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Today at Atelier Kaz - Private NSX Enthusiast, ex-Honda R&D engineer with F1, Indy/CART background

ABS Upgrade 01

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Started to work on another NSX.

The service menu is to upgrade the ABS from
the original classic one and the Health Check.

This NSX is heavily modified and mainly used for track day only so
lots of nice aftermarket parts are somewhat obstructing the process.

Normally, I prefer carrying out the test driving session first before
touching anything then wash the wheel arch before starting the service.

However, with the recent snow,
I didn’t want to risk driving this precious NSX so
started removing the parts.

It has tiny racing battery and being told that
when the engine is warm,
the engine will start fine but when it’s cold,
it will require the support of big jump battery.

I noticed that the voltage reading on the dash was
only about 13V when the engine was running.
It has FI modification so the ACG is mounted using
different method and looked to be from another
model (Prelude??) so not sure whether it is spinning at
high enough speed or not at idle rpm.







Another concern was the state of cables, coolant pipes and
hoses around the battery area.

In order to install the intercooler tank at the
front compartment and also the battery cut off switch,
several parts were modified and stressed.

Poor battery GND cable at the chassis GND point....

It was sharply bent and overstretched.








Some sort of battery conditioner terminal and cable that
even the owner didn’t know.
The eyelet was nearly destroyed.
The owner is happy for me to remove it.



The battery terminal clamp was very loose on
both Posi and Neg posts.
Because they were loose, the internal wall of clamp was
already showing the patina (green like coating) resulting in
higher resistance.
The clamp itself is made from cupper and
in order to prevent the oxidation,
it is plated in silver so very important to scrape off the
patina and then apply dielectric compound to prevent
further oxidation.







As mentioned many times,
it is important not to over tighten the clamp.

It is cupper so softer than the bolt and nut.
Unfortunately, this GND cable was beyond the repair.
The nut has chewed into the clamp and even using the
washer, I don’t think it can hold the terminal properly.

I do have new GND cable but that’s already reserved
for the next NSX in the queue.

As the owner may want to install different type of
battery cut off switch, we can install the
new GND cable and the switch during the next visit.











In order to pass the intercooler hose,
the aluminium pipe for the A/C heater was
kinked/bent in the wrong direction.

They should look like below....
Notice the difference???


















The proof of being used only on the track.

Very clean A/C evaporator despite the age of the car.






Already several aftermarket cables were installed and
passed into the cabin.







No idea why the cables were connected before
the fuse block.....
I hope they have their own fuse......








Just keep removing the parts.....



About to take out the original ABS unit.
More to follow later.


Kaz


Comments

  1. AU_NSX's Avatar
    Kaz,

    Is it better to upgrade the ABS system to later system or remove ABS completely from a track only NSX?

    Mike
  2. Kaz-kzukNA1's Avatar
    Hi, Mike.

    I don’t know the spec of your NSX or your background and I don’t have the time to read all of your posts on NSX Prime so my apology in advance if I’m repeating something you already knew…..

    No one can do anything beyond the performance of the tyre.

    ABS is only a part of the chassis setup/aid and it is only the driver who can make the decision on ABS with the input from the chassis engineer for the track dedicated NSX.
    There is no such thing as one best single setup for all NSX.
    Also, depending on the race regulation, you may not be allowed to use ABS.


    If you are professional driver and own the NSX-R (02-R), you will be able to extract the characteristic of NSX-R ABS combined with NSX-R chassis setup on track.
    Some owners went further and added the aftermarket brake bias adjuster inside the cabin for track only NSX.
    You can use NSX-R ABS on the standard NSX but it won’t be the same result because the software is based on the 02R chassis setup/components to start with.
    So many different factors such as chassis setup, corner load, brake booster, etc, etc, etc.

    Personally, if you are driving your NSX to/from the circuit on the public road, I will recommend you to keep the ABS and ideally, upgrade it to the latest spec.
    If you are still using the classic ABS, you can easily disable it for the track session.
    Then, before leaving the circuit, just erase the error code to recover the classic ABS.


    The biggest factor will be the driver skill, tyre, brake balance, corner load and track Mu/shape/condition/etc.
    I won’t go into too much detail regarding the above factors because it’s going to take long time.
    Instead, I’ll share my experience.

    With the classic ABS, the biggest problem is the fact that it’s a standby pressure system.

    What I meant is that it relies on the high pressure fluid stored inside the accumulator.
    Therefore, the ABS is only available for the amount of high pressure fluid left inside the accumulator.

    As you may have noticed, the ABS pump won’t pressurise the system even after you activated the ABS one or two times.
    This means that you lost a certain amount of time that ABS could operate the next time when you triggered the ABS.

    I experienced scary moment on both the street and track where I lost ABS operation because of the above reason.
    ABS operated for a fraction of second but then the pedal felt as if it sunk with no more kick back at the pedal. Yet, the ABS pump was making that squeaking noise at that time trying to recover the lost pressure.
    The professional drivers are ‘human ABS’ and they can release the brake pressure by themselves under this kind of condition but not average driver like me.

    Later, I tested this on the skid pad and confirmed that if your ABS was triggered previously without the ABS pump topping up the fluid inside the accumulator, you could loose the ABS when it was operated next time.
    This was despite the fact that the pump activation pressure threshold was extremely high and even with the perfectly fine classic ABS.

    You can do similar test on snow covered long down slope.
    Activate the ABS two times and on next activation, keep pressing on the brake pedal and eventually, you will notice that there is no more kick back and pedal feels as if it sunk down. At that point, the ABS pump is screaming to recover the lost pressure inside the accumulator.


    The control of the classic ABS is primitive and it created massive ‘ABS understeer’.
    Addition to this, the brake balance with early model brake calipers were too much towards the front.

    Enter the corner at high speed and while keeping the same steering angle, apply hard braking to activate the ABS.
    With the classic ABS, the car just kept moving outward. Again, the professional drivers can adjust the brake pressure and recover the steer.


    On the other hand with the upgraded ABS, it’s a completely different story.
    The ABS pump will kick in every time when you activate the ABS so unlike the classic ABS, its operation is infinite.

    The brain power is far superior than the classic one so that it can provide faster reaction and more detailed control. You can even feel the big difference in the kick back at your brake pedal.

    One of the biggest benefit is the fact that you can change the direction of the car even during the ABS period. You can now on purposely use ABS on track,
    No more ABS understeer that was inevitable on the classic ABS.


    Having said this, the upgraded ABS is nothing special.
    We just caught up with rest of the ordinary production cars on the street.
    It just shows the classic ABS was such an ancient system.


    At the end of the day, it is the driver who makes the car go fast.

    On many car forums, people talks about what the alignment should be, the camber change by the control arm under load, etc, etc.

    I was fortunate enough to be in the driver/passenger seat of special cars with some of the best drivers in the world and one thing common to them was they were all very smooth.

    One of the driver owned NSX and he took me in his NSX one day.
    His NSX was in very poor condition with worn out tyre, completely wrong alignment, broken ABS, etc but still, he was very smooth and much faster than amateur drivers.
    While driving, so many factors change dynamically and continuously.
    Also, the car itself won’t be the same towards the end of the race session compared to the state at Lap1.
    Good drivers can adjust their driving style depending on the state of the car.


    Hope above info will assist you in making your own decision.

    Kaz

    Updated 27-01-2013 at 12:55 PM by Kaz-kzukNA1 (typo, etc)