Brake Vs Wheel size

[kenan]

I need new wheels and brakes for my car but can't decide what to go for and wanted advice from people who have been there as it were.

I would like 15s as it keeps the unsprung wheel weight down but want big brakes so I can stop. 310 brakes with 16s seem a good compromise but are they overkill?

My car will be a weekend car and I will take it on track say about 4 times a year. Would the Willwood 280mm set-up be upto the job? as these would fit nicely under a set of 15s and that means cheap tyres :roll:

 

[marcymarc]

You thinking of my wheels bud :lol:

 

[kenan]

You thinking of my wheels bud :lol:

Am tempted, just not sure if the 280 Willwood kit would last on the track ect... That srtut brace came up real well with some polish

 

[scottgtirxxx]

I am keen to see peoples thoughts as i have 15's and am considering a brake upgrade.

 

[pulsarboby]

it all depends on how hard your gonna be pushing your car on the track, if thats what your going to do! if you just want to mosey round the track then they will be fine, but if your gonna do some real hardcore driving, then forget the 280's.

the 280 discs simply are not big enough to disperse the heat generated on a hard run trackday!
also depends on the circuit you are driving on, if there are a lot of bends such as brands, lydden etc then they definately wont be upto the job.

so this means 300mm discs minimum for your average trackday, which will mean 16'' rims in a majority of cases.
but if your a hardcore trackdayer or racing then there not up to the job either.

i went for the 8 pot kit although i really never wanted to run 17'' rims but there has to be a compromise for great stopping ability, afterall thats where a lot of races are won or lost

last on the brakes, makes good haste;-)

and that saying is very true.

so i would say in a nutshell for the average joe......run 310mm discs with 4 pots and 16'' rims

 

[MarkTurbo]

Would the Willwood 280mm set-up be upto the job? as these would fit nicely under a set of 15s and that means cheap tyres :roll:

With the right wheels 310mm wilwoods will fit under 15's ;-)

 

[Braveheart]

Very acurate answer from Bob....

I'm using Wilwood 285mm 4 pots kit under 15" rims but not all 15" will fit over that kit.
I have 2 sets of 15" wheels. Buddy Club 6.5x15" with Toyo R888's 205's and Team Dynamics Pro 1.2 7x15 with Toyo T1's 195's the Buddy club are ET42 and do not clear my wilwood 4 pots without 10mm spacers but the Team Dynamics are ET35 and clear the 4 pots without spacers.

With regards to there performance, the first track day with the new kit showed a vast improvement over the OE stoppers but when braking hard after a long staight into a second gear hairpin, I felt that I could benifit from a bigger break kit... :doh:
I was using smart pads (track use) and they were finished after 5 track sessions.
I changed to PolyMatrix Q's for the next track day and they worked better.
Think it was a combination of new drilled and grooved disks and high metal content pads.
Now that all the rough is off the disks, the pads are lasting and my peddle is not dropping away as I brake hard and car slows well.

I like the handling characteristics of my car and am reluctant to fit larger wheels.
Power will have a big part to play as well.... I'm only running at 16PSI (1 bar) maybe 280-290BHP but if and when I up the power I may be struggling with the 4 pots and have to break earlier that I'd like resulting in slower lap times...:sad: .

Interested to see how Bob gets on with big power, 17" wheels and 8 pot braking...
Think I could catch him on the twisties.... :lol: :lol: :lol: ;-)

 

[Braveheart]

Also, get a brake master cylinder support bracket off Steve as this has improved the feel and performance of my brakes.....

http://www.gtiroc.com/forums/showthread.php?t=48685&highlight=master+brake+cylinder+support

 

[kenan]

Also, get a brake master cylinder support bracket off Steve as this has improved the feel and performance of my brakes.....

Yeah got one of them, among other things from Steve



So sounds like the 280s are a no go then, bugger there goest the budget :doh:

Thing is I find it hard to pay out for a 310 set-up when I can get the same as Bob for not much more money and 17s cost feck all more that 16s these days. I just feel the 330 will be overkill with my driving style (would look great).

Bob how did you get on with teh HiSpec set-up you had and long do you recon before you'll have you car rolling for a report of the brakes in use?

 

[kenan]

With the right wheels 310mm wilwoods will fit under 15's ;-)

Which ones matey Speeline/compomotive I assume

 

[pulsarboby]

the hispecs were fine for normal or fast road driving, but tbh i found that if i really pushed the car hard around the twisties, then i could cook the brakes 'and thats not on the track' where they will be under much harsher use.
so i then decided to go with the 8 pots, im sure these will cope with anything i can throw at them, but then i have the dis-advantage of moving upto 17's!
but tbh most cars in euro saloons or barc are running 8 pots, so i need to be able to compete with the big boys on the stoppers so i had little choice really.

im hoping to have my car up n running by xmas, then i can let you know what there like, but i wont really put them through there paces untill the cars on circuit, thats where the real teller will be. but that wont be till end of january time.

as i said in the brake thread though, think the 8 pots are overkill for a road going car. but at the end of the day it depends on your finances, perhaps your mrs or girlfriend will by you a set for xmas lol

 

[kenan]

perhaps your mrs or girlfriend will by you a set for xmas lol

If she finds out how much any of the brake kits I'm dead.

I think the 310s should sufice then, I'm not somone who is hard on the brakes just wanna know I can stop when I need to. Now I gotta find some wheels . . . . . .

 

[pulsarboby]

yeah i think the 310mm are the best all round bet tbh
do what most people do (everything cost £50 lol) cant go wrong that way:lol:

 

[fubar andy]

So sounds like the 280s are a no go then, bugger there goest the budget :doh:

I’ve always said make the best with what you’ve got and I try to do that to the best of my ability.

With regards to disc sizes and the amount of calliper pistons that you can have I’d just like to share my views about what I’ve done and tested.

At the moment (some people will already know) I use the 280mm Wilwood 4 POT kit. The original kit from Rally Design is crap really, the discs are poor and the pads they offer are shocking to say the least.

However, there are some different paths that I’ve chosen to increase the efficiency and overall performance. Without going on and on I’ll get to the point:

If you want uprated disc’s the fitment for a Renault Laguna’s after market discs are spot on to use, there 280mm and 24mm thick, granted not F1 brakes, but it’s a start. Choices of groves and heat treated etc etc, you can pick ‘n’ mix what you think you need.

Next, pads: When I brake, it’s hard and as late as possible – pretty normal for racing/trackdays, but the main problem I have is heat, lots of it. Previously I’ve used Mintex 1144 ( 44’s) and there fine for road, but on track, your wasting your time. 55’s? There ok, but there’s lots of squeal and for me even they are going off after a while. So now I’m on 66’s. “They don’t make them for Midilites” I hear you cry, they don’t but they do for Dynalites and with a bit of modification they now fit my Midilites! And last but no means least the rears now house 44’s

Brake fluid has also been replaced with AP Racing’s AP600 and braded lines are installed all round.

The other thing that I have fitted (although it was only a quick test and I will install these better at a later date) was air rams from the bumper to the discs. The original ones are shite and do fúck all anyway, so some old K&N 57i cold air feed piping was used to direct air on to the discs.

With all this in place and pads bedded in, I’ve been out testing. The stopping power from this setup is phenomenal, the brakes are strong, the fade is non-existent and the the coefficient is good. The disc’s have not warped or cracked (which is a big thing for me) and my peddle no longer travels to the floor!

Now, this is only a short period of time, although I’ve hammered the crap out of them my big test is somewhere like Oulton Park where I can test them much more rigorously over a period of 10 laps+.

The feedback I’ve got from people about the 310mm kit from Wilwood is that they warp far too easy being a pathetic 21mm think and in a nut shell cannot take a hard bashing when it comes to a trackday.

I’m still ongoing with my quest for a “Wilwood Mutilation Kit” with thicker 310mm (or bigger discs), better cast bells and heat treated to a greater heat tolerance, but I’ll post more when I get it!
Overall it’s a case of how you drive, how often you’re going to be using them this way and your budget. If you want to keep 15’s and you feel that your not going to benefit from bigger brakes then sit down and think seriously about what you want. Don’t be bought from “sales-washing” (brainwashing) and find people that have been in similar situations and are also kept to a budget, sometimes simple things can save £££’s but be just as effective if not more that spending vast amounts!

I’m still on going with pad choices and disc’s so this isn’t set in stone but its vast improvement and I’ve learnt so much from this that I feel its been worthwhile ;-)

 

[kenan]

I can tell you what I want and thats the same as my current 205 set-up. I put the Peugeot 206 GTI 180 brakes on her which run 283 disks with standard pads etc. On the road they are great and on track the stop me very well, but like I say I'm not one for braking late or that hard really. More happy throwing the car into the bends and enjoying myself but not really racing anyone.

Thing is the GTI-R weight that much more so I would of thought I'd need bigger braks to cope with the extra weight/heat created.

But if you happy with your current set-up the way you sound like you drive then it could do for me.... I just really don't know and nobody near me has these set-ups for me to go for a ride with :doh:

 

[fubar andy]

I'm not one for braking late or that hard really. More happy throwing the car into the bends and enjoying myself but not really racing anyone.
Thing is the GTI-R weight that much more so I would of thought I'd need bigger braks to cope with the extra weight/heat created.

If you’re not going to hammer the brakes that much, I had (my personnel choice) a set-up of Wilwood 4 pot’s, groves disc's, mintex 55’s front and 44's rear, braded lines all round and decent brake fluid. – worked fine and shouldn’t have any major problems. Just make sure there's plenty of cooling to the discs

 

[kenan]

would this be with the 280mm setup and you can get the 1155s as a direct fitment for them. Where would you normally get your parts from?

Cooling is another project to keep me busy then

 

[fubar andy]

would this be with the 280mm setup and you can get the 1155s as a direct fitment for them. Where would you normally get your parts from?

Cooling is another project to keep me busy then

Yes this is with the 280mm kit. Mintex do 55's for midilites, but not 66's. Any competent parts supplier should be able to supply you with those pads.
My parts come from a local motorsport shop, but if you have something like that near you they are the people to see. Demon Tweeks are also stockists of Mintex pads

 

[kenan]

I think I just had an idea . . . I could order the 280 kit and use and abuse it. If I found I wanted the bigger kit surely I could just get a different adapter for the calliper to space it out more and then the bigger disks (with bells). This should work and if I waited till the disks were dead than the price difference would not be to much?