Big brakes!! What are you running?

[deviant]

Bump..

A bit of an update to this thread. I hate when tech threads get left with no resolution!!

I ordered the Wilwood 1 inch master cylinder kit from 949racing a good few months back and finally managed to get it fitted last week.

Well what a difference!! Pedal is hard and takes a nice firm pressure to use. I start to get braking happening right at the top of the pedal and then I can press harder and only get a couple of inches of pedal movement with progressively harder braking effect....sounds silly but the more I press the pedal the harder it brakes. I can modulate the pressure much more accurately now. Before the MC was fitted the pedal would sink at least half way to the floor with no feel at all and the brakes would snatch and lock all to easily.

Something else was sorted with this MC to. With the stock one fitted I would apply the brakes 3 or 4 times and each time the pedal would get harder but then if the brakes were not used for a short period the pedal would go soft again.

I will reserve my opinion of 949Racing for PM's.



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[little decks]

6 spot APs!!!!

with 330mm AP discs

custom hats and dog bones

... total weight = less than Mazda factory brakes

[Okibi]

Love those APs, will they fit inside the factory 15s?

[little decks]

No,

I doubt you could even get a 16 over them, the wheels pictured there are 17s and you can see it is still a bit tight

[deviant]

Those AP's look lovely!

My wheels ar 16's and fit very nicely over the brakes.

As little decks mentioned these aftermarket brakes are LIGHT! I took one of my front calipers off to take some measurements for getting new pads made and they are so so light. Absolutely no weight in them at all.

I have not had a disc off yet so I will be interested to weigh one when I need to. There has got to be a lot of 'flywheel effect' from huge. steel discs?!

[manga_blue]

I'd say that replacing the rear lines with stainless ones would take out a fair bit of mushiness too. The rubber gives a lot more than you'd think.

[greenMachine]

to take some measurements for getting new pads made ...

Have you tried some of the local competition brake suppliers for pads - if they haven't got them, they can probably get them. I used a local Canberra supplier to get me some trick Mintex pads for the GM when I was tracking it, and they ordered it in for me from UK.

Most of the weight savings in BBKs is in going to be in alloy hats and the calipers (if alloy) - the disks themselves do not vary that much on a size-for-size basis AFAIK.

But if you are looking to save unsprung weight - and who isn't? - going to bigger disks can reduce the potential gain, or even eliminate it, and bring other complications.

On the racecar I have a Willwood setup on the front, and relocated stock caliper on the rear with a Willwood disk, all on custom hats, and I use 15s so the disk is not too heavy, the wheels are lighter and the rubber cheaper. The limiting factor is grip at the contact patch, the advantage of the bigger disks is they are less prone to fade because they can hold more heat, and perhaps feel/modulation.

One benefit of the Willwoods is the range and ready availability of pads.

[deviant]

I'd say that replacing the rear lines with stainless ones would take out a fair bit of mushiness too. The rubber gives a lot more than you'd think.

It's on the to do list. I have read a test report that suggested that rubber lines in good condition should not really give much but I'm thinking that any give at all is not going to help and if there is any give in the rear lines having a mahoosive MC is going to make that problem worse.

to take some measurements for getting new pads made ...

Have you tried some of the local competition brake suppliers for pads - if they haven't got them, they can probably get them. I used a local Canberra supplier to get me some trick Mintex pads for the GM when I was tracking it, and they ordered it in for me from UK.

Most of the weight savings in BBKs is in going to be in alloy hats and the calipers (if alloy) - the disks themselves do not vary that much on a size-for-size basis AFAIK.

But if you are looking to save unsprung weight - and who isn't? - going to bigger disks can reduce the potential gain, or even eliminate it, and bring other complications.

On the racecar I have a Willwood setup on the front, and relocated stock caliper on the rear with a Willwood disk, all on custom hats, and I use 15s so the disk is not too heavy, the wheels are lighter and the rubber cheaper. The limiting factor is grip at the contact patch, the advantage of the bigger disks is they are less prone to fade because they can hold more heat, and perhaps feel/modulation.

One benefit of the Willwoods is the range and ready availability of pads.

If i remember rightly the disc and hat can be seperated on this kit. I'm not sure if the hat is ally or not...it's certainly not the nice, smooth finished and anodised thing you would get from some manufacturers.

Pad supply has been easier than expected to set up. As with most aftermarket caliper manufacturers they have gone with a common pad shape.
I have always used GSL Rallysport and the A1RM track pads they offer. They were able to tell me that EBC list Tarox patterns in their range so it was just a case of measuring a pad and finding the pattern that matches. From that part number they were then able to find a number of options.
Believe it or not but the pad shape matches that of ones used in Mercedes commercial vehicles so there is currently a set of pads in there designed for a 3500KG van. I have not used these super hard but they work perfectly on the road and to be honest in a car as light as this with such huge discs I can see that they would work on track quite well. These pads were a mere $100!! I have got a set of A1RM track pads being made up to for $180ish. I used these compound pads in my lard arse WRX and they lasted way beyond their designed temperature range so should work extrememly well in an MX5.

Grip is going to be a concern now however I think that with practise I am going to be able to fully use what is there, the pedal feel is that good now and the brakes so reactive that I should be able to modulate them around the locking point. I need practise and seat time! It's no good trying to use them hard on the road...honestly these brakes could stop a train and it would need silly amounts of speed and commitment to really get stuck in to them on the road so it will have to wait until I am on track.

[little decks]

If you buy good quality discs like APs they are actually incredibly light. The AP discs we are running are alot lighter than a DBA 5000 series which are a smaller disc

[deviant]

Cheers Davex3!

Little decks...Have you priced up replacing the discs on their own? Scary or not bad?

With my pad choice I am not envisioning huge amounts of disc wear but it is still nice to know if I should be starting some long term investments and taking a second job

[little decks]

Well my Dad actually custom made that kit, machined the hats and caliper brackets himself and bought all the componentry seperate, and the discs cost about $700 each

But the AP disc should last quite a while, particularly on such a light car.

[rascal]

....., and the discs cost about $700 each

[greenMachine]

^ What he said, x2

Can't remember what the Willwood disks were, but IIRC they were a fraction of that. I know you can get DBA disks too, but I don't know their pricing.

Longevity can be boosted by proper heat treatment prior to first use, I did mine in the oven in the kitchen, I have heard of people using electric frypans too .

[rascal]

Longevity can be boosted by proper heat treatment prior to first use, I did mine in the oven in the kitchen, I have heard of people using electric frypans too .

GM,
Can you shed some more details on this?
I am picking up new disks later this month for my NB8A, (they were $45ea ) and anything which helps their longevity and may help keep my ongoing costs down sounds good to me...

[greenMachine]

I can't remember the details, but it involved heating the disks over a period of a couple of hours, and then letting them cool slowly. IIRC there were a couple of stages, heating to a level, leaving it for a while, then going up to the next step, and so on. I remember it tied up the oven for best part of an evening and overnight.

Try the Willwood site, or even google.

I don't know how much of a difference it makes, but it was pretty simple and mainly only cost time, so little at risk. Certainly, I have no reason to think that it harmed disk life, but there are sure to nay-sayers out there somewhere.

My 2c.



PS Yes, even at $45/disk, money still doesn't grow on trees.