NSX Standard brakes ??

[simonprelude]

OK, I booked the car into Chiswick to have the brakes looked at as I am not 100% on their effectiveness.

I am used to an S2000 with standard rear disks and pads but with Spoon front discs and pads.

Basically the NSX takes a lot longer to stop, say from 100mph.

The garage took the car out today, and I don't expect them to have replicated 100mph stops, but nevertheless have said that they can't see any problem with the brakes.

Now after watching BMI and seeing how they thrash the NSX and state no brake fade and how good they are, I am more than a little worried.

Right, I know the NSX is heavier than the S2000, but the calipers are supposed to be better, yes I have uprated discs and pads on the S2000 as well. But there is currently no way I would take the NSX to a track such as Donington as I would not be confident that the brakes would actually stop me.

Brakes visibly seem to have lots of life left, both on discs and pads.

Discuss................

NB I don't want uprated brakes, just want the standard ones to work.

[Rob_Fenn]

I cannot fault the NSX for brake feel, that is an area where it excels. Clearly Honda spent a lot of time trying to make every interactive element just right...but performance on track in terms of outright stopping power and longevity isn't good though.

My Dad and I have been through countless discs and pads on track, which is why the NSX is getting the AP Racing upgrade. I am slightly concerned that on the road you are finding it an issue though, that shouldn't really happen and it hasn't been an issue on ours.

A VFM upgrade would be higher temp rated discs (i never found any) with some Ferodo pads, better brake fluid and braided hoses. It would probably work out cheaper than OEM prices too!

-Rob

[modarr]

I must say the standard brake package takes a while getting used to. I thought I had faulty brakes when I swapped my Caterham for the NSX. Turns out, they just need a bloody hard squeeze to get the best out of them. This gives the impression that they are about to fail but isn't so. The pedal travel is excessive and the standard fluid/pads pants.

you may possibly be used to more highly servoed barkes needing less effort. I came from non servo brakes and still found the NSX brakes disconcerting to begin with.

[710]

My brake story, maybe the info will help.
I bought the car with OK/good Honda discs. Nice and smooth, a little worn, no juddering, braked nicely. I took the car to our annual mountain run in France. After I learned the car, I started to push it and the brakes started to fade. I could make them fade on the downhill runs. The brakes started to judder. By then the fluid had probably boiled too so I bled them as best I could considering we were on holiday… Tyres are S03s so softish.
At home I checked the discs, they are warped (usually caused by too much heat). The calipers are ok, they seem to work equally.
I saw the prices of Honda discs, had to sit down. So I ordered cheap ones (and an extra set too) from some place in Britain (£27 each? Or £19. I forget now).
After thoroughly changing the fluid with new normal fluid, I took it to the mountains and the same thing happened. But not any worse than with the Honda discs.
I checked with the garage that serviced the car before I bought it, they fit only Honda stuff so I assume the first set of discs were Honda (is there a stamp or something so I can check?). The pads are Honda stock.
So my conclusion is that the discs are too small for the weight of the car under extreme use. Actually in my opinion, ANY car’s brakes are too small for extreme use, the Cosworth ones ended up in the bin so fast it was a blur. Absolutely useless. With the NSX, it’s not so bad, though, they are not absolutely useless, just a little under sized. And I still enjoy the car a lot, I haven’t even made the time to install the big disc set yet! So it’s not THAT bad. Just my experience.
Peter

[UltraViolet]

No idea what that post above has to do with this topic... but hey.....

Simon - I agree - the standard brakes on the NSX IMO are not sufficient. Even for fast road use they are not great. In fact I thought it was a commonly held accepted point about the car. I think much better pads would help, but I don't yet have the experience to qualify that statement (still on OEM). Also whether that would be fine for road but still insufficient for track, no idea - but I guess you have a fair old wait while the warrenty expires before that is an issue anyway.

[mcibuk]

I don't take my car onto a track but in fast road use i'm always left thinking that the brakes could be better - physically the discs just look too small for the size of wheels and the weight of car. I'm still awaiting a reasonable price upgrade development that uses a slightly bigger disc on the fronts - nothing seen so far.

I know it's "off topic" but Khalid why didn't you give me that price last month - i would have bought from you then - too late now:x

[swlabhot]

IMO the oem brakes are crap. I'm gonna try just upgrading to fast road pads at next change and I'm expecting the bite to improve considerably.

[markc]

Without boring everyone with tails from my Porsche days, this braking issue used to come up over and over again....

There are very few if any road cars that have sufficiently large braking capacity to handle extreme braking for extended periods like those on the race track or in exceptional road conditions such as descending a mountain pass at high speed.

For example my old 993 Carrera was fitted with 304mm front discs (280mm rear) and 4pot Brembo calipers all round in a car weighing 1375kgs ie larger brakes than the NSX with only marginally more weight. Opinion was fairly evenly split as to whether this was adequate for track use or not.

Even specialist stuff aimed at the trackday market, such as the original Carrera GT3, has been found wanting for brakes in these conditions.

Driving style may also exasperate the shortcomings of a brake system ie on a circuit the same lap time achieved using late, hard brake application will cause less brake problems than early, long brake application! Same energy but more “off time” to dissipate it.

By very modern standards, a stock NSX setup is similarly found wanting in these extreme circumstances but I would suggest that some simple and relatively low cost "upgrades" can be employed to ensure that braking is as effective as possible, to the point that an extremely costly disc/caliper/wheel upgrade is largely unnecessarily. Unless of course you've added more weight (unlikely) or power (possibly).

All starting with bog standard kit.... make sure it's fresh and in good condition. Discs should be well within spec for wear (thickness) and the vents should not be clogged or blocked. Pads should be less than 50% worn and fluid bled, idealy replaced, before every track day.

To try to avoid warping discs it’s best to warm them up and down gradually, so some medium braking effort stops prior to maximum attack and more importantly a warm down lap with very little braking so that excess heat doesn’t get trapped between pad and disc when you eventually stop (heat soak).

Next comes cooling.... effective braking is ALL about dissipating the huge amount of heat (energy) generated by the brakes.

Most high performance cars use some form of air deflector to channel cold air to the discs/calipers. The standard fit deflectors tend to be small, made of plastic and are sized to ensure that they don't make contact with the average bumpy public road. If you're going to use the car primarily on a smooth roads or circuits, you can go for much larger and more efficient air deflectors such as the ones fitted by Darren (ctrlaltdelboy) prior to his A/C radiator removal and fitment of full CF ducting and employ ducting to force air over and past the discs/calipers.

From reports on NSX Prime and Kevin and Darren here, it seems that stock Honda discs and pads are about as good as it gets unless you are prepared to make significant compromises for road use (noise) or wear rates.

I’ve not had any problems on the road yet but am yet to take in any mountain passes and I guess I’ll find out about the on-track performance at Donington on the 14th Oct.

There's a good explanation of braking technology and the thermodynamics involved here if you're interested.... http://www.carbibles.com/brake_bible.html

Cheers

Mark

[markc]

This is a very good article with some actual temperature measurement taken to support the tests as well...

http://www.daliracing.com/v666-5/inf...des/index.html

[trackdemon]

Driving style may also exasperate the shortcomings of a brake system ie on a circuit the same lap time achieved using late, hard brake application will cause less brake problems than early, long brake application! Same energy but more “off time” to dissipate it.

Next comes cooling.... effective braking is ALL about dissipating the huge amount of heat (energy) generated by the brakes.

Sorry Mark, but I'll have to take issue with the comment about driving style - arriving at a corner and stamping on the brakes hard and late is a surefire way to destroy road car brakes in short order. Firstly, you're introducing a huge amount of thermal shock which road car brakes are simply not designed to cope with, a multitude of things can happen from cracking the disks to causing the pad stucture to breakdown ("normal" pad material is essentially held together with high temp bonding agent which can melt in extremis and build a layer of fluid between pad & disk).
Also, by using "maximum" braking force you are actually putting much higher peak energy through your disks & pads which will exacerbate wear and boil the fluid much quicker. I've driven my NSX very hard on track (trying to keep up with a much faster car ) using as much braking as I dare and generally cannot get any more than 3 "proper" laps out of it before backing off to cool the brakes.
Conversely, by applying the brakes early but gently I can run for 1 hour without any problems - I basically double my braking distance, applying the brakes very smoothly and progressively building the brake force until I get to my turn in point. Ultimately its a little slower over a lap, but it makes the brakes last several trackdays instead of 1......

The NSX is definitely defficient in the cooling area, whose idea it was to cover the caliper with silly plastic "protectors" which help to reduce airflow through the system obviously hadn't thought of track driving.... and easy mod, so ditch those if you haven't already!