Big Brakes

[Rich-xstS3]

Ive noticed on here that when people speak about big brake conversions its pretty much a choice between the Brembo GT or the Porsche conversion. I spoke to Jim at Star Performance and he mentioned both a Tarox 6 pot 330mm conversion and a Stop Tech 4 pot conversion. Anyone any experience with these? Just fancy something a bit different to the red Brembo's. Also found that Hi Spec Motorsport do a 4 pot conversion aswell. Again anyone using this?

Cheers folks

 

[voorhees]

what are you planning? trackday,qtr mile,show?

 

[Rich-xstS3]

Well hopefully big turbo by the end of the year. Just want to take the necessary precautions before I do. Pat my shants a few times on back road blasts as it is never mind what itl be like with 300+ bhp

 

[Ess_Three]

I've known people with the Tarox 6 pots have issues with sticking pistons as their dirt shields aren't as good as they could be.

Stop Tech are very good...but more expensive than Brembo, which they are based on...so why spend more?

High Spec stuff I've also heard of dirt shield issues...and warping sidcs...but many run them with no problems.

If it were my money again, I'd opt for a big name that is proven on ROAD cars (with all weather use, proper dirt shields, corrosion resistance etc) and opt for Brembo. They make the Porsche stuff anyway...so why pay more for a calliper that says Porsche and not Brembo...unless you have more money than sense.

The Brembo GT kit works so well...there just isn't a need for more, in my view...and you can buy spares from your local SEAT dealer.

 

[Rich-xstS3]

Im not really bothered about the Porsche brakes. I dont want to lose brake pedal feel because as you say they arent matched to the size of the master cylinder. Do the issues with cracking discs normally only happen with track day abuse? I know its only the drilled dics that do this but as I understand it the GT kit comes with drilled discs but if I bought them from a Seat dealer it would just be normal vented discs? If I can get a set of calipers from the scrappy is all i need is caliper mounts and discs? pads too obviously.

 

[S3Steve]

If you want a top quality kit but dont want to go for the brembo's, why not look at the AP Racing Formula brake kits, there stuff is excellent quality and are used by loads of race and rally teams around the world.

http://www.apracing.com/car/site.htm

 

[steve123a]

Had some Hi Specs on a previous car and did have a few probs with the discs warping, but the actual calipers were good quality!

 

[Ess_Three]

If you want a top quality kit but dont want to go for the brembo's, why not look at the AP Racing Formula brake kits, there stuff is excellent quality and are used by loads of race and rally teams around the world.

http://www.apracing.com/car/site.htm

Make sure you look at the ROAD brakes from AP...not the RACE stuff.
The race callipes haven't go full dirt shielding to allow you to run them through salty roads in winter etc...I looked into AP stuff previously and AP advised me to stick to the road stuff only.

Race stuff is meant to be re-built each season...not what you want on a road car.

This is a prime example of where people go thinking it's for a race car...so it must be good. No...different use completely. Stick to road kits from the big makers and you should be OK.

 

[Ess_Three]

Im not really bothered about the Porsche brakes. I dont want to lose brake pedal feel because as you say they arent matched to the size of the master cylinder. Do the issues with cracking discs normally only happen with track day abuse? I know its only the drilled dics that do this but as I understand it the GT kit comes with drilled discs but if I bought them from a Seat dealer it would just be normal vented discs? If I can get a set of calipers from the scrappy is all i need is caliper mounts and discs? pads too obviously.

The Brembo GT kit is all you'll ever need on the road, and I'll argue that as long as I've got a hole in my ****!

Even for trackdays, change the pads to something more suitable (Feerodo DS2500s or similar) and you'll have all the brakes you'll ever need.

The LCR kit is fine...if you worry about cracking the cross drilled discs, go for standard LCR discs and run aggressive pads.
Remove the dirt shields from behind the disc too, to let more air in to cool them (a good tip on standard brakes too)

I believe Brembo can supply the GT kit with grooved discs, although I've only seen one S3 with them (lucky sod!)

 

[S3Steve]

Make sure you look at the ROAD brakes from AP...not the RACE stuff.
The race callipes haven't go full dirt shielding to allow you to run them through salty roads in winter etc...I looked into AP stuff previously and AP advised me to stick to the road stuff only.

Race stuff is meant to be re-built each season...not what you want on a road car.

This is a prime example of where people go thinking it's for a race car...so it must be good. No...different use completely. Stick to road kits from the big makers and you should be OK.

Actually mate i'm fully aware of this, I actually used to work for one of the biggest AP Racing dealers. This is why i recomended the Formula kits which are designed for road cars ( not race cars) and come with dust seals. The formula kits are manufactured in the same production facility using the same methods as there competition stuff hence the excellent quality.

 

[Ess_Three]

Actually mate i'm fully aware of this, I actually used to work for one of the biggest AP Racing dealers. This is why i recomended the Formula kits which are designed for road cars ( not race cars) and come with dust seals. The formula kits are manufactured in the same production facility using the same methods as there competition stuff hence the excellent quality.

Accepted...I wasn't aiming the comment at you personally...

Sadly, too many people are taken in by the whole 'Race' must mean better than 'Road' thing...which is total crap.

From memory, the Formula AP stuff has better quality coatings and shields, which makes then more suitable and the better finished. Win-win surely.

But some muppets will still want 'race car' brakes on their car...and they'll suffer for it.

 

[S3Steve]

Fair enough mate, just wanted to clarify that the formula kits are in fact designed for road use and hence a definate alternative to the Brembo GT kit.

As for the "race car" must be better than "road" point, I agree with you and have came across it in the past with road car customers who wanted the same kit we were using on race cars because they thought it would be best. Thankfully most our customers listened to our advice and bought what we recomended in the end.

 

[Rich-xstS3]

Yeah it was the road spec stuff I looked at. Just have to phone up one of the dealers and get a price. Im not really concerned too much about the drilled discs cracking. Itl maybe get a run round Knockhill once or twice if i ever get time. I just remember reading a previous thread about the drilled discs cracking.

 

[S3Steve]

Yes mate drilled discs are more prone to cracking i would stick with grooved discs mate.

 

[glen_jai]

Is there really a need for bigger brakes on an S3?

I find the standard brakes pretty good.
Although am planning for a big turbo conversion next year, so am tempted to fit some bigger calipers on the front.

Anyone out there running big turbo power on standard brakes? If so, how do they fair?

Cheers

 

[Stewart]

Is there really a need for bigger brakes on an S3?

I find the standard brakes pretty good.

Cheers

You must drive like a pussy then! The standard brakes are dire when pushing on.

Anyone out there running big turbo power on standard brakes? If so, how do they fair?

Cheers

Sorry, they cannot reply as they are deceased after not being able to stop in time!

 

[glen_jai]

You must drive like a pussy then! The standard brakes are dire when pushing on.

haha... cheeky bu99er. You're probably right though

So I take it big brakes are a must with big turbo power.

Cheers Stew.

 

[Aky]

Crash bang wallop

 

[Stewart]

Crash bang wallop

From your sig you must save your 'spirited' driving for 2 wheels but I bet the R6 wouldn't be half as much fun with crap brakes eh?

Just try a section of road that you know with 2 or 3 roundabouts in succession and boot it between them, I.e as fast as you can. By the third donut you will certainly be having brown trouser moments. They will fade to nothing.

The Brembo GT kit which is almost identical to the Seat Leon CupraR setup is the one that everyone will recommend. 323mm disks with Brembo 4 pot calipers and some decent fluid and you'll have complete confidence in your car's stopping ability.

I run 334mm disks with Porsche GT3/C4s calipers and the stopping power is immense with no fade, ever. No loss of pedal feel for me at all, in fact better feel over standard and R32 brakes.

 

[glen_jai]

From your sig you must save your 'spirited' driving for 2 wheels but I bet the R6 wouldn't be half as much fun with crap brakes eh?

You're quite right mate. The bike is used for letting off stress, while my car is used for comfort commuting.

The Brembo GT kit which is almost identical to the Seat Leon CupraR setup is the one that everyone will recommend. 323mm disks with Brembo 4 pot calipers and some decent fluid and you'll have complete confidence in your car's stopping ability.

Excellent. The Brembo's sound good, and are a good price too. I'll opt for those I think. Are standard rear brakes ok? And do the Brembo's fit behind standard 17s?

Cheers.

 

[Stewart]

Yes and Yes

 

[Backdraft Motorsport]

Most of our Big Turbo conversion customers either have or go for bigger brakes. With the heavy weight of the S3 the standard brakes fade quite quickly under heavy braking. Add more power and speed and bigger brakes will be needed. We always recomend an upgraded rear disc and to make sure the same brake pad compounds are used front and rear.
Regards
Mark
Backdraft Motorsport.

 

[s3ollie]

I run 334mm disks with Porsche GT3/C4s calipers and the stopping power is immense with no fade, ever. No loss of pedal feel for me at all, in fact better feel over standard and R32 brakes.

Second that. I have the GT3 calipers also and they are far better than standard setup, no loss of pedal feel at all and much sharper with more bite.

People make out your pedals going to almost hit the floor if you use brakes with bigger pistons. but not so with the GT3's id say less or the same pedal movement as before

 

[Ess_Three]

Second that. I have the GT3 calipers also and they are far better than standard setup, no loss of pedal feel at all and much sharper with more bite.

People make out your pedals going to almost hit the floor if you use brakes with bigger pistons. but not so with the GT3's id say less or the same pedal movement as before

Strange...not like the S3s I've driven with Porsche callipers...and to be honest, even with the LCR type Brembos.

The pedal travel is always longer...it has to be...it's simple maths.

Try driving the car they came from to see how the brakes should feel! (Porsche...not LCR, as the LCR has the same MS as the S3)

 

[Ess_Three]

Most of our Big Turbo conversion customers either have or go for bigger brakes. With the heavy weight of the S3 the standard brakes fade quite quickly under heavy braking. Add more power and speed and bigger brakes will be needed. We always recomend an upgraded rear disc and to make sure the same brake pad compounds are used front and rear.
Regards
Mark
Backdraft Motorsport.

I don't agree...
I've driven S3s with uprated rear discs and it seems to me that all you do is give the rear suspension more work to do with the additional weight, and the ABS more work to do.

I've never found the need...on a front engined car the fronts do 90% of the braking anyway...so why uprate the rears?
It makes the rear potentially more twitchy...there is no weight there to make the brakes work.

Also, I wouldn't run the same pad compound front and rear either...harder at the front where you can make them work and get the heat into them that the uprated compounds need...softer/standard at the rear to make sure they work at all (from cold, with no pre-warming) or don't get too grabby.

Different ideas for different driving styles I guess...

But in 15 years of trackdays and competition in front engined, FWD (or predominantly so) cars I've never run the same compound pads front and rear (except standard pads...or mild upgrades like Greenstuff...all the 'proper pads have been split compounds)

 

[s3ollie]

I know the maths say the pedal will move further and it obviously will but it really isn't noticeable. maybe its having new fluid and pads.

How much more travel does the maths say the pedal will move with the GT3's? bet its practically nothing

 

[Ess_Three]

Well it was 15-20mm more on my LCR set up, over standard, and they have smaller volumes than the GT3 set up...

Maybe you don't notice it...but it has to move more.
Do you not feel that the pedal has lost feel?

Outright stopping is there, if you push the pedal...but little feel at the top of the braking stroke, when the brake pedal is up by the throttle?

 

[Backdraft Motorsport]

I don't agree...
I've driven S3s with uprated rear discs and it seems to me that all you do is give the rear suspension more work to do with the additional weight, and the ABS more work to do.

I've never found the need...on a front engined car the fronts do 90% of the braking anyway...so why uprate the rears?
It makes the rear potentially more twitchy...there is no weight there to make the brakes work.

Also, I wouldn't run the same pad compound front and rear either...harder at the front where you can make them work and get the heat into them that the uprated compounds need...softer/standard at the rear to make sure they work at all (from cold, with no pre-warming) or don't get too grabby.

Different ideas for different driving styles I guess...

But in 15 years of trackdays and competition in front engined, FWD (or predominantly so) cars I've never run the same compound pads front and rear (except standard pads...or mild upgrades like Greenstuff...all the 'proper pads have been split compounds)

Braking is a very personal thing. As a race car builder and driver I have to remember that this forum is predominantly advising people on setups for the street.
However, on a road car safety is paramount. Its not just about driving hard on a race track with warmed up brakes. Its about pulling out of your road on a cold morning and a child walking out in front of you.
The reason we advise for people to use the same compound front and rear is that it is important for them to work at the same rate. This will stop one end grabbing and locking whilst the other end is still warming up.
Also, there is no reason why an uprated disc and pad combination will weigh any more than standard. It is just important to remember that the S3 does carry a significant amount of weight to the rear with the Quattro system so 90% front brakes is a bit excessive. I would agree that uprating the rear caliper is a waste of time. we even run standard rear calipers on our Audi TT and A4 race cars.
I hope I haven't seemed to come onto your forum and contradict you, I just want to explain where we get our opinions from and that it is just that an opinion.
Regards
Mark
Backdraft Motorsport.

 

[Ess_Three]

Braking is a very personal thing. As a race car builder and driver I have to remember that this forum is predominantly advising people on setups for the street.
However, on a road car safety is paramount. Its not just about driving hard on a race track with warmed up brakes. Its about pulling out of your road on a cold morning and a child walking out in front of you.

Very true...

The reason we advise for people to use the same compound front and rear is that it is important for them to work at the same rate. This will stop one end grabbing and locking whilst the other end is still warming up.

OK...
But in my experience, the froints do 90% of the work...so if that's the case, you will never warm up the rears at the same rate, so by fitting 'colder' or 'softer' pads to the rear, you do ensure even brake torque throughout the operating range.

My experience of proper competition pads is that they need a good shove to get the initial bite, and that shove gives the heat...once warmed they work more progressively.
On a Front engined FWD, (I'd class the S3 in here too) you will never get enough heat into the rears to get progressive braking.
Certainly, that's my experience.

Also, there is no reason why an uprated disc and pad combination will weigh any more than standard.

Doesn't have to...but most likely does. Bigger, heavier disk = more gyroscope effect, and harder to get turned in.
No?

It is just important to remember that the S3 does carry a significant amount of weight to the rear with the Quattro system so 90% front brakes is a bit excessive.

I agree, if we are talking static weight distribution.
But distribution under heavy braking, an S3 has to go 85% over the front, anyway...I'd have thought?

I would agree that uprating the rear caliper is a waste of time. we even run standard rear calipers on our Audi TT and A4 race cars.

I'm not surprised...they don't do much and I can't see the need for more rear brakes.

I hope I haven't seemed to come onto your forum and contradict you, I just want to explain where we get our opinions from and that it is just that an opinion.
Regards
Mark
Backdraft Motorsport.

Hell no, Mark.
Always good to hear other opinions.

I am guilty of trail braking...so I prefer my cars set up with aggressive front brakes and little rear, to prevent the rears grabbing and spitting the back out.

I run S3 312mm stuff on the front of my Mk3 GTI with Mintex Racing F4R compound pads (very aggressive, very high initial coefficient of friction, cold or hot) and EBC Redstuff on the rear to make sure the rears don't grab too much.
They work for me, with my driving style.

 

[Backdraft Motorsport]

Yep Fair play.
I like your attitude to opinions and I like this particular forum more.
Maybe you should put your money where your mouth is or some other well known saying I cant remember and climb aboard one of our race cars for some real fun?
Still confused as to why discs with holes and grooves weigh more but apart from that there seems to be a method in your madness!
It's Friday night, why are we on a forum? Is it to do with tyhe fact that the baby is in bed, the missus is out and my car has to stay on the drive?
Nuff said.
Regards,
The human also known as Mark.
Backdraft Motorsport.

 

[Ess_Three]

Yep Fair play.
I like your attitude to opinions and I like this particular forum more.

:thumbsup:

Maybe you should put your money where your mouth is or some other well known saying I cant remember and climb aboard one of our race cars for some real fun?

Maybe I will...

Still confused as to why discs with holes and grooves weigh more but apart from that there seems to be a method in your madness!

I don't recall saying they would.
But uprated discs, as in larger diameter and thicker, will almost certainly weight more.

I guess if you get pedantic, grooved discs should weigh a few grammes less...
As should cheapo drilled discs.
But discs cast with strengthening round the holes will possibly weight more.

I'm also unsure of the whole argument that 2pc discs weigh significantly less...
A single piece disc with a slim cast mounting face vs a single piece rotor of the same size but with meaty cast mounting lugs, a beefy alloy hat (has to be to get the strength of iron or steel and say 12 high-tensile nuts and bolts...

Just because some big brake kits have alloy hats...doesn't make them significantly lighter. The alloy isn't primarily there for light weight (besides, it's weight saving at the wrong part of the 'disc')...
But there you go...they look better, so must be better, eh?

It's Friday night, why are we on a forum? Is it to do with tyhe fact that the baby is in bed, the missus is out and my car has to stay on the drive?
Nuff said.

Or that I'm stuck 150 miles offshore on an Oil Platform, on nightshift!

 

[jojo]

I see where this rear disk weight saving is heading, Mark(of Backdraft) is thinking uprated disks and pads of the same size, and Glen(Ess) is talking about uprated kits Like ECS stage 1 rears with 2 piece 308mm rotor and hats setup.