ALB-ABS generations

[warrenw]

are there different generations of the ALB-ABS modulator.
From 1991 there was one specific type did it change again before 2000 and if so when.

thanks.

[NSXGB]

Yes, there are 3 different generations, take a look in the blog, info and pictures available courtesy of Kaz.

[Sudesh]

are there different generations of the ALB-ABS modulator.
From 1991 there was one specific type did it change again before 2000 and if so when.

thanks.

Yeah the early cars had 2 types, kinda look similar but when compared to each other you will see the difference. The later ABS looks completely different and easy to distinguish.
The change from say generation one, to generation 2 was around 94 I believe.

If the original label is still on your ABS reservior, and it's yellow in color, it's generation 1; if the label is white, it's generation 2, that's provided someone hasn't changed them at some point.

[Kaz-kzukNA1]

Hi, warrenw.

Please note that following information is mainly based on the RHD model so the photo and the info would be different for LHD ones.

[Edit: By the way, I noticed that you have used my photos and information below on NSX Prime for your 'ABS/ALB modulator rebuild write up'. While I don't have any issues with it as other members on Prime are doing the same but it would be nice if you can include the source of information was from NSXCB. You have included it in the ver.4 of your pdf file but not on the actual post above.]


You can find the photo and info in the ‘Brake’ section of my ‘NSX Technical and Service Information Index’ thread under ‘Technical’ forum.
It is titled as ‘ABS History’ and the direct link is as follows;

http://www.nsxcb.co.uk/showthread.php?6286-NSX-Health-Check-Service&p=75279 - post75279 (http://www.nsxcb.co.uk/showthread.php?6286-NSX-Health-Check-Service&p=75279#post75279)



From outside, the obvious difference is the shape of the reservoir.

The original 1st generation one is like a plain square/cubic shape.
The 2nd generation one has protrude section at the reservoir.

Again, please note that these photos are from RHD model although it would be similar for the LHD one apart from the mounting direction and pipe fitting angle.


This change was made around 91 – 92 depending on the country spec so not 100% sure on when it was introduced for the LHD market.
For US Acura, probably around 92???


Internally, the package design of solenoids were changed dramatically between the 1st and 2nd generation ABS because of the famous leaky solenoids issue.

While all four solenoids were installed separately on the 1st generation ABS, two solenoids were packaged into a single module for the 2nd generation one and thus, instead of individually installed four solenoids, you will see just two big solenoid blocks mounted on the latter model.


Strictly speaking, the 2nd generation ABS actually has two different types as well when you consider the brake bias although you won't be able to tell the difference of the ABS unit from outside.
So, there are four different ABS during the production of our NSX.


One of the most strange yet understandable design on our NSX was the brake balance and chassis setup on the early NSX models.

It was too much to the fronts and compared to other midship sports cars, you feel like your body wants to go forward instead of being squashed down to the ground.

Later, Honda acknowledged this and shifted the brake balance much more towards the rear.
This is when the larger brake calipers/discs were introduced and at the same time, ABS tuning was changed to meet the modification in the brake balance.

The piston springs inside the ABS modulator was changed to shift the ABS point for the modified brake balance and also the ABS computer software was modified although I heard that the changes in software was more to do with ABS circuit and diag code revision.


Kaz

[warrenw]

Thanks everyone for the reply.
Kaz: I referenced the picture source. Let me know if I need to do more. Thanks, as well, for the ABS-brake explanation. You carry outstanding knowledge about these cars.
Is it possible that the 2nd generation modulator is UK or Europe specific. I checked the part number reference for years 1991 - 1999, and the modulator part number does not change in North America.

[Sudesh]

Strictly speaking, the 2nd generation ABS actually has two different types as well when you consider the brake bias although you won't be able to tell the difference of the ABS unit from outside.
So, there are four different ABS during the production of our NSX.

Kaz, does include the NSX-R? Or with the NSX-R does it mean there are 5 types? I know NSX-R is not a main stream car like the standard NSX, so not included in some comparisons like this, plus it's JDM specific; but just interested to know to add to my own knowledge!

[Kaz-kzukNA1]

Hi, warrenw.

Thank you for adding the reference info in your document as well as on the post on NSX Prime.
It’s for the n-etiquette (internet-etiquette).



...........................
Is it possible that the 2nd generation modulator is UK or Europe specific. I checked the part number reference for years 1991 - 1999, and the modulator part number does not change in North America.

The US Acura NSX (haven’t checked HK Acura one) did change its ABS modulator in early 90’s.
I don’t like the idea of using the ‘year model’ as the definition is different from country to country and I prefer using the first several characters of VIN instead.

I know from which VIN the ABS modulator was changed to 2nd generation for UK and JDM NSX but not for the US Acura so I can only reference it with the year model.
93 US Acura NSX was already using 2nd generation one so it seems that the changes were made from the beginning of 93 model or some point for the 92 model.

Again, you can distinguish it by the shape (with/without the protrude) of the reservoir.


For your reference, in US, you can buy all of the O-rings for the solenoids but not the ones for the piston (referred as ‘valve’ in your pdf document) from Acura dealers.

In Japan and possibly in UK, we can buy all of the required O-rings from Honda dealers.


While the O-rings at the piston are the same between the 1st and 2nd generation ABS, the ones at the solenoid are not.


I noticed that in your pdf document, it seems that you are using two different O-rings that go around the piston (valve) body.
The OEM spec uses the same one for both O-rings.
The two O-rings in your package seem to have almost identical diameter and exactly the same thickness so hope they are fine.

Hope your project will save some of the classic ABS on the market as upgrading to the latest design is quite expensive these days unless you source the modulator and upgrade loom from Japan.


Kaz

[Kaz-kzukNA1]

Kaz, does include the NSX-R? Or with the NSX-R does it mean there are 5 types? I know NSX-R is not a main stream car like the standard NSX, so not included in some comparisons like this, plus it's JDM specific; but just interested to know to add to my own knowledge!
Hi, Sudesh.

As always, good point.


In fact, that makes 6 different ABS setup at least.
Addition to the 4 types mentioned above, there are two additional spec as follows.


NA1 Type-R was introduced as NA1-110 type in Japan from Nov/92 but stopped its production before the introduction of larger brake caliper size so it falls into the 2nd generation early spec ABS era.

It had the same software (ABS controller) but different piston spring setup inside the modulator compared to the standard 2nd generation ABS.
It had the same brake master cyl and brake booster setup as others but as we all know, it was equipped with different brake pad, suspension setup, chassis weight distribution, etc so not easy to make comparison.


NA2 NSX-R is bit more complicated.
By the time it was introduced in May/02 as LA-NA2 140 type, all ABS was upgraded to the 3rd and final generation.

It went for the Bosch style solution to combine the modulator and controller software in a single box.

The ABS setup is quite different from the rest of the models and it should be mentioned together with the huge increase in power assist from the different spec brake booster pack.
It also requires NA2 NSX-R specific brake master cyl due to different mounting design.


Kaz

[warrenw]

Kaz, I don't think anyone in N. America have the part numbers for those o-rings you are referencing. Hence, the kit I put together. If you have those part numbers to share, that would be helpful for everyone. I asked an Acura/Honda dealer, and they just sell the entire modulator for $5500.00 USD.

[Kaz-kzukNA1]

Hi, warrenw.
Please refer to the following.


[Diagram no.]: [Parts no.] x [Quantity] ; [Parts name] ; [Brief description]


29: 57202-SB0-801 x 10 ; O-ring, Solenoid ; two for the reservoir + two for each solenoids.

15: 57139-SB0-801 x 6 ; O-ring, Divider ; two each for FL & RL solenoid + just one each for the rest

9: 57118-SG0-801 x 4 ; O-ring, Head ; sits above the piston once it’s installed in the housing

14: 57129-SB0-801 x 8 ; O-ring, Sleeve ; two that go around each piston body


Kaz





https://lh5.googleusercontent.com/-sBaAJNZVSok/UDNYFFxB-_I/AAAAAAAAEYE/uAhCLpuZoTA/s800/1stABS.jpg

[warrenw]

I noticed that in your pdf document, it seems that you are using two different O-rings that go around the piston (valve) body.
The OEM spec uses the same one for both O-rings.
The two O-rings in your package seem to have almost identical diameter and exactly the same thickness so hope they are fine.

Hope your project will save some of the classic ABS on the market as upgrading to the latest design is quite expensive these days unless you source the modulator and upgrade loom from Japan.


Kaz

Kaz, if you notice in the attached picture, the two o-rings are the same size (factory). Also note how much more one is stretched than the other. You will have to zoom in on the picture to really see it. (hence the slightly larger o-ring.) I noticed this rebuilding a modulator.
Thanks for the Honda part numbers. It seems Honda N/A does not want to sell some or all of these. I have a parts guy digging for me to see if there is a history of these part numbers. There now may be world wide supply, instead of just N/A - Japan.
http://www3.telus.net/public/warshan/Cars/NSX/ABS/P1010717.jpg

[warrenw]

I got word back form Honda parts
57202-SB0-801 are available
57139-SB0-801 are available
57118-SG0-801 is not a valid Honda P/N
57129-SB0-801 is not a valid Honda P/N

[Kaz-kzukNA1]

Hi, warrenw.

As in my last post, you can buy the O-rings for the solenoids (the first two parts no. in your post) but not the ones for the piston (the last two parts no. in your post) from Acura/Honda dealers in US.
Probably the same in Canada.


The last two parts no. are not even registered in their parts system so unless your parts personnel has access to the web based parts system for other region, the reply will end up as ‘not a valid Honda P/N’.


In UK, all four parts no. are registered but the parts system doesn’t have the ‘piston kit (#1 in my diagram)’ as a part and thus, if you try to place an order for 57129-SB0-801, you may get the reply as ‘not available’ or ‘discontinued’. You can compare my diagram against the one from Lings Honda website based in UK.
http://www.lingshondaparts.com/honda_car_parts_selection_pfk.php?block_01=17SL001&block_02=B__2411&block_03=21668


In Japan, all four parts are available but some of them may have long lead time as the demand is very low for overhauling the classic ABS.

Once you start experiencing the issue on classic ABS, people just upgrades it to the latest ABS in Japan based on the balance between the further cost for the accumulator failure, upgraded ABS performance benefit and the upgrade cost.

Kaz