FAO anyone running 4-pot calipers.

[Patrick_g46]

I am going to be fitting my 406 brembos soon but im worried there might be a problem with them working properly. Someone has said to me i might need to change the matser cylinder? :? Something to do with the fact there will be too much pedal travel as well? I cant see how that would be but i thought id better check and see if anyone has had any problems!

Thanks
Patrick

[richy]

you need to see what size the pistons are and work out the TPA (total piston area) for the 4pots and compare against the std calipers TPA, ideally you need the TPA to be slightly higher, that way it matchs your master cylinder and shouldnt be any issues with longer/shorter pedal travel and more/less clamping power.

[The King]

4 pots are massive overkill on a clio, and tend to cause more problems than they solve. Yes the slave cylinder will likely be larger than the one in the standard caliper and so pedal travel will increase.

At the end of the day if your brakes can lock the tyre and brake its contact with the road then you dont need them. The only exception is if you want to save unsprung weight. I cant see brake fade being an issue because clio cup cars dont run 4 pots.

4 pots are generallyneeded on heavy cars because the extra weight produces more heat and need a more efficient system.

The calipers on F1 cars are tiny. Larger does not mean better.

[MAXIBOY]

why keep comparing everything to a F1 car this has no relevance..unless you know of a carbon disc and caliper combination for a clio..thats the same price as a set of peugoet 406 calipers and 172 discs

if you do i would like one..

[16v_paddy]

Get them on!

As richy said, just find out the TPA & go from there, you'll more than likely end up with a bit more travel in the pedal but have increased clamping force :wink:

[The King]

why keep comparing everything to a F1 car this has no relevance....

And why do you always call your car a maxi car when it clearly is not?

You know its not a maxi. We know its not a maxi. You know that we know that its not a maxi.

[The King]

Get them on!

As richy said, just find out the TPA & go from there, you'll more than likely end up with a bit more travel in the pedal but have increased clamping force :wink:

Why would you need increased clamping force, when the original caliper has enough clamping force to break the tyres traction with the tarmac?

[J o n]

'almost' agree with Rob, 4 pots are indeed complete overkill and with decent pads will start doing endo's! Having said that the standard Williams calipers have always been crap imo, I had nothing but trouble with them and that was buying new.

[MAXIBOY]

why keep comparing everything to a F1 car this has no relevance....

And why do you always call your car a maxi car when it clearly is not?

You know its not a maxi. We know its not a maxi. You know that we know that its not a maxi.

and this has what to do with a braking thread.. :lol:

as for my car why does it bother you so.. :shock:

[J o n]

stay on topic Rob.

[richy]

Get them on!

As richy said, just find out the TPA & go from there, you'll more than likely end up with a bit more travel in the pedal but have increased clamping force :wink:

Why would you need increased clamping force, when the original caliper has enough clamping force to break the tyres traction with the tarmac?

hes not saying you need more clamping force, but when choosing 4pots for a car you need to find out the TPA for both the standard caliper and 4pot caliper and try get it as close as pos, if not with slightly higher clamping force rather then less.

[The King]

Get them on!

As richy said, just find out the TPA & go from there, you'll more than likely end up with a bit more travel in the pedal but have increased clamping force :wink:

Why would you need increased clamping force, when the original caliper has enough clamping force to break the tyres traction with the tarmac?

hes not saying you need more clamping force, but when choosing 4pots for a car you need to find out the TPA for both the standard caliper and 4pot caliper and try get it as close as pos, if not with slightly higher clamping force rather then less.

And he winked, 'infering' the increased clamping force would be some sort of benefit. Which it wont.

[richy]

its certainly a benifit over choosing the wrong calipers and reducing pedal travel but decreasing the clamping force to less then standard!

[16v_paddy]

Do some research :wink:

http://www.williamsclio.co.uk/forum/viewtopic.php?t=30962

All I know & care about is that with 4 pots my clio stops a hell of a lot quicker, in much shorter distances (and yes I did get busy with the tape measures) with not even a sniff of fade while driving it properly

I couldn't give a monkeys greasy jock strap if my "inference" of clamping force being increased because of the 4 pots is right or wrong, hell for all I care it could be down to voodoo or the aurora borealis but my wilwoods rock & I wouldn't go back to standard calipers

[LEIGH-ANNE]

:clap:

[The King]

Do some research :wink:

http://www.williamsclio.co.uk/forum/viewtopic.php?t=30962

All I know & care about is that with 4 pots my clio stops a hell of a lot quicker, in much shorter distances (and yes I did get busy with the tape measures) with not even a sniff of fade while driving it properly

I couldn't give a monkeys greasy jock strap if my "inference" of clamping force being increased because of the 4 pots is right or wrong, hell for all I care it could be down to voodoo or the aurora borealis but my wilwoods rock & I wouldn't go back to standard calipers

It cant stop quicker with 4 pots. The limiting factor in you stopping is the grip the tyre has with the road. Ones the caliper is able to break this traction (ie lock a wheel) there is nothing you can do to the caliper to make your car stop faster.

To stop a clio faster you would need to:

Increase rear bias so they do more work.

Fit grippier tyres so the point of breaking traction with the road is delayed.

Arguing against these points is arguing against the laws of physics.

[LEIGH-ANNE]

http://i304.photobucket.com/albums/nn181/leighanne24/cars/Aretha-Franklin-Here-We-Go-Again-11.jpg

[16v_paddy]

Well the only things that changed when I put the calipers on was the calipers themselves, slightly longer braided brake hoses & different compound pads. Same tyres, same discs, same fluid no other changes at all.

and guess what?.....the car stopped a hell of a lot quicker and in much shorter distance. The same thing also happened when I replaced all the old & worn braking components for brand new everything....you do the calculations if you like as I can't be bothered as all I know & care about is that my car is better for having 4 pots....end of 8)

I'm not arguing the laws of physics, maybe just arguing against someone elses interpretations of the laws of physics :roll: in fact I'm not even arguing, merely pointing out my own findings from deciding if 4 pots were a worthwhile investment for my little clio

[The King]

Well the only things that changed when I put the calipers on was the calipers themselves, slightly longer braided brake hoses & different compound pads. Same tyres, same discs, same fluid no other changes at all.

and guess what?.....the car stopped a hell of a lot quicker and in much shorter distance. The same thing also happened when I replaced all the old & worn braking components for brand new everything....you do the calculations if you like as I can't be bothered as all I know & care about is that my car is better for having 4 pots....end of 8)

I'm not arguing the laws of physics, maybe just arguing against someone elses interpretations of the laws of physics :roll: in fact I'm not even arguing, merely pointing out my own findings from deciding if 4 pots were a worthwhile investment for my little clio

When its wet what happens to your braking distance?

[16v_paddy]

Well the only things that changed when I put the calipers on was the calipers themselves, slightly longer braided brake hoses & different compound pads. Same tyres, same discs, same fluid no other changes at all.

and guess what?.....the car stopped a hell of a lot quicker and in much shorter distance. The same thing also happened when I replaced all the old & worn braking components for brand new everything....you do the calculations if you like as I can't be bothered as all I know & care about is that my car is better for having 4 pots....end of 8)

I'm not arguing the laws of physics, maybe just arguing against someone elses interpretations of the laws of physics :roll: in fact I'm not even arguing, merely pointing out my own findings from deciding if 4 pots were a worthwhile investment for my little clio

When its wet what happens to your braking distance?

If you have to ask maybe you shouldn't be allowed to drive on the public roads :P

[The King]

You wont answer the question because you have realised that by answering it, you will prove yourself wrong.

In the wet braking distance increases.

Why?

Because the grip the tyre has with the road is diminished and this grip is the PRIMARY determining factor in braking distance.


If this is true in the wet, give me one reason why this law of physics doesnt apply in the dry?

Your caliper theory is wrong. When you accept that the money you spent on 4 pots was wasted, you can get on with making your car faster.

[16v_paddy]

When did I say it was a theory? Did you actually read what I wrote :?:

Every muppet knows what happens to braking distances in the wet :roll: what has braking in the wet have to do with what I measured while trying out my various stages of new brakes in the dry?

[Laine_16v]

I agree with Rob.

[16v_paddy]

Maybe me & my car are freaks of nature :lol:, somethings broken or the bias had been played with by the previous owner with a knackered old brake setup who knows :?:

Can anyone shed some light on why my 4 pots out perfomed the previous setup in the dry :?:

and before we start bleating on about wet braking, I didn't test or measure anything in the wet, I'm just more sensible & leave extra room, time & space to compensate for other peoples ****ups on the road. So not really in any position to comment either way

[Tommo]

If you refurbed your calipers, fresh fluid, new pads and discs with your previous set up then I think you would have noticed a huge difference tbh. The 4 pots probably feel better as everything is new

[The King]

and before we start bleating on about wet braking, I didn't test or measure anything in the wet,

You have completely missed the point. Wet weather was mentioned because it illustrates the following well:

The main factor in your car stopping in how much grip you have from the tyres

If you want to stop more quickly fit tyres that grip the road better.

[robi1000]

I think that 4 pots aren't of any help at low speeds, where as Rob says only limiting factor is tyre grip. But with decent tyres (r888) I would definitely want to have them when I drive on twisty road at speeds around 150km/h (95mph) for about 20km and then road becomes a even more twisty and downhill (check Petrol-Ferrari hillclimb race). My granny lives at the starting line and when I go to pick her up, there's some serious abuse on the brakes. And trust me, I rarely get brake fade because I tend not to brake unless I really need to, but on that road standard calipers just aren't good enough. On the vid you can see at around 1:25 when they drive downhill why you need good brakes (there's a Williams at 1:44 and 3:10 and 3:28 where he almost crashes).

http://www.youtube.com/watch?v=gTrr-ySfToU

I think that's where 4 pots might help. While we are at it there's probably no way I could fit 406 Brembo 4 pots under stock williams speedlines? What about speedlines 2012?

[The King]

That is motorsport. Brake upgrades can be useful here. Mainly to prevent boiling brake fluid. 4 potstend to disipate heat better.

Most of the people on here use their wilwoods to get to maccy d's.

[16v_paddy]

If you refurbed your calipers, fresh fluid, new pads and discs with your previous set up then I think you would have noticed a huge difference tbh. The 4 pots probably feel better as everything is new

I done that 1st. New calipers all round, goodridge lines, discs & pads etc then a while later went with the 4 pots. So I got big improvement with the new bits, then got more improvement with the 4 pots fitted


You have completely missed the point. Wet weather was mentioned because it illustrates the following well:

The main factor in your car stopping in how much grip you have from the tyres

If you want to stop more quickly fit tyres that grip the road better.

Ok I'll give you that, as I missed the point :roll: but how do you explain the improvements I found in stopping distances in the dry with my car after I went from brand new standard stuff to 4 pots, while still on the same tyres?

Did I get lucky with the TPA being spot on for my cars setup? Was there something mechanically wrong with the standard setup to start with?

Theory now seems to suggest 4 pots wouldn't make an improvement, but experience (with my car at least) says otherwise. How? Why?

[robi1000]

That is motorsport.

Well I don't drive on two wheels, but I have to say that even when I am not racing and I'm driving for myself I'm not much slower (about 85% racing pace). I admit that there's a lot of people just showing off (kind of) and not really driving it hard, but then again there are people like me that drive the car like Renault intended. :twisted:

[The King]

If you refurbed your calipers, fresh fluid, new pads and discs with your previous set up then I think you would have noticed a huge difference tbh. The 4 pots probably feel better as everything is new

I done that 1st. New calipers all round, goodridge lines, discs & pads etc then a while later went with the 4 pots. So I got big improvement with the new bits, then got more improvement with the 4 pots fitted


You have completely missed the point. Wet weather was mentioned because it illustrates the following well:

The main factor in your car stopping in how much grip you have from the tyres

If you want to stop more quickly fit tyres that grip the road better.

but how do you explain the improvements I found in stopping distances in the dry with my car after I went from brand new standard stuff to 4 pots,

Could have been air in the lines before. Cold have been glazed pads on before. Could have had a blocked line. Any number of things.

[16v_paddy]

I can believe that's a possibility with the old & worn crap. But then everything was replaced with all new stuff, definately fitted & bled properly and got a massive improvement. Then the 4 pots were fitted about 8 months later & more improvement :?

[MAXIBOY]

If you refurbed your calipers, fresh fluid, new pads and discs with your previous set up then I think you would have noticed a huge difference tbh. The 4 pots probably feel better as everything is new

I done that 1st. New calipers all round, goodridge lines, discs & pads etc then a while later went with the 4 pots. So I got big improvement with the new bits, then got more improvement with the 4 pots fitted


You have completely missed the point. Wet weather was mentioned because it illustrates the following well:

The main factor in your car stopping in how much grip you have from the tyres

If you want to stop more quickly fit tyres that grip the road better.

but how do you explain the improvements I found in stopping distances in the dry with my car after I went from brand new standard stuff to 4 pots,

Could have been air in the lines before. Cold have been glazed pads on before. Could have had a blocked line. Any number of things.

there speaks the voice of denial what calipers are you running.

[Patrick_g46]

Right ok when i get around to fitting mine I am going to Make a note of lots of different brake tests on the standard set-up and then i will swap over to 4 pots and see the differences. The results will be posted up and you guys can bitch amongst each other untill your hearts content! :lol:

[16v_paddy]

Whack the ****ers on, 4 pots rock 8) end of :delete:

[Patrick_g46]

Whack the f**k**s on, 4 pots rock 8) end of :delete:

Even if they dont improve stopping distance they still look ****ing epic when driving about 8)

[Patrick_g46]

especially when you have repainted them in bright red and restickered them 8)

[Paul16v]

i run renaut 21 tx discs wih standard calipers with carrier brackets to move the calipers out.

They are more then enough, in fact feel too good on ocassions lol.