brake ducts for track duty


What if you have wheels with Toyo R888's on them and you have massive grip. You use, let's say, 282mm brakes with ITR calipers, Endless CCX pads. You can lock the weel up if you want and with R888's it's not a matter of a shortage of grip. How can other calipers make your car brake harder without blocking? It's still the tire that limits how hard you can brake then and not the caliper/pads/disc. The tire is blocking cause it has no more grip, not cause the caliper can't grip the disc harder or so. If I'm wrong, feel free to explain to me what I'm missing :)
 
With better tyres, you get improved braking efficiency too as the tyre wont lock up as easily.
The reason you're locking up in this case is your pads are snatching at the disk as they've run out of ability to slow the disk down and just grab. This is not good because you know a car will slow down quicker when the wheels are turning than locked up and skidding.
If you move the lever effect outwards, it uses less effort to slow the disk down that's rotating at the same speed, so you still have more effort available in reserve.
 
Not sure if I understand you. Are you saying that with better pads and calipers you can brake harder without locking up? Higher deceleration without locking?
 
Essentially yes. You will be able to slow down at the same rate using less effort if you have bigger diameter disks and/or a larger area of pressure on the back of the pad. You then have effort still available to slow the disk down because you haven't used it all to lock the disks up.
I'm trying to find a source for some pictures/maths to explain it better, but the bedroom walls needing sanding is getting in the way lol
 
Command thy woman to work :p But even if you use that extra effort, you will again run against the limitations of the tires right? That's the part I guess I'm not understanding :)
 
wow lots of replies....but i think this has turned into an argument over oem vs aftermarket brake setup and the difference in braking power vs tire grip. my essential concern is brakes fading and my tires fading. i am going to be upgrading the brake setup pretty soon whenever i have the $$ saved up. but while the brakes are out i want to see if a can modify/fabricate a duct into the backside of the rotor while the knuckles are off to make it so much easier than putting one in while its still on the car.

iceman said:
all ducting setups on eks are custom done, stuff is readily available from any motorsport shop (ducting/ties etc)
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i understand there isnt a brake duct kit out there for the 9s. thats why i asked for some pics to see how/what ppl bought for their ducts. so in turn, i could get an idea of how its done properly. i can just go out, buy the ducts, and try my best to fit it. but there would be no point of this forum. we suppose to share information on here and thats mainly why we're all here.
 
I was out on track on friday with my EK4, im running standard brake setup with OEM spec pads on rear and Carbotech pads up front and i didnt feel any brake fade for the whole day, have to say i was amazed at the Carbotechs and i will definitely be buying them again. Im running R888s
 
I think it's a cheap temporary partial solution that might give you some more time before fading kicks in. Get some flexible piping for it and try that.
 
_JT said:
Command thy woman to work :p But even if you use that extra effort, you will again run against the limitations of the tires right? That's the part I guess I'm not understanding :)
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Yes, you will, but you'll already have slowed down quicker than you were with the smaller disks/calipers :)
 
gsrek said:
wow lots of replies....but i think this has turned into an argument over oem vs aftermarket brake setup and the difference in braking power vs tire grip. my essential concern is brakes fading and my tires fading. i am going to be upgrading the brake setup pretty soon whenever i have the $$ saved up. but while the brakes are out i want to see if a can modify/fabricate a duct into the backside of the rotor while the knuckles are off to make it so much easier than putting one in while its still on the car.
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No, not at all, there's no arguments (well I'm not anyway :)) Just trying to put across the concept of how and why big brake kits work, as people do think because they can lock their brakes up, that's it.
I dont think I ever locked my FTO brakes up with the APs on, the car would just slow down, try and put your head through the windscreen, then stop. No lockups - which is exactly what you want, whether on track or just having a spirited drive on the road.
 
haitch said:
I now run the Brembo race calipers, stopping is night and day above any of the combos, zero fade, ultimate last second stopping.
Anybody who gets a pax lap in mine will feel the difference, the kit was pricey but discs and pads last for so long - outlasting all of the combos put together, this is where you save the money.
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Only someone who's fitted a big brake kit knows how much of a difference it actually makes over standard combos. I thought I had a good setup with the standard GPX calipers on my FTO with black diamond disks and EBC red stuff ceramic.
When I moved upto 4 pots I was easily keeping up with cars with 50bhp more on track because I could brake later and carry the speed through the bend. I miss that car lol
 
FreakyParts said:
Yes, you will, but you'll already have slowed down quicker than you were with the smaller disks/calipers :)
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But if you can't brake harder cause you lock the wheels, how can I slow down faster? I really don't get it :p
 
_JT said:
But if you can't brake harder cause you lock the wheels, how can I slow down faster? I really don't get it :p
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Ok... Its comparable to stopping two disks that have the same mass when one is say 10" in diameter and the other is say 36" in diameter (these measurements are exaggerated to demonstrate with less pinching force, but with the forces a brake caliper can exert a difference of just 30mm can make a huge improvement) if both the disks are spinning at the same speed and you tried to slow them as much as possible by pinching them between two fingers without completely stopping them, it would be a lot easier to slow the bigger disk and control its speed than the small one.
With braking, the most efficient braking action is with the wheel nearly locking but not quite this is much easier to achieve with a bigger disk than a small one, with the smaller disk the rise in force between pad contact and the wheel locking up is a very short steep line and bringing in the wheel to the point of almost locking up but not actually locking is difficult, with a bigger disk the rise in force between pad contact and the wheel locking up is a longer and less steep line so bringing the wheel to almost locking up without locking is much easier.
Although the bigger diameter disc has the benefit of greater leverage, the leverage increase is not what makes the brake perform better, if you can make the small disc lock up then it already has plenty of leverage, but it seriously lacks what they call brake modulation or control and goes from say 70% to lock in a very short distance of extra force applied.

Is that any clearer? :)
 
FreakyParts some great advice hear & it's great when someone takes the time out to explan things properly for others with not quite as much knowledge!:clap:

REP added for you sir!:nice:
 
FreakyParts said:
They're also 28mm thick and yes carbon-carbon disks which have far superior frictional, thermal and antiwarping properties, so nothing like normal, or even affordable upgraded road car disks :)
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Yes, but an EK9 is a unicycle with a popped tryre compared to an F1 car. :p

FreakyParts said:
Bigger brakes will improve the efficiency of the brakes, not just look pretty and give a better pedal feel. You'll be able to slow down quicker, later, more repeatedly and with a reduced chance of cooking your brakes.
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I'm not stupid enough to think bigger brakes and wheels wouldn't be better than a smaller one which is why I said 'upgrade' (stupidly ambiguous I know lol), I think there are quite a few people on the forum who use Spoon brakes and only a very small amount who use a bigger set-up than standard. If someone wants an EK9 brake upgrade Spoon is usually the first port-of-call, as they want to use the same pad and disks and size of wheels. It's at the Spoon 4-pots which everyone is raving about and go mad for that I was directing my comments.

After re-reading my previous posts, they read as if I'm trying to say a big Brembo set-up is equally as good as standard brakes, which obviously isn't true. When I was referring to Dixon Cheng I meant that there is very little difference between similar set-ups like the Wilwood to Brembo, or from stock calipers to Spoon calipers but NOT from Brembo to stock calipers (that would be silly :) ) Bigger wheels and a bigger brake set-up will obviously beat a smaller one.

I won't argue with the physics of it, but from my experience rallying an EK9 for a couple of years there is nothing wrong with the standard brakes, they are fit for use. We also run super soft semi-slicks on 15's so the tyres can't really get much better and though I keep saying about locking-up, my brother (the driver) has never complained about it grabbing. Perhaps the race-tracks put more pressure on the brakes, though I doubt it as the first few rallies we ran some rubbish pad and disk set-up we were recommended and the brakes ended up totally cooked and useless.

Good to have a bit of a discussion on it though, this is what makes forums so great and useful. I think the only way I'll believe that stock calipers can be beaten by something like the Spoon set-up is to see it myself. I'm sure bigger brakes with bigger wheels will out-perform the stock set-up, I'm just incredulous that any set-up using 15 inch wheels with the same size pad and disk but more pistons will do any better than standard calipers and warrant £650-1000.
 
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FreakyParts said:
Ok... Its comparable to stopping two disks that have the same mass when one is say 10" in diameter and the other is say 36" in diameter (these measurements are exaggerated to demonstrate with less pinching force, but with the forces a brake caliper can exert a difference of just 30mm can make a huge improvement) if both the disks are spinning at the same speed and you tried to slow them as much as possible by pinching them between two fingers without completely stopping them, it would be a lot easier to slow the bigger disk and control its speed than the small one.
With braking, the most efficient braking action is with the wheel nearly locking but not quite this is much easier to achieve with a bigger disk than a small one, with the smaller disk the rise in force between pad contact and the wheel locking up is a very short steep line and bringing in the wheel to the point of almost locking up but not actually locking is difficult, with a bigger disk the rise in force between pad contact and the wheel locking up is a longer and less steep line so bringing the wheel to almost locking up without locking is much easier.
Although the bigger diameter disc has the benefit of greater leverage, the leverage increase is not what makes the brake perform better, if you can make the small disc lock up then it already has plenty of leverage, but it seriously lacks what they call brake modulation or control and goes from say 70% to lock in a very short distance of extra force applied.

Is that any clearer? :)
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Yeah I get it and I think we were essentially saying the same. I have always understood the use of bigger disks, don't get me wrong (more mass to absorb heat and less fading, less force needed for slowing down at a given rate). I've always thought that more pistons/bigger piston surface do not increase the amount of force you can apply (given same disk, same wheels and same tires) but make it easier to control the brakes when trying to apply the maximum deceleration. Theoretically you won't slow down faster, but maybe in practice you will cause you can keep it at the edge of just not locking easier. That's what you're trying to say right?

Then there is the extra cost, which is imho not worth it when you take for example Spoon calipers - better get Wilwood or something with a bigger disk to have less fading and I think more control than when you only change the caliper.

Then again, the Spoon calipers might be good but they're overpriced cause it has the lable Spoon onto them :D A while ago I saw a thread. Spoon calipers are essentially rebranded Nissin calipers. Someone contacted Nissin and when there were 10 people or so for the calipers they could produce them once, for half of what the Spoon calipers cost.
 
Spoon calipers are made by Nissin for Spoon, they say nissin on them right next to where they say spoon........

In the same way that Spoon coilovers, the dampers are made by showa........

It's not that they are simply rebranding calipers, they have designed the calipers then had them made by Nissin, a very well established company specializing in braking products

Alot of people say they are overpriced tat, i would reserve judgement until you have actually used a set, they are fantastic calipers :)
 
Yes, I don't disagree on that, have never used them so can't comment on that. But when Nissin offers the exact same calipers, batch made starting at 10 sets for half the price...then I would call the Spoon calipers overpriced if they're exactly the same product :)
 
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