Tracking the stock callipers

[sparky]

How many of you track-day NSX enthusiasts are using stock calipers, either with stock or oversized rotors? Are the stock calipers up to the task?

I've driven various modern Porsches with their superb four-pot brembos and they were extraordinarily capable and resilient brakes, especially as the number of laps climbed. So I'm a bit dubious that the NSX "one-sided" calipers / stock rotors can do the job. On the other hand they are very light , so if the consensus is they're up to the task I might give them a go before lashing out on expensive 4-pot calipers.

 

[stuntman]

The stock calipers aren't really that light.

For what application? FI or ~stock power?
~stock weight or lighter weight?
How advanced of a driver are you/how hard will you actually push it the car to its capabilities?
Street with occasional track use, or just track use?
What tires and what size front and rear?

I've tracked my ~stock powered NSX on aggressive street tires quite a bit and with good pads and fluid it was more than capable for 30 minute sessions (1992 car). Performance Friction should be coming out with their "06 compound" streetable track pad which should be awesome, i'm really looking forward to trying those out.

 

[sparky]

The stock calipers aren't really that light.

Interesting ... I must weigh them!

For what application? FI or ~stock power?
~stock weight or lighter weight?
How advanced of a driver are you/how hard will you actually push it the car to its capabilities?
Street with occasional track use, or just track use?
What tires and what size front and rear?

Billy, I'm "quite experienced" ~ 20 years of sporadic club level events and a few major tarmac rallies (but not in my NSX, yet). So I know what it's like when,on lap 6, I try to brake 3 yards later than my last marker ... and overshoot the apex But I don't extend myself to door-to-door racing.

It's a "track focussed street legal" car. No FI but a few of the usual tweaks like GTLW exhaust mean I have a bit more than stock power. Weight is down around 2750 lbs and falling. Tyres will be R-spec track tyres, possibly even slicks if I can fnd the sizes, on 17inch Rays CE28N lightweight rims...

 

[stuntman]

Interesting ... I must weigh them!

Billy, I'm "quite experienced" ~ 20 years of sporadic club level events and a few major tarmac rallies (but not in my NSX, yet). So I know what it's like when,on lap 6, I try to brake 3 yards later than my last marker ... and overshoot the apex But I don't extend myself to door-to-door racing.

It's a "track focussed street legal" car. No FI but a few of the usual tweaks like GTLW exhaust mean I have a bit more than stock power. Weight is down around 2750 lbs and falling. Tyres will be R-spec track tyres, possibly even slicks if I can fnd the sizes, on 17inch Rays CE28N lightweight rims...

I was right at the limits of acceptability of tracking my car:

2800lbs (with me and a passenger = 3,150)
235/265 RE01R Bridgestone tires
Headers, test pipes, GTLW exhaust
KW V3 coilovers
NSX-R wing.

I think because of the choice in R-compound tires (and especially slicks) you might just be over the capabilities of the stock brakes. Anything less than that I would probably say the stock system is probably adequate for 30minute sessions.

How long are your sessions? What size R-comp/slicks?

 

[sparky]

Thanks, that gives me good reference point.

I'm considering at these 4-pot calipers on front on oversize rotors front and rear: RacingBrake NSX front oversized 4-pot kit

What do you think of them? They look the goods to me ... specs are right, but I was dissapointed when I learnt the pistons are all 38mm. In my experience the best multi-pot brakes (e.g. brembo) don't have equal sized pistons, and this compensates to avoid extra / uneven wear on leading edge of pad, compared to trailing edge (or maybe vice versa, I can't recall).

 

[SFNSXguy]

I've found the stock calipers more than adequate for regular "track day" events -- you won't be able to late-brake into the corners the way you can with upgrades, but you'll do just fine.

I have upgraded the discs (drilled BBS) removed the dust plates and added Dali air scoops. Don't forget to use some decent brake fluid (I like the Motul 600).

 

[sparky]

I've found the stock calipers more than adequate for regular "track day" events -- you won't be able to late-brake into the corners the way you can with upgrades

hmmm, late braking is one of my favoured techniques. If the difference between stock and 4-pot is that obvious, I will go for the 4-pots every time.

 

[docjohn]

tracking with stock brakes is an evolution,you tweak them up untill you have outdriven all the tweaks.It would not cost too much to just do all the tweaks and run and see if they are up to your driving and track configurations.Your local track will be a big determining factor in your brake function.The front ducting can be done two ways cut into the dust shield ala Ken Sax or just remove them(shields) and run the tubing into a larger brake deflector like ..dare I say the Dali one.

 

[sparky]

Your local track will be a big determining factor in your brake function.

It's a short track renowned for it's demand on brakes due to three hairpins at ends of straights, so 3 heavy stops from high speed per lap

The front ducting can be done two ways cut into the dust shield ala Ken Sax or just remove them(shields) and run the tubing into a larger brake deflector like ..dare I say the Dali one.

I've already fitted larger deflectors, from a Porsche 993. But what are the dust shields you refer to? If they the thin metal stone shields behind each rotor I've removed them too. I still have air-con units in front fenders so it doesn't look like enough room for any sizeable ducting?

 

[R13]

I've run HP+ pads (the same set incidentally) in stock calipers for two days at Talladega GP (a short track that's really rough on brakes as it does not provide much time for cooling the brakes between when you have to make pretty heavy use of them), and I just completed a 3-day weekend at VIR. I have no additional ducting and the stone shields are still there (for now).

1992, stock motor, DT-S tailpipe, Dunlop Z1s

I'm good enough to use the brakes to their full extent most of the time,but I have not experience any fade or pad glazing, so far. The rotors (of unknown age and mileage) have begun to spider-crack (i.e. little cracks that indicate they're not long for the world) after this use. I plan to look into some more substantial ducting to hopefully extend rotor life a bit.

I agree with Doc. You'd probably be fine to do a weekend with good pads, fluid, and cooling to see what you think. beyond that, do whatever is going to make you comfortable.

 

[pgilliam1]

Upgrade the brakes - they are this cars weak spot -IMO.

Happy Motoring!

 

[NSXDreamer2]

I'm in advance at my local track, I believed different tracks have different brakes "requirement".. For many years, I've been agreeing with nsxtasy's formula of stock caliper, upgraded pads. (I love the carbotech stuff, though through the years I'm going from Ax6(panther+), XP8, Xp10) along with Stoptech aero rotors. (stock size.)

I can't say myself being fast guy, but I run lap times identical to the fastest group at most HPDE despite they have bigger hp and "better car".

Not until lately, I found that some tracks are way more demanding on brakes than my local track. Heat seems to be the problem of the nsx system, (rather than balancing or bias). NA1 ABS seems to do pretty bad job at wet. Threshold braking as if you don't have ABS.:biggrin:

I have to say the stock brakes on oem are way better than many other newer cars with big brakes. Or BBK on other cars.. (not because of the brake hardwares itself but the balanced chasis of the car.)

Like someone suggested, just do the cheap mods... (which is, no oversize rotors.) and if they failed, upgrade to the tried and true stoptech, brembo, ap racing bbk.


Sorry Billy, Performance Friction is quite expensive and it, along with Indy Brembo, should be the ultimate setup; but not the next step. IMO.

 

[sparky]

It seems no-one is using RacingBrake calipers? Perhaps they're not in same league as AP racing, brembo etc?

 

[Hrant]

It seems no-one is using RacingBrake calipers? Perhaps they're not in same league as AP racing, brembo etc?

As the other said, try your brakes with good track pads or even street/track pads, with with some added cooling, Motul brake fluid and see what happens. I helped design the first fitting of the RB two piece rotors for the NSX and used them for some 20 track days. They held up well and helped in cooling the rotor temps by about 100F and that was sufficient for my needs.

Since you have some track experience, you will soon appreciate that often the tires are the limiting factor and not the brakes. Now, if your NSX has FI, then a 4 pot and larger rotors would help. And once you decide to upgrade, there will be more opinions than the number of brands available :wink:

 

[asylum]

First make all the upgrades you can on the stock brakes (fluid, pads, lines, cooling) because they are cheap to run. You will be surprised how good they are. And if you think you are using the full potential of the stock brakes, you are either experienced or mytho enough to go with a BBK :biggrin:

 

[Tamar]

Brakes just slow you down! :biggrin:

 

[nsxtasy]

Yup. I've got over 13,000 actual track miles on my NSX in the twenty years I've owned it (as well as an even higher number of track miles on other cars), and I still have the original calipers on it. As noted above, I have installed 2.5" air ducts running from the front air dam, over the core support alongside the lower corners of the radiator, to flanges welded onto holes cut in the front dust shields (yes, the thin metal stone shields behind each rotor). I use R compound track tires and an assortment of street-track brake pads such as the Hawk HP+. (You can get various track pads if you like for greater friction, but they typically squeal on the street and/or don't work when cold, and I'm willing to sacrifice a slight amount of friction in exchange for not swapping my pads before and after events and not having those downsides on the street.) I've mostly used Motul RBF 600 brake fluid and recently upgraded to Prospeed 683.

I've never felt the need to upgrade my calipers. My brakes don't fade except when the pads are being used for the first time ("green pad syndrome"). Now that I religiously bed new pads, I don't have any other ill effects from heat buildup, except that the front rotors eventually start to crack after a while, but that can happen even with big brake setups. Another advantage of the stock caliper setup is that I can use 15"/16" wheels for my track tires, and they fit inside the car so I can drive to the track on my street tires.

I'm not saying that there is anything wrong with upgrading calipers and rotors, but there are significant downsides that go with doing so, particularly the cost. I don't know whether or not pad availability is an issue with any of these setups, either.

I agree with the advice above, under the general philosophy of upgrading only when you find that you actually need it. Try tracking with the stock calipers first, with good fluid and good, properly bedded pads (track pads if you like). Don't get upset if they fade the first (or second) session you use the pads. After that, if you find that you need greater braking or greater resistance to heat, you can consider upgrading to bigger calipers and/or rotors. But it's quite possible that you won't need to do so.

HTH

 

[stuntman]

Sorry Billy, Performance Friction is quite expensive and it, along with Indy Brembo, should be the ultimate setup; but not the next step. IMO.

Maybe I should have been more clear. Performance Friction is coming out with their awesome "06 Compound" streetable track pad (well an endurance race pad thats streetable) for the STOCK nsx caliper.

Sparky, maybe try these pads with your stock calipers and see if you can run into a fading issue. If you do, then you can always upgrade the front setup to like a Brembo 4 piston "Lotus" caliper that is relatively inexpensive.


Billy

 

[sparky]

thanks all, you've sold me on giving the stock calipers a thorough thrashing and seeing how they stand up.

now where else can this happen but on Prime? :smile:

 

[jtower]

Maybe I should have been more clear. Performance Friction is coming out with their awesome "06 Compound" streetable track pad (well an endurance race pad thats streetable) for the STOCK nsx caliper.

Sparky, maybe try these pads with your stock calipers and see if you can run into a fading issue. If you do, then you can always upgrade the front setup to like a Brembo 4 piston "Lotus" caliper that is relatively inexpensive.


Billy

pcf06 pads are fabulous, i run them on my overweight, stock brake e30 race car and have never experienced fade, even at brake brutal tracks like cmp.

 

[latzke]

First make all the upgrades you can on the stock brakes (fluid, pads, lines, cooling) because they are cheap to run. You will be surprised how good they are. And if you think you are using the full potential of the stock brakes, you are either experienced or mytho enough to go with a BBK :biggrin:

Sparky, maybe try [performance friction "06 Compound] pads with your stock calipers and see if you can run into a fading issue. If you do, then you can always upgrade the front setup to like a Brembo 4 piston "Lotus" caliper that is relatively inexpensive.

thanks all, you've sold me on giving the stock calipers a thorough thrashing and seeing how they stand up.

Since you're heading down the stock caliper path I wanted to emphasize the impact/importance of pad compounds.

About a decade ago I got a lot of track time in my 1991 NSX w/ CTSC (but at altitude, which takes some power back) on wider-than-stock R compound tires. I found the stock brakes (without ducting/deflector or removed shield) to be adequate for full sessions when I ran RM Racing's "race only" pads which later research (calling Hawk and then calling the intermediary they said sold to RM) leads me to believe were re-branded Hawk DTC-70 (front) and DTC-60 (rear) compounds. Once you got them warm...wow...if you took them on the street cold...eek (and squeak).

Currently (with more boost, short gears/R&P, still no ducting/deflector or removed shield, and RT-615 street tires in stock sizes) I run Hawk HP+ pads and have not found their feel to hold up as well, despite the lesser tires and a little milder driving on my part. Once the feel starts to change I've not pushed them farther to see if/how well they hold up beyond that point (I still have plenty of fun while dialing it back / taking a mid-session cool-down lap to "give the brakes a break"...says the aging fellow).

Anyway, what I'm getting at is...

Someone serious about maximizing the stock brakes (before making the jump to bigger brakes) I think would have to not just deal with the fluid (RBF600) and cooling (remove dust shield, add deflector) but also run track-only pads at the track (swapping pads before/after track days if the car is to be run on the street). Especially without FI and added downforce I would certainly try the Performance Friction 06 compound Billy and jtower recommend (and maybe others track/race pads) before coming to the conclusion that you've maximized the stock brakes and found them inadequate.

 

[TXvsLV]

or just call Carbotech directly (877)899-5024 .... chris and I run their pads daily and just deal with a little squeal!!!

best fluid is the Castrol, but $70 a bottle...and worth it

 

[whitebois]

I just finished upgrading to RB al 4-piston front calipers and 320mm disks front and rear on a 91. I also upgraded the caliper brackets so I did not have to mess with the parking brake. RB provides stainless lines as part of the kit. I also have a Boxster S with amazing stock brakes on it- when you are driving it you know you cannot get in trouble because the brakes are so strong and full of feel. The old NSX stock rotors are way undersized and had a dead feel. With the upgrade, the NSX now brakes more like the boxster with the big brakes- it is like night and day in my opinion-not even close.

 

[stuntman]

I just finished upgrading to RB al 4-piston front calipers and 320mm disks front and rear on a 91. I also upgraded the caliper brackets so I did not have to mess with the parking brake. RB provides stainless lines as part of the kit. I also have a Boxster S with amazing stock brakes on it- when you are driving it you know you cannot get in trouble because the brakes are so strong and full of feel. The old NSX stock rotors are way undersized and had a dead feel. With the upgrade, the NSX now brakes more like the boxster with the big brakes- it is like night and day in my opinion-not even close.

The stock NSX calipers are still adequate for NA track use when using the proper pads with enough initial bite. It all depends on the intended use, application, and severity of driving conditions.


Billy

 

[MvM]

I just finished upgrading to RB al 4-piston front calipers and 320mm disks front and rear on a 91. I also upgraded the caliper brackets so I did not have to mess with the parking brake. RB provides stainless lines as part of the kit. I also have a Boxster S with amazing stock brakes on it- when you are driving it you know you cannot get in trouble because the brakes are so strong and full of feel. The old NSX stock rotors are way undersized and had a dead feel. With the upgrade, the NSX now brakes more like the boxster with the big brakes- it is like night and day in my opinion-not even close.

You are the FIRST person I read about who upgraded the brakes using the RacingBrake calipers as well as their rotors.
Would very much like to see some pictures of your setup.
Also, what wheels are you running and what offsets?

In your case, you upgraded BOTH the calipers and the rotors. I just upgraded the rotors (324mm in front, stock 97 size in the rear) and pads (Hawk HP+ or HPS) and found that just those upgraded already made a night-and-day difference.