DIY low budget brake upgrade

[nsxnut]

Larger piston diameters might also lower brake fluid temps slightly (at least localized heat at the piston surface). Call it distributing the energy lost as heat to more fluid through the larger surface area.

Thinking about this I suspect this effect is minimal but larger boar will reduce the thermal mass of the caliper. Reducing the thermal storage capacity increasing fluid temp. Again most likely minimal effect.


Later,
Don

 

[M-P]

Thinking about this I suspect this effect is minimal but larger boar will reduce the thermal mass of the caliper. Reducing the thermal storage capacity increasing fluid temp. Again most likely minimal effect.


Later,
Don

Interesting thought. Less thermal storage would hinder sequential braking events, while more piston surface area would help a single braking event...even if the effects of both are too small for anyone other than an F1/Endurance team to notice.

 

[NSXGB]

Front NA2 40 + 32 mm pistons

FYI....NSX '97+ front brake calipers have 40mm & 34mm pistons not 40 & 32mm.

I would personally not interfere with brake bias for a street car.
I'm not sure I agree with the argument that "ABS will correct an improperly-balanced setup".

 

[NSXGB]

FWIW, my recommendation for a "budget" brake upgrade from '91-'96 spec brakes would be;

(Assuming you're running 16" wheels up front min)

Racing Brake caliper brackets;
http://www.racingbrake.com/Caliper_Bracket_NSX_REAR_91_96_Upgrade_p/cb08.htm
http://www.racingbrake.com/Caliper_Bracket_NSX_FRONT_91_96_Upgrade_p/cb07.htm
With the rotors of your choice in '97+ sizes & longer braided hoses.

 

[nsxnut]

I'm not sure I agree with the argument that "ABS will correct an improperly-balanced setup".

Your right abs won't make up for bias problem.
If the bias is off and the front brakes lock up sooner than they normally would.
Stopping distance will be greater than if the bias was perfect and all wheels locked up at the same time.

 

[gabedm]

Correct.


MvM,
according to my calculations...
40+36 = 76

76mm is your total diameter equalling a surface area of 4536.46mm

from an engineer, this gets post of the year! LOL

 

[Mac Attack]

Your right abs won't make up for bias problem.
If the bias is off and the front brakes lock up sooner than they normally would.
Stopping distance will be greater than if the bias was perfect and all wheels locked up at the same time.

No, it will to a point.

Each wheel has a speed sensor. The computer detects relative angular velocity of one speed sensor and compares it to the other three at a given sampling frequency. Because the tire diameter ratios front to rear have been given a tolerance, the computer knows which wheel has more or less traction by how fast it is spinning relative to the others.

This method compensates for tire friction differences, brake pad differences, etc.

Now, it can only compensate to a point and is limited by how fast each brake solenoid can pulsate. If your bias is really screwed up, then ABS may not be able to compensate.

Of course, having a system that is off-balance would mean that the ABS is constantly kicking in to try and maintain effective braking. This would obviously be a PITA trying to drive on the street or track. I'm not saying it's OK to slap an improperly-designed system on these cars, but if you have to, the ABS should be able to compensate for some.

Dali's website has a wealth of knowledge for us to compare the various NSX braking progressions and get an idea of a good starting point when trying to calculate ideal braking setups for individual use.

Dave

 

[angus]

No, it will to a point.

Each wheel has a speed sensor. The computer detects relative angular velocity of one speed sensor and compares it to the other three at a given sampling frequency. Because the tire diameter ratios front to rear have been given a tolerance, the computer knows which wheel has more or less traction by how fast it is spinning relative to the others.

This method compensates for tire friction differences, brake pad differences, etc.

Now, it can only compensate to a point and is limited by how fast each brake solenoid can pulsate. If your bias is really screwed up, then ABS may not be able to compensate.

Of course, having a system that is off-balance would mean that the ABS is constantly kicking in to try and maintain effective braking. This would obviously be a PITA trying to drive on the street or track. I'm not saying it's OK to slap an improperly-designed system on these cars, but if you have to, the ABS should be able to compensate for some.

Dali's website has a wealth of knowledge for us to compare the various NSX braking progressions and get an idea of a good starting point when trying to calculate ideal braking setups for individual use.

Dave

Dave, I've actually driven cars with mis-matched brakes and let me tell you - the ABS does not even come close to compensating.

It still upsets the balance of the car in a bad way and it is so abrupt when the ABS intevenes - you might as well not even have it.

I would not want that.

 

[Mac Attack]

Oh yeah, as I acknowledged in my last post, having the ABS kick in constantly near threshold braking limits would be pretty bad, especially with our slow archaic ABS modulator.

I guess on the street though before you have ABS actuation, then it could also cause some unnerving moments during moderately hard braking.

My reference to the ABS compensating was only for "benign" changes like going to a Legend caliper instead of the NSX caliper.

I would never slap a BBK on just the front or the rear of our cars.

Actually, I removed the ABS/TCS on my DD NSX over a few years ago.

Dave

 

[NSXMitch]

Great read from a new NSX (VERY happy new owner - love it) owner looking to upgrade his NSX brakes.

I'm a long time Porsche owner - I've owned six over the years, and have gotten used to having pretty strong brakes. So far, my impression of the (mine's a '98) NSX's in comparison is that they are only adequate for street driving. Particularly in light of owners upgrading power and handling to capabilities of modern exotics...

Gulping as much info (from Prime and Vendor's info..) as I can read, here are some impressions:
- many owners are afraid to change the bais F to R
- Most of the Track drivers WANT to change to a Front bais
- In order to go to "Bigger" Brakes (larger calipers AND rotors) and keep the same bais, you pay around $3K for rear BBK (more for an E brake) for that piece of mind

As per the specs above the factory NSX calipers are very similar front to rear - speaking at rotor diameter / piston size / pad size - VERY similar, i.e., virtually identical...
Same size calipers front to rear is counter to most if not all performance car designs (Porsche, F-car, Aston, etc). All have much larger calipers up front. Some will say "It's a mid-engine car with near equal weight bais..", which is true - but the majority of ANY car's braking force is always accomplished by the front tires (brakes). In my mind, that means more brakes are needed up front.

Now to my question for those posting here:
How about putting the Calipers from the front of the Legend on the rear of the NSX combined with a BBK up front?
You could go from:
NA2 Rear@ 48mm: Total Surface is 1810 mm2 to Legend@ 42+38mm: Total Surface is 2520 mm2. Even at the corrected numbers, that is around 50% improvement.

Use the largest (NA2 rear 303x23mm) rotor / diameter and combine THAT with a front only BBK (say, Brembo / Stoptech / ?)...

Couldn't that give you a BBK in front with improved rear (not such an extreme bais change) and be much cheaper than buying BBKs front and rear?

Not exactly low budget, but better than $3K for an extra BBK (rear) to retain some rear bais...

Apologies if I'm way off base... I'm new. :redface: