Good cheap disk setup

[GT6Steve]

I spent a Saturday morning in a brake supply shop studying a catalog that had all of these dimensions to choose the Isuzu discs.  We don't have the Capri discs over here but you do.  Why not use them as they're a proven fit?

 

Search out an online disc catalog for dimensions of all discs and pick the one that fit's your needs.

 

And share the link when you fiond it... ;D

[Urge]

Hi Steve

I have the capri disc set up on an other one of my Triumphs (GT6 mk1)

 

the reason for changing things is that on my spitfire, I am running 14inc wheels and it can handele a bigger disc and a bigger caliper.

[spitNL]

And share the link when you found it...

 

Here ya go:

http://www2.qha.com/catalogues/QH15.pdf

 

http://www.carparts-direct.co.uk/Performance_Brake_Discs.cfm

 

http://www.blackdiamondperformance.com/

 

http://www.brakesint.co.uk/

This one has the most info but finding a suitable disk will take long due to the search engine. click shop now, on the left.

 

and

http://www.brembo.com/ENG/catalogo_AM/2007/index.html

Has a 282MB catalog.

 

Cheers,

 

F.

 

 

Edit: use the Brembo site, it has the most info, and you can search by dimension.

[niko]

 

the reason for changing things is that on my spitfire, I am running 14inc wheels and it can handele a bigger disc and a bigger caliper.

 

You do not need this at all!

I run my racecar (1500 Spit, 144hp, 120+mph) with standard Spitfire calipers and EBC discs and dont have any braking issues, neither on std. GP circuits nor on the Nordschleife. You can get a decent set of Ferodo or Pagid pads for the type 14 calipers and braking is totally transformed (BTW: smaller disc diameter means better handling).

 

Not sure WHERE you want to run the Spit but I would second what Steve outlined above. He was lucky to be on a race track - how would you feel if your DIY brakes fail on a public road and you hit a bypassing car?

In Germany we often moan about TUV (UK: MOT) but when it comes to brakes I am more than happy that these guys are checking the cars...

 

my .02

niko

 

[Oracle]

In my Spitfire using the GT6 brakes and Mintex1144 couldnt handle two "quick" laps of the ring, the brakes totally gone on the 2nd lap, finished them all into Wiersiefen (spelling)....They were nearly ok, they were gone at the Adenau village bridge and Bergwerk but recovered by Klostertal, worked ok for the rest.

 

Probably have been fine using really good pads, I know the Mintex 1144 werent up to trackdays or marginal, cause within 2 trackdays and 1000road miles I had destroyed mine.

 

Mintex 1144 wear rate goes sky high when they start to smell. I fitted those pads the morning before I went to Nurburgring and used 1/3rd of a set in 12laps.

 

The Mintex 1144 isnt the best option for a trackday pad, its a good road pad. If you do trackdays you'd be better spending 2.5x as much money on Pagid's.

 

I was reading alot of stuff at the caterham site, some guys were getting 20-40 trackdays from 1 set of RS14 Pagids in the AP brake kit. Others getting 5-6 from Mintex. So on a long term scale the Pagid is better value if you intend to butcher your car. I read of some guys changing pagid pads cause they were really old  ;D

 

Never had a problem with my brakes on any other driving bar the Ring, spit or gt6 type. Agreed that if people stumped up the dollar £100+ for pads they'd not need to have big brakes, road and track all in one package.

 

Brings me back to my point about selling braking kits with useless pads, the caterham AP brakes using the supplied AP basic pads aren't actually any better than the stock ones using 1144 in terms of feel, they are not giving the feedback of my GT6 ones, worse as the pads give no feel.

 

They take longer to warm up so they are going to be "snappy" and wooden alot of the time as they don't retain heat. That's also why you need a "quality" pad cause they produce MUCH more initial cold bite than pads of a compound for heavier and often servo'ed cars as per Mintex G-Tech material.

 

Surely want to impress the customer, in a market with no opposition there is no need to sell a budgetised pad and let down your entire product.

 

What the Caterham brakes are good at though is giving a bone hard pedal, not even the slightest runout, no awareness of the brakes actually working bar the force involved, ie no shudder, feedback, vibration. Quality disc material being AP and well made. Also they should reliably stop my car from high speed Also even on the cheapo supplied pads I can do multiple high-speed stops with no aroma from the brakes.

 

Agreed that in most cases a brake upgrade isnt needed, just a pad upgrade.

 

I always used to use factory pads (1960's ones) in my standard brakes, it was only when I moved to EBC green I had fade and overheating, EBC pads are not an upgrade.

 

The Canley discs look identical to the AP ones. They are quite unique as the unmachined areas are black, most discs are machined all over I assume as they cost £170 each at the Caterham cause they are a bit better than some £40 ones, even with an aggressive markup.

 

Canley kit looks to have the market sown up, just avoid the cheap pads. What are the other options? There are no other options that dont use spacer blocks and I think wilwood stuff is not very good. You cant go wrong with AP.

 

I assume the calipers are AP also? Spec sheet just gives stats.

 

This is why I don't want wilwood or hi-spec stuff, you want to reliable brakes!

 

Unless you drive HARD you probably don't need a brake upgrade If your brakes have NO bite, feel and are wooden they will work if you just change pads. I know I've used "county" and EBC pads.

[niko]

I used to use EBC Yellow on the racer. In combination with the grooved discs they were performing fine. EBC Green are not suitable for the Nordschleife IMHO.

Now I am starting to try Ferodo DS3000+03 due to the very high c/f. Need to balance the rear, hence my thread on Porterfield.

Have no experience with Mintex but as hardly anyone in DE is using them this may tell a bit. Pagid and Ferodo lead the pack here.

 

cheers

niko

 

PS: spelling is almost correct: "Wehrseifen". This is where my MX5 brakes started to smell and fade....now having Tarox G88 slotted discs and EBC Green (only available road legal pad for that brake) installed and things are completely different :-)

[Urge]

Hi all

First off I am building a toy, have been for to long now, marriage and buying a house etc etc we have all been there.

 

This toy is not only ejoyed at the driving stage, but at the building stage also.

 

So to over do some thing aint alwyays the wrong thing to do.

 

I dont feel that I am over doing anything, I have a spit mk2 with a fiat twin can, once finnished, it will be around 160 to 180 bhp.

 

I have over done the rear end (subaru LSD, stright shafts) in case I ever feel the need to turbo my lump, a lot of these fiat twin cams turbo very well with big power gains.

 

So the need for good brakes is to do the job once, I CAN ALWAYS USE THEM LIGHTLY  

 

I wont pay any thing like £90 for pads,

 

buy the time you have bought a few sets of these you will be into a lot of money.

 

I think it far better to build a set up, that might need to have bigger brakes but use chaper pads.

 

chaper brakes with expensive pads will soon over take in money, my way of doing things, and also, I have the option of putting expensive pads in bigger brakes and them have a far supirer set up.

 

how could you beeter the expensive pads on a small brake set up ?????

[DaveNotSoSideways]

Green Stuff have quite a lot of initial bite from cold but I found they grab a bit, for me after the 2nd heavy loading they were past their best. They start to smell quickly, I'd never use them again.

 

Again for me the Mintex 1144 has slightly less cold friction than the EBC but its vastly superior for much more heaving loadings and needs just light use to bring them into their best (which isnt that much better than cold), they stay good for a much longer period than the Green pads and retain a solid, if unspectacular, level of feel.

 

You can better the pads on the standard brake by using better materials

 

The pad used in a spitfire is used on the standard caterham brakes, lotus elan, there are loads of compounds. The GT6 calipers the pad is the same as many other cars, check the thread in the tech section related to interchangeable parts. You can buy about 15 types of pad. All of them cost around £60-180. You get what you pay for

 

[mattius]

i hated the greenstuff on my car, they had a nice bite but then nothing, switched to the 1144's and its a much better all round feel to the brakes.

[willcolumbine]

I didn't actually mind the Greenstuffs to start with. I think that was because at the time I was using the car everyday and the roads round here largely consist of straight bit, roundabout, straight bit etc etc so basically I was braking from cold every time and for that Greenstuff actually aren't too shabby. On the kind of roads where you're on the brakes all the time and putting a lot of heat into them they do fall down. Don't get me wrong though - they are still better than the standard pads supplied nowadays!

[Urge]

Hi

Any one got the spec of an original solid GT5 disc, or a link

 

Many thanks

[RK]

I wont pay any thing like £90 for pads,

 

You're a fake, arent't you?

 

You get what you pay for.

 

For small money you can get pressed camel muck as type 14 or type 16 brake pads. I'm shure they sell the same pressed camel muck for a little more as larger pads for 6pot brembo or AP calipers.

 

You converted your rear end to subaru diff, converted the engine to a 180hp twin cam and now whining about some 90UKP for a set of decent pads?

 

Makes me giggle, somehow.

 

Reinald

[JohnD]

My setup:

Princess four pots - probably unnecessary.

Capri vented discs - an enormous improvement, as I always cooked the brake sbefore

Mintex 1155 pads  Ditto.

And that's on an 850Kg Vitesse, plus  95kg me, so more to stop!

Even on the 'Ring, no significant fade.

 

Of course, Niko, you may say I wasn't going fast enough, but I was happy with a ten minute lap.

 

urge,

the advantage of a bigger disc is not a bigger caliper with a larger pad.

It's that the same sized pad has a greater 'lever', or moment, to apply retardation.

Just like moving a tight nut  - a long lever will shift it when a spanner can't.

Have a look at fancy six pot calipers - they are small and grouped on the rim of the disc, to obtain the greatest leverage.

 

There is NO advantage in a larger pad.

Friction depends entirely on the pressure between the surfaces.

Bigger pad with same force from brake system means less pressure per unit area, but as you have more area, that friction force is multiplied by a bigger number. Result - retardation remains the SAME as it was before!

 

John

[Urge]

I understand all to well about the mercanical advantage of long spanner over a short one, and I agree with you 100% on that,

That is why motor bikes(some) have massive discs but not massive calipers and pads.

 

But you cant tell me small pads are better than larger ones, if that was the case, why dont we put even smaller calipers on our cars, why botter going from spitfire calipers to GT6???

 

why asume I wont increase the peddel force to inprove the pressure appiled to the lager pads???

 

To all the sceptics out there, I spent loads of time looking at the brembo catilog, took loads of measurments and came up with these puppys.

 

http://cgi.ebay.co.uk/ws/eBayISAPI.dll?ViewItem&item=370264417220&ssPageName=STRK:MEWAX:IT

 

Arrived today, took em down to my unit, an guess what, bloody brilliant.

 

takes the disc about 3mm away from the steering track rod end  ;D

 

they fit with in a 14inc alloy wheel that I have got (6x14 five spoke revolutions with triumph PCD)

 

with the disc set in the alloy, it leaves 1 and quarter inc to the out side of the inside of the alloy, the standard GT6 caliper sticks out 1 inc from the disc  ;D

 

the inner hole for the hub is a much better fit  ;D

 

the  disc are  a bit heavyer i grant you, but I will save that on some alloy calipers whe I work out there sizes

[Urge]

when I get five mins, I will take some photos

 

but just to relate the pads sizes to lets say wider wheels.

 

narrow tyers will give a much higher force on the road surfice than a wider tyer, but they wont give you better grip!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

 

why, its to do with the surface area that is with in contact with the road.

 

small pads, more prussure, bigger pads less prussue, more contact erea

 

big pads, with more pressure bingo

 

added to that the mercanical adantage of a caliper thats further away from the center of the disc/

[James]

Urge - what size tyres are you putting on this beast?

[GT6 Nick]

So to summarise, you'll redrill Peugot 283mm to suit GT6 hubs and make new caliper mounts? The picture on eBay suggests it's a shallow disc (assuming it's not just a generic photo), so are you putting the disc on the rear of the hubs like the originals?

 

I fitted this Rally Design kit to Cortina front suspension - http://www.rallydesign.co.uk/product_info.php?cPath=562_563_567&products_id=3935&osCsid=5nmkn6kthokisae378bjgg82f3 - 285mm discs and Wilwood calipers, and they just fitted inside 14" rims. Sadly, they don't offer a big disc for GT6s.

 

Please post some photos!

[SimonPearse]

narrow tyers will give a much higher force on the road surfice than a wider tyer, but they wont give you better grip!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!/

 

What do you mean when you say that narrow tyres give a higer force on the road? I don't understand what you are saying.

If the vehicle is stationary then the force on the road depends on the weight of the vehicle. Ignoring the fact that wide tyres generaly weigh more than narrow tyres, the force would be the same and, assuming the same tyre pressure, that force would be applied over the same area. (contact patch area is dictated by weight on the wheel and tyre pressure, the width of the tyre has nothing to do with it.

[AJ.Lintern]

I think he's referring to the force per unit area being higher on a narrower tyre.

[SimonPearse]

why would the force per unit area be different? THe contact area would be the same and its only the contact area that is exerting the force.

[Urge]

Hi yes sorry guys

My dyslexcia means I dont explain to well

 

the cars weight does not change. but it is spread across the contact erea of your tyre, so the wider the tyre the more contact erea.

 

lets say your contact erea is one square foot per tyre,

now if we double that to two square feet, as the cars weight CANT change, there is less force per given squarefoot of tyre

 

so a wider tyre has less force applyed to it from the cars weight at any given size

BUT wider tyres because of there wider contact with the road, give better grip.

 

now aplly that to small brake pads,

small brake pads, lots of force per given contact erea but less contact erea and less grip

 

go one step further and imaging a brake pad the size of a pencile tip.

 

how would that work, pants right, bet there is loads of force on its contact face

 

back to what I am doing.

 

I will be more that happy to take photos and keep you up to date on how well this mod goes.

 

it is looking good I must say,

just need to find a decent caliper,

Wont buy new, or one off specials

 

might look at the Brembo fiat coupe caliper or the like.

these have dust seals and are cheap enough second hand.

 

but I must do some more measuring first

[esxefi]

all i know is;-

 

i would rather have a bird standing on my nuts wearing doctor martins than a pair of 6" stillettos

 

does that put it in perspective? ;D

[SimonPearse]

OK, now I understand what you are saying, but you are making  a common mistake.

Wider tyres DO NOT give a bigger contact area.

lets say the weight of the vehicle is 2000 lb and that it has even weight distribution.

It follows that the weight on each wheel is 500lb.

 

Lets say that the tyre pressure is 25lb per square inch.

The contact area may be calculated to be 500/25 = 20 square inches.

The width of the tyre does not enter into the equation.

 

A wider tyre gives a different shape of contact patch and would allow a softer compound to be used without compromising tyre life.

 

I know that this is counter-intuitive, but if you do a web search you will find confirmation from bridgestone (cant remember where, it was a few years ago).

I once tested the theory (using newspaper, shoe polish and bathroom scales with a selection of tyre sizes on my kit car.

[AJ.Lintern]

So you're saying if I put bicycle wheels on my car it would have the same contact area as if I put F1 slicks...? ??)

[SimonPearse]

I don't think you have quite got it yet.

If you were to fit bicycle wheels and then slowly lower the car onto the ground the contact area would grow (as the weight came on) as the patch increased the sidewall of the tyre would compress until the rim bore down on the tread: you would exceede the load carrying capacity of the tyre. At this time the wheel would no longer be acting as a pnuematic tyre within it's operating range. However (assuming you did not burst the tyre) if you increased the tyre pressure to say 250psi (and still taking the weight on the tyre to be 500lb) then the contact patch would be 2 sq in.

If you then fitted the car with f1 tyres and inflated them to 250 psi then the contact patch would be 2 sq in.

If you then fitted the car with 165/70*13 tyres and inflated them to 250 psi then the contact patch would be 2 sq in.