SLOTTED BRAKES.....12 or 6 slots

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Postby TRDmod » Fri Mar 25, 2005 1:04 am

hendce why i made it clear i wasnt deluding myself, but, therotically it should help when i am workign the brakes hardcore....so ill see when i go to puke
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Postby Mr Revhead » Fri Mar 25, 2005 1:38 am

Me - "I push very, very hard on the pedal!"


:lol: :lol:



is this really that hard to comprehend??? its there in plain english.....
try READING the info... and UNDERSTANDING it.. think about whats being said, process it inside your head.... its not hard :roll:
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Re: m

Postby vvega » Fri Mar 25, 2005 8:42 am

TRDmod wrote:hendce why i made it clear i wasnt deluding myself, but, therotically it should help when i am workign the brakes hardcore....so ill see when i go to puke


tell you what ill see what i can do about getting some stock good disc's for your car

thne you can do a few laps change ya disc's and tri again this is the only way to truely deside on brake force

we also have a braking force meter we can use to give documentation to support the finding ethier way :D

dont take what has been said as anything negative aganst you I myself will probably buy slotted rotors when it comes to fitting them to my racecar .. but i dont consider them to inprove my road braking at all :D
im still quite sure that ra 1 toyo's will give give me my greatest braking improvement


v
Last edited by vvega on Fri Mar 25, 2005 8:52 am, edited 1 time in total.
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Postby GT4 20 » Fri Mar 25, 2005 8:43 am

Adamal wrote:Exactly what gas is inbetween the rotor and the pad here? :? We're not talking about 'air' are we? Cause thats dispersed easily enough isn't it?


As much as I hate to agree with Robo.... on anything that he has mentioned so far, he is actually correct on this one.
Due to the compounds used in pads and the bonding agents used, when subjected to high levels of heat, they do actually produce a gas which can become 'trapped' between the pad and rotor. This is why slotted rotors can help as they allow the gas to escape.
However, my understanding is that this was more of a problem with the old asbestos type pads and is not really an issue if the pads are bedded in properly in the first place.
If they are bedded in properly, then the likelyhood is that for normal roda use, you are unlikely to get the pads hot enough to warrant the requirement for slotted rotors. Much more likely to be needed on the circuit or for legal fast road use - such as a hillclimb etc.
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Postby vvega » Fri Mar 25, 2005 8:56 am

GT4 20 wrote:
Adamal wrote:Exactly what gas is inbetween the rotor and the pad here? :? We're not talking about 'air' are we? Cause thats dispersed easily enough isn't it?


However, my understanding is that this was more of a problem with the old asbestos type pads and is not really an issue if the pads are bedded in properly in the first place.
If they are bedded in properly, then the likelyhood is that for normal roda use, you are unlikely to get the pads hot enough to warrant the requirement for slotted rotors. Much more likely to be needed on the circuit or for legal fast road use - such as a hillclimb etc.
Gary


really says it all

thanks for that gary
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Postby pc » Fri Mar 25, 2005 11:22 am

I have seen what I assume to be a 'gassing' problem once.
My sister's GTI-R racecar had some new repco ferrodo GP2 brake pads on it and after lots of heavy braking there was a tremendous shudder that felt like it was going to throw the car off the road. The braking was fine if not pushed too hard though.
We changed the pads to the Lucas ones that repco sell and it was fine after that.
I haven't had this problem on my FXGT myself and I have the GP2 pads, but they do get awful hot and appear to burn the rotors. Maybe it's just a very 'gasy' pad?
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Postby Stealer Of Souls » Tue Mar 29, 2005 9:44 am

I'm pretty sure I read something about that "burnt" look in this article...



http://www.stoptech.com/whitepapers/war ... s_myth.htm
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Postby pc » Tue Mar 29, 2005 10:10 am

That's a good read. Looks like the shuddering may have been brake pad deposits on the disk... which would make sense, given that I can see the deposits on my car when using the same pads.
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Postby suberimakuri » Tue Mar 29, 2005 10:54 am

interesting that the point of "if you can lock the brakes then you need better tyres" was brought up.
too far back for me to bother looking who said it.

just to confirm, this person can't be for real?
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Postby Mr Revhead » Tue Mar 29, 2005 10:56 am

yes they are for real, and correct....

if you can lock the wheels easy... what use is extra braking force??
you have to improve the suspension and tyres to use the full potential of your brakes.

how ever there is brake fade to consider.....
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Postby suberimakuri » Tue Mar 29, 2005 11:05 am

heh... seems to me that most of the time the tyres lock because the pad has locked against the rotor..... not that you're slowing down too fast for the grip of the tyre.
Changing to better pads or bigger brakes will result in better stopping without the tyre locking

example, but in the opposite direction.
Top fuel dragstar running 4 sec 1/4 miles doesn't make front wheel slip.
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Postby Mr Revhead » Tue Mar 29, 2005 11:22 am

how do you think the pad locks??
maybe its because the retardation is greater the the grip of the tyre....
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Postby suberimakuri » Tue Mar 29, 2005 11:25 am

nope.

try running junk yard pads...... then go get some good mintex or similar.

wheel will lock with both, but it will lock first at a higher speed with the junkyard pads.
ie: junkyard pads won't slow you down as much before lock.


Same tires.

i tested this many times. :P
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Postby Mr Revhead » Tue Mar 29, 2005 11:30 am

certain pads will have better "feel" and others will be more grabby.... certainly some are more prone to locking, as in they will suddenly snatch. but only if they excede the grip available from the tyres. so it comes back to the tyres and suspension.

lets put it another way.... if your tyres "out grip" your pads, then your wheels wont lock.

bare in mind a lot of this discussion is simplified... theres lots of factors that determine brake performance.
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Postby suberimakuri » Tue Mar 29, 2005 11:36 am

cool, i agree with what you're saying in principal.

in practice, i've found that with brakes on my cars;
running better pads allows me to brake faster/harder before the tires/wheels lock up.

I'm talking about braking once, not multiple times, and i'm talking about keeping every other variable the same.... fluid, tires, shocks.
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Postby Mr Revhead » Tue Mar 29, 2005 11:41 am

yup, thats comes under
certain pads will have better "feel" and others will be more grabby.... certainly some are more prone to locking, as in they will suddenly snatch.


:D

its obvious the better pads have a better feel and more consistant action.
serves you right for being cheap and using 2nd hand pads! :wink:
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Postby suberimakuri » Tue Mar 29, 2005 12:14 pm

heh.. maybe heat causes the pads to "bind" to disc and lock?
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Postby 85AW20v » Tue Mar 29, 2005 12:54 pm

I had a flat tyre at a trackday once so put on a Firestone Enduro on the front left of the MR2 and still had the sticky Dunlops on the other three. Braking efficiency was markedly reduced on the front left with that tyre constantly locking and I also ended up in the kitty litter as I tried using my usual braking points. Lap times dropped about a 1.5 sec due to the Enduro and lack of grip when braking. It didn't make any difference having that tyre on through the esses at Taupo - the only 2 right hand turns on the track.

Karl - try it the other way round - same pads, different tyres. You might be surprised at how easy it is to lock budget tyres as opposed to performance or race tyres.
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Postby pc » Tue Mar 29, 2005 2:23 pm

nope.

try running junk yard pads...... then go get some good mintex or similar.

wheel will lock with both, but it will lock first at a higher speed with the junkyard pads.
ie: junkyard pads won't slow you down as much before lock.


Same tires.

i tested this many times.


Remember that better pads probably don't 'grab' as quickly as cheapies, i've found this. If you get better braking with better pads, but the cheap ones still lock up, it just means you pressed the brake pedel too quickly and it 'grabbed' before you allowed time for the weight to transfer onto the front wheels.
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Manfield - 1:24s
Taupo - Track1 1:53s (road tyres) - Track2 1:22s - Track3 48s (with esses) - Track4 1:58s
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Postby suberimakuri » Tue Mar 29, 2005 3:27 pm

interesting....
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