can't the same be applied here, manually?
It is humanly impossible to press / release the brakes as quickly as an ABS system can.

Last edited by GTO : 2nd September 2010 at 16:01.
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Old 2nd September 2010, 16:07   #25
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Quote:
Originally Posted by GTO View Post
I think the real problem is, OEM brakes aren't meant to be used on the track!! Plus, the OHC Vtec has lousy drums at the back. As per the other recommendations, if I were you, an upgrade to performance brakes would be underway.
True. This is a case of pushing the limits of the OE brakes. I do agree.
The only thing is other Vtec's on the the track (last time and this time)
were doing ok. So I'm just trying to find the weak link that is causing the issue.

I have my eyes on a set of performance pads. (Hawk)
This was recommended by Raghav (Ignite) who is a friend of mine.

But first I want to find the cause, then will upgrade.

Quote:
Originally Posted by Rehaan View Post
What exactly is being done?

I think your best test would be to switch to a different make of pads on the track itself.
A full brake overhaul (to check if the calipers are ok and all that), flushing the system and changing the Fluid, scrub the pads (if its needed)

A set of pads will be there as a standby. Might even end up replacing it before the next track day.
Ideally changing the pads at the track is what I'd like to do. Availability of the mechanic and all that will be an issue. Its definitely being looked into as an option.

Quote:
Originally Posted by NOS Power View Post
One question, in an instance of brake fade, will double tapping the pedal give better bite than a single constant depress? The reason I am asking is that if one thinks of the logic behind ABS systems then can't the same be applied here, manually? It could give a fraction of a second for the brakes to cool and avoid lockup at the same time.
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.

EDIT :

Quote:
Originally Posted by charlesxie View Post
sorry,what does the word 'c4' 'c5' c7 c8 mean?
Its the corners on the MMSC Track
Please see the pic in this (*Yikes* Brake fade / No Brakes - Cause and Solutions) post

Quote:
Again, I don't think the OEM Vtec alloy wheels allow sufficient airflow to the brakes, especially in such high-stress conditions. Which do you think will cool / feed more air to the brakes?
Agreed to this too GTO.
I'll not be able to upgrade the Alloys, financial constraints + I Like the stock look.
But yes if I get a second hand (read : for less Vitamin M) set I just might.

Last edited by yzfrj : 2nd September 2010 at 16:19. Reason: Adding more info
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Old 2nd September 2010, 16:32   #26
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Quote:
Again, I don't think the OEM Vtec alloy wheels allow sufficient airflow to the brakes, especially in such high-stress conditions. Which do you think will cool / feed more air to the brakes?
That would depend on the aerodynamic properties of the car. There's a very good chance the air just flows around the outside of the wheels (for better streamline) and there would be more air hitting the brakes from the inner side of the wheel.

For best results, you would need an air duct to actually get sufficient cool air to the brakes (again from the inside of the wheel).

Like shown here :

Quote:
True. This is a case of pushing the limits of the OE brakes. I do agree.
The only thing is other Vtec's on the the track (last time and this time)
were doing ok. So I'm just trying to find the weak link that is causing the issue
Exactly, if the OE brakes were really that bad, all the VTECs with stock brakes should have experienced this. In my case, i had to use less pressure in order to avoid the wheels from locking up.

Shan2nu

Last edited by Shan2nu : 2nd September 2010 at 16:43.
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Old 2nd September 2010, 17:26   #27
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Quote:
Originally Posted by yzfrj View Post
The only thing is other Vtec's on the the track (last time and this time) were doing ok.
Maybe you were using the brakes a lot more? Also, good idea in getting the brake line bled.

Quote:
But yes if I get a second hand (read : for less Vitamin M) set I just might.
Get in touch with Avinash (the current owner of my Vtec). Since the Honda got totalled, you might just end up lucky.
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Old 2nd September 2010, 17:28   #28
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Quote:
Originally Posted by Shan2nu View Post
There's a very good chance the air just flows around the outside of the wheels
I agree with this in general.
Its very hard to tell what design of wheel will provide better cooling when in motion just by looking at it. This also depends on airflow of each model of car.

Another question is how much cooling happens directly on the brakes due to airflow VS via transferred heat to the wheels, which are then air cooled.

Other wheel-related factors that could indirectly ad to the cooling of the discs are :
1) Mass of the wheel -- since it soaks up the heat thats transferred from the discs.
2) Exposed surface area of the wheel, since in essence it acts like one big heat-sink. The more surface area the wheel has, the more the air cools the wheel, allowing it to draw further heat from the discs. (Though this has its own set of complications when the wheels are in motion!)


Quote:
Originally Posted by Shan2nu View Post
Exactly, if the OE brakes were really that bad, all the VTECs with stock brakes should have experienced this.
This changes from OEM pad supplier to supplier -- but yes, we can assume that in general theres nothing majorly wrong with the system in general (ala fortuner). Who knows, even with the same supplier, it could just be a batch of poorly made pads?

cya
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Last edited by Rehaan : 2nd September 2010 at 17:33.
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Old 2nd September 2010, 17:38   #29
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Hi,

If I were you I would invest in drilled rotors and a set of aftermarket pads. The drilled rotors will dissipate the heat faster thereby reducing the fade.

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Old 2nd September 2010, 18:04   #30
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Quote:
Originally Posted by GTO View Post
Maybe you were using the brakes a lot more? Also, good idea in getting the brake line bled.
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.

Quote:
Get in touch with Avinash (the current owner of my Vtec). Since the Honda got totalled, you might just end up lucky.
Thank you. Will do that.

Quote:
Originally Posted by Rehaan View Post
This changes from OEM pad supplier to supplier -- but yes, we can assume that in general theres nothing majorly wrong with the system in general (ala fortuner). Who knows, even with the same supplier, it could just be a batch of poorly made pads?
Yes. This could be the case.

Quote:
Originally Posted by viper View Post
If I were you I would invest in drilled rotors and a set of aftermarket pads. The drilled rotors will dissipate the heat faster thereby reducing the fade.
Thank you. Can you give more details please.

1) Any specific models that can go with the OHC ?
2) Is it a "bolt on" or will this mean some modifications ?
3) Where to source it from ?
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