I need facts on what performs and works please.....

Hi all,

I`ve trawled the forums (including others) and still cannot find definite facts re brake upgrades (primarily) for track use.

I am aware of the varying options regarding brake upgrades and am about to go down the route of installing a 9" servo, 22.2 mm master cylinder and rear proportioning valve (I have rear discs) however I need to fit bigger front brakes but need to know…

Who has tracked successfully and can offer hard facts regarding the 256mm brake route via vauxhall calipers as against the 284/288mm types. Are the bigger brakes needed in what is at present a 1.8 8v (but to be upgraded over the next winter) Are the bigger brakes overkill ie: do the 256mm with decent pads and a high boiling point fluid work on track?

I want to go 2.0 16v and am toying with 1.8T so understand bigger/better brakes are required however………

What wheels fit over the bigger 288mm brakes. There`s plenty of discussions about getting the right wheels but no facts on specifically who has done what and I dont want to experiment if its been done successfly before. What type and offset work?

Similarly I note that in order to fit the bigger calipers a thinner pad has to be used so as to fit under some wheels thereby negating or reducing the availability of fitting decent pads in the correct size for the caliper for track use. Hence the issue above with wheels that allow full use of aftermarket/performance pads available for the VX calipers.

Finally, what pads are used from experience with success with these set ups on track. I use Performance Friction on my Porsche 951 but these too may be overkill on a lightweight Golf (and expensive) but they work well on cold road discs and dont disappear on track when combined with ATE fluid.

Sorry for all the questions but if all are answered from people who 1) have done it and 2) from people who have experienced success with it then it will be a useful FAQ and will compile a lot of info info under one heading  8)

As example

288mm calipers -
Car type
Hose type
Pad (road)
Pad (track)
Wheel make
Wheel offset
Fluid type

284mm calipers -
Car type
Hose type
Pad (road)
Pad (track)
Wheel make
Wheel offset
Fluid type

256mm calipers -
Car type
Hose type
Pad (road)
Pad (track)
Wheel make
Wheel offset
Fluid type

Can't offer experience with 256/280mm brakes, but I have used 239mm standard discs and Ferodo DS2500 pads, on track (Oulton Park). I was also running sticky tyres (Yokohama Advan 032R).  I also did Oulton Park previously, with road tyres (which will mean less braking effort required to lock the wheels), stock discs and pads and the car performed okay on the day but subsequently, the pads were glazed and needed replacing. On both of these occasions the car has 9" servo and 22mm master cylinder, and is a 2.0l 16V motor. For info, I am not planning any larger brakes, although when it comes time to disc replacement (which is a while away) I might go to a higher spec disc of the stock size, 239mm. (This is so I can run 13" alloys). Hope it helps.

PS DOT 4 brake fluid and standard rubber hoses (braided hoses don't make any difference).

Hi Paul

Thanks for the feedback. Thats very interesting and sort of confirms what I thought about bigger brakes in relation to the cars weight. My 800kg ish Westfield and Ginetta G27 both had around 200bhp and were ok with 250mm (ish) solid discs and Green Stuff pads (however I wouldnt recommend the current green stuff pads)

I`m inclined to think that 256mm vented discs should be ok with good pads and a higher spec brake fluid.

I agree with you regarding braided hoses, they are a luxury and less prone to damage and bursts but do improve the feel of the brakes when not running a servo.

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Any other track day warriors got any feedback? Especially with high power engines?

I assume you mean 280mm set up as fitted to g60 mk2 golfs and mk3 gti's up to 96…as the 288mm set up from later mk3s is a different thing all together. (also the 280mm calipers are the same as mk2 16v calipers from 88 on just with a different carrier)

braded hose will help improve pedal feel as they do not expand under hard braking like rubber ones will. ~(rubber hoses are fine to start with but get them hot and give them some abuse and they will soon start to go a little soft, which will gtet worse with age as the rubber degrades.

28mm calipers - Lucas / girling 54 calipers with adaptor brackets
Car type - mk1 1.8gti stripped
Hose type - braded front and rear (middles to rear beam still rubber)
Pad (road) - mintex front and dephi cheap nastys on the rear
Pad (track) - EBC custom ones (as yet un used)
Wheel make ASA
Wheel offset 33
Fluid type - halfords dot 5.1


I have the above set up, but I am yet to give it a full on abuse on track, last time I was on in Oct I was still running drums at the rear and the stock 20mm MC, this was ok but gave a long pedal. also the halfords road pads got too hot and glaized so were like glass!!

since then I have fitted a 22.2mc 9" servo, and rear discs with mk4 calipers. I have also change the discs for groved ones to help keep the pad face cleana nd reduce gas build up under heavy braking.

I am yet to drive the system in anger but the inital signs are good. the pedal feel is a bit better (I will be using a vac bleeder at work soon to try and improve this further..) and poss a new MC as well (the one on there is a older one which has been used to just test the system and prove it works…) the main issues I have is the rears are too good at the mo and even with cheap pads its too efficent, but I have some more limiters to go inline to help this, but the results so far are good.

for track use I have some nice pads coming from EBC that have been built for track use, I am unsure as to the compound at the mo as I havent got them in my hand yet but when I do get them I will report back.


also note that depending on the wheel design you may need skinner pads when using mk3 calipers, BUT all you need are the pads listed for mk2 16v cars that are from 88 onwords. these pads are ~15mm thick, where as mk3s are ~19mm thick most proper pads will come in both sizes but double check, I am yet to find a problem.

other things to take accountt of are the disc and hows its finished, ie grooved or plain etc,  pad material, ie organic, smi metalic ( we aprove alot of the reg90 pads at work, (anything with an e11 number will be us) and cheap does not always mean bad…nor does a odd name.

also note that how the pads have been bedded in will change things, the wheel style (turbos look good but dont provide much cooling..heavy wheels dont help), the fluid (im doing alot of looking into this as just going by the dot number wont always help), and the tyres too, as the brakes can only be as good as the friction betwen the tyre and the road…

Great input, thanks.

Hi M7R

Great input, thanks. If we get more its a useful database hopefully all based upon experience, what works and what fits.

I assume you mean 280mm set up as fitted to g60 mk2 golfs and mk3 gti's up to 96…as the 288mm set up from later mk3s is a different thing all together. (also the 280mm calipers are the same as mk2 16v calipers from 88 on just with a different carrier)

I meant the Vauxhall caliper options, many sizes available and cheap and bolt straight on.

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Re pads glazing (and some brake fade)………..

This is considered to be due to the resinuous compound that forms the pad and `holds` the abrasive particles heating up due to extreme heat and turning to gas thereby forming a layer between pad and disc that colls off and the pad is smoothed as the surface has been semi molten.

There are 4 ways to avoid this 1) better bigger brakes 2) drilled discs and 3) grooved discs 4) higher temp pads

Bigger discs offer better mechanical advantage and with a bigger pad area they absorb and lose heat more effectively.

Discs with the holes actually cast in them (Porsche OEM for example) are less prone to cracking as the metal grain is unbroken and flows around the holes. Discs with holes drilled in them are prone to cracks as the holes `cut the grain.

Grooved discs have grooves in them (obviously) but the principle of both is to break up this gaseous layer. The grooves on some discs also act as a wear indicator.

Higher temperature pads will help but the added heat can then transfer to the caliper piston via the brake pad and boil the fluid in a small disc/caliper set up.

Sounds like you should go with higher temp pads as you have the larger brakes but I`ve heard poor things about Yellow Stuff and Red Stuff pads - anyone used them successfully?

I recommend ATE blue brake fluid.

I agree about wheel weights as unsprung weight is a disadvantage and reduces turn in to some degree.

Hilux said

Sounds like you should go with higher temp pads as you have the larger brakes but I`ve heard poor things about Yellow Stuff and Red Stuff pads - anyone used them successfully?

I recommend ATE blue brake fluid.

I agree about wheel weights as unsprung weight is a disadvantage and reduces turn in to some degree.

drilled discs are fine, but pad choice will be criticle to top the holes filling up and then being useless. which is why I go for groove discs,these clean the face and allow a route for gasses to escape wth no real down sides apart from they can be a little noisy depending on the design of groves.

on the pads I will be able to tell you in a week or so what material I have, but its not a off the shelf material, the pads I will have are R&D ones.

Im not sure what brake fluid im going to try yet, it depends what i can get hold of easily but wont rob me blind!

this is a really informative guide that i came accross on the web, not sure if its got the info that your after but its worth a read.

http://www.matey-matey.com/brake_conversion.shtml

can any body tell me the part numbers on the uprated master cylinder and servo so i can have a look down my local srapyard
or what i need to look out for cos there are a couple of audi's and vw's down there.

thanks

Thanks Joe, a very useful site.