AP Racing brake kit

[david_f]

Hi Chaps. Just to let you all know that I am working with AP Racing to develop a bolt-on kit for the NSX. The kit will comprise 330mm front discs with six pot callipers and 330mm rear discs with four pot callipers. AP Racing recommend groves discs for Track Day work. The only downside is that you will need 17" wheels front and rear. The kit should be available in early January. I'll keep you posted! Regards, David.

[ctrlaltdelboy]

I suggest you liaise with Kevin on this as he has already done considerable work in this area and continues to do so.

it makes sense for you to get together and consolidate your efforts rather than work on essentially the same project independently in parallel.

[mcibuk]

You are no doubt already aware but Dirk in Germany? (see NSX Prime) has developed brake assembly using 330 mm discs and standard calipers (minor mod) for 17" wheels.

All this development sounds great for you guys that want to race cars on the track but can anyone recommend a system that will upgrade brake performance for standard road use without reverting to larger front wheel?
If the discs looked prettier (grooved or drilled) that would be a bonus.

Appreciate that the develpoments suit folks that want to use or test their NSX's to the limits but for me i'm content with power/handling but would like the satisfaction of having a brake set that will stop me just that bit quicker!

[ctrlaltdelboy]

I am aware of Dirk's work also and you are right, all of this work is really for track cars.

with regard to brake upgrades for road cars there's not really a great need for this IMO, however you can get a decent upgrade by changing the front disks to Black Diamond grooved (around £150) and trying different brake compounds in the std calipers (see several posts on this in this forum) whilst also removing the dust shields from behind the disks and adding some deflectors to direct airflow onto the disks.

these mods should be more than adequate for upgrading the brakes for a car that will only see road use

[Kevin]

Regarding the work I have done / still doing. After starting this project, with Hispec brakes, in Feb, I nearly have a fitted system. However I'm not sure what I want to do now. This is the history;

Kit measured and ordered in Feb
Kit finally delivered in June. Was supposed to be 6 weeks, after hassle and lies from Hispec.
Kit did not fit. Front brakes too big (they made them bigger than I orginally specced). Rears, just wrong.
Sent kit back, was supposed to be two weeks for rework.
Went to Hispec and got my bits back in Sept. My parts had just been sitting on the bosses' desk, doing nothing.
Bought new wheels which are now 17" in front.
Looked at what the problem with the fronts are, and got local engineers to make new mounting bells for the front discs.
New bells took 2 days to make! Are better quality than Hispec too.
Kit is just about to be finally fitted.
Now need to sort out rear kit.

It is because Hispec are so totally useless, crap and a bunch of liars, that I do not know what to do about making a kit to sell. I have also not wanted to say anything about them until I got my kit to fit.

It is not going to be easy to make a kit with a new caliper that will fit under the 16" wheel.

The problem is making a bracket to mount a new caliper, and not increasing the rotor size by a significant amount. With the 16" wheel I think the largest rotor is going to be 315mm. Going from 280 to 315mm is not enough, it causes problems with the bracket. My front kit is 325mm, and even then making the bracket was difficult and some special things had to be done. It's to hard to explain why exactly without seeing it.

The question is therefore, should I continue to develop a kit that will fit the 16" wheel? I now have the brakes I want on my car.

The other dilemma is that the caliper I have used from Hispec is a special slimline design, that allows it to fit under the wheel, without a spacer. I haven't seen another caliper which is this slim.

I know what needs to be done to design a kit that will fit the 16" wheels. I have most of the drawings already in my AutoCad system. I need to find a manufacturer of a caliper that makes a slim model.

Don't forget, TAROX already make a kit that fits the 16" wheel. These can be bought from any TAROX dealer.

If there is demand for a kit I could do one, over winter.

Oh, and I haven't even tried the kit out yet, it may even turn out not to be worth the effort!

[david_f]

Hi Guys, my thoughts are these. Standard road NSXs don't really need bigger discs/callipers they are better than most already. A big improvement (and reasonably priced) is to simply fit Ferodo's DS2500 front pads; better bite and feel, no squeal (I wouldn’t bother changing the rear pads for strictly road use); call Tim Phillips at Circuit Supplies on 01525 385888. If street guys want cross drilled (to look nice - although they will be weaker remember), go to Dali Racing or Science of Speed or others for off the shelf discs to fit the 16" front, 17" rear configuration. For those of us that want exciting track day cars, I would suggest we need 330mm discs front and rear with, I suggest, 6 pot callipers at the front and 4 pot rear. Because of this, 17” wheels all round are a necessity. Some work needs to be done to accommodate the rear handbrake mechanism with this configuration but AP Racing (http://www.apracing.com) is up for the job. Accordingly, I suggest that those of us who want the track day solution wait for AP Racing to make the kit. I don't know what the cost will be at the moment but one thing's for sure; it will work and work well! AP Racing's reputation will be on the line and it will have been fully tested on track (by me!). I'm hoping to have it on the car in the next 6-8 weeks. As I said, I'll keep you all posted. Regards, David.

[mcibuk]

All comments re standard road car upgrades most appreciated - Thx

Good luck with sorting out a good solution for track day use - still very interesting from teh sidelines.

[Kevin]

The main aim of my kit was for it to fit the standard wheels, unfortunately it didn't work out. 325 vs 330 mm, is hardly worth thinking about, 2.5mm in radius is not going to make any difference. My kit also keeps the rear caliper and handbrake. The front caliper I use therefore has piston sizes the same as the OEM calipers, and by using a similar sized rear, keeps the balance. David by going to 17" wheels, why not go for 343mm rotors too?

I agree that the standard brakes are OK, if cooled properly. The question is, what are the problems that people are feeling? More bite can be had with better pads. Fading can be reduced by cooling. I don't believe anyone has suffered fluid boiling, despite what I've heard.

I was always able to lock up the brakes on the track. The last time on a track (Spa) I was faster than I've ever been there (we are allowed timing for the Trophy), and I was using OEM pads! I was just driving better, and staying OFF the brakes more than anything else.

Tomorrow I shall find out if my brake efforts have been worth it, as they are ready to rock. I only have the fronts finished so far. I shall of course report back here.

[Kevin]

You know what we really need? A track day where all the track day regulars can see who is the quickest with whatever mods.

Go on, make that transition from track daying to racing, or at least sprinting.