Ok. So if we have tcs permanently disconnected then the pumps should work fine above?
I think a lot of people are interested in how this unfolds.
I think a lot of people are interested in how this unfolds.
ABS or No ABS
- Thread starter Stephen@NCAutoUSA
- Start date
My TCS works fine now. I am still using my old ABS computer which has the 4 TCS wires and they go to the ECU. If we switch to any type of ABS pump where the ABS computer is integrated on the pump, we would need to splice the TCS, disconnect TCS all together or not hook them up and possibly have a TCS or ABS light. Its been a while, but I did hook up that RSX pump in Ravi4L's NSX with the 4 TCS wires left over and it worked, but I think a light was on (TCS or ABS). I should probably just get a spare ECU and hook up the 4 wires and pray it works. It worked as in the pump engages and the pedal vibrates etc. The light is clearly on because the TCS cannot see the wheel speed sensors. This brings up another interesting point that each speed sensor has 2 wires. 4 wheels x 2 wires(1 signal and 1 ground) = 8 wires. I have this at the pump, but the TCS has to know what the wheels are doing (ie. wheel speed sensors). The remaining 4 wires MUST be the signal from each wheel. I was going to run those into the signal wire from each wheel as there are 4 of them, but I got scared and thought..."What if I am incorrect?" :redface:
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Sounds technical. I was asking though for myself with tcs since mine is never on because of my Aem ems.
But sounds to me like it's a nice upgrade of you do not need tcs and want a newer style unit?
But sounds to me like it's a nice upgrade of you do not need tcs and want a newer style unit?
In that case its a no brainer! TCS derived from the EMS is far superior than the 91 TCS anyway. I can build you one if you want, but we really need to try those wilwood valves first for safety.
It's my understanding TCS on the AEM is just TCS. TCS on the OEM ECU is actually stability control.
TCS = Traction control for straight line traction
Stability Control = Prevents spin outs etc...
I don't have an AEM EMS so I never had a chance to verify this.
TCS = Traction control for straight line traction
Stability Control = Prevents spin outs etc...
I don't have an AEM EMS so I never had a chance to verify this.
I've had my ABS by-passed for as long as I have had my car (it was my first "mod" to the car right after buying it). I always talk about getting the solenoids cleaned out and the ABS back to working condition, but unfortunately haven't gotten around to it.
I know it's a safety issue and I have locked up the brakes on the rare occasion (w/ tires that need to be replaced), but I think since I know that it is disabled I take that into account when driving and leave space/brake accordingly (granted that's not always going to save me).
Since I've had it disabled for so long, it's been tempting to remove the system to save some weight, but haven't done it yet on the off chance I finally get around to fixing it.
Also, none of my previous cars have ever had ABS, so I'm sort of used to driving with the knowledge of possibly locking up the wheels if I brake too hard.
http://www.nsxprime.com/wiki/Abs
To bypass a non-functioning ABS system without throwing codes or warning lights is to simply short the pressure sensor connector (57390-SM4-003 001 SWITCH ASSY., PRESSURE) will cause the ABS system to show OK. The pressure sensor connector is the orange one underneath brake master cylinder, separate and use a jumper wire to short the connection that comes from the bulkhead. Pulling fuses, relays from the ABS will throw warning lights and also cause the TCS not to function.
I know it's a safety issue and I have locked up the brakes on the rare occasion (w/ tires that need to be replaced), but I think since I know that it is disabled I take that into account when driving and leave space/brake accordingly (granted that's not always going to save me).
Since I've had it disabled for so long, it's been tempting to remove the system to save some weight, but haven't done it yet on the off chance I finally get around to fixing it.
Also, none of my previous cars have ever had ABS, so I'm sort of used to driving with the knowledge of possibly locking up the wheels if I brake too hard.
http://www.nsxprime.com/wiki/Abs
To bypass a non-functioning ABS system without throwing codes or warning lights is to simply short the pressure sensor connector (57390-SM4-003 001 SWITCH ASSY., PRESSURE) will cause the ABS system to show OK. The pressure sensor connector is the orange one underneath brake master cylinder, separate and use a jumper wire to short the connection that comes from the bulkhead. Pulling fuses, relays from the ABS will throw warning lights and also cause the TCS not to function.
^^ Thanks for that! I need to read that in detail. Logically in my head if the pressure sensor harness is shorted then the system will assume the system is pressurized and "still working". Then what if the wheel sensors trigger the ABS to come on? What happens then since no fuses have been removed and essentially the system is still active?
It's easy enough to bypass the harness so I will give this a try soon.
It's easy enough to bypass the harness so I will give this a try soon.
I have the pressure switch shorted as well and my ABS still engages. I think it just lets the old ABS computer know that the nitrogen ball is charged.
I have some questions for those who know braking and ABS better than I.
If an owner puts wider tires on their car, particularly on the rears, this changes the shape of the contact patch to wider (side to side) and narrower ( front to back)
In theory this increases grip for lateral forces (cornering) and reduces grip for front to back forces (accelerating and braking).
In addition with the rear tires seeing the greatest increase in width this should result in a greater loss in rear wheel braking
The end result should result in earlier lock-ups and so the ABS system should come on more under braking.
If the owner then adds a BBK increasing brake torque on the reduced grip tire configuration then lock-ups should come even earlier and further increase ABS use.
If this is correct then the wider tire/BBK set-up should be more prone to locking up (rears first) and would see more benefit to ABS than no ABS
Under hard use (track) or low traction (rain) the lower braking grip should see the ABS come on more often.
If this is true then the wider the tires plus a BBK needs a faster/better ABS system for safe driving.
The original system was never designed to cope with this change in forces.
When Honda increased the NSX tire size and raised horsepower, I wonder if they improved the ABS system to compensate for more hp and reduced braking grip?
Would appreciate hearing from the experts on this.
If an owner puts wider tires on their car, particularly on the rears, this changes the shape of the contact patch to wider (side to side) and narrower ( front to back)
In theory this increases grip for lateral forces (cornering) and reduces grip for front to back forces (accelerating and braking).
In addition with the rear tires seeing the greatest increase in width this should result in a greater loss in rear wheel braking
The end result should result in earlier lock-ups and so the ABS system should come on more under braking.
If the owner then adds a BBK increasing brake torque on the reduced grip tire configuration then lock-ups should come even earlier and further increase ABS use.
If this is correct then the wider tire/BBK set-up should be more prone to locking up (rears first) and would see more benefit to ABS than no ABS
Under hard use (track) or low traction (rain) the lower braking grip should see the ABS come on more often.
If this is true then the wider the tires plus a BBK needs a faster/better ABS system for safe driving.
The original system was never designed to cope with this change in forces.
When Honda increased the NSX tire size and raised horsepower, I wonder if they improved the ABS system to compensate for more hp and reduced braking grip?
Would appreciate hearing from the experts on this.
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I've never heard anyone claim that wider tires reduces the ability to accelerate or brake. I thought those abilities primarily depend on the size of the contact patch, not its shape, and the size is unchanged.
Also, the benefit of wider tires on cornering isn't all that substantial - certainly not compared with other factors, like getting a make/model of tire that is significantly stickier.
I doubt that the changes in stock tire size over the years made any noticeable difference in braking ability, or brake bias. And certainly not as much as the changes in the brakes themselves (calipers, ABS, etc).
Also, the benefit of wider tires on cornering isn't all that substantial - certainly not compared with other factors, like getting a make/model of tire that is significantly stickier.
I doubt that the changes in stock tire size over the years made any noticeable difference in braking ability, or brake bias. And certainly not as much as the changes in the brakes themselves (calipers, ABS, etc).
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Let's say we have two tires each with a 16 sq. in. contact patch, one is 4 " wide so has a 4" x 4" contact patch and the other is 8" wide with a 2" x 8" contact patch.
Is your point (ignoring the rubber compound) that because the contact patch is a same area they both have the same lateral and for/aft grip?
I can understand that but then what's the benefit of wide tires?
Wouldn't wider tires provide a greater contact area thus improving all around performance if compounds were not taken into consideration? The reason I ask is because if it does not change the contact area then why do people who track their cars put really wide tires on?
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My understanding is the tire patch is determined by dividing vehicle weight by the psi of the tire divided by four to get each wheel's patch.
So a 3000 lb. car with tire pressure of 30 psi has 100 sq. in. of tire patch or about 25 sq. in. per tire.
The tire width doesn't change the contact patch area, it only changes the shape of the patch.
A wider tire has a narrower front to back distance and a narrower tire has a larger front to back distance.
From my reading, wide tire patch shapes are more oval than square.
A number of internet sources say a wider tire has more lateral grip because as the tire corners and starts to slip there is a longer side to side tire patch to help keep the grip.
Another source said that a wider tire will hydroplane quicker because the front to back patch size is narrow and the water can float the tire easier.
This is where I concluded what you gain in cornering with a wide tire you lose in fore/aft grip.
I've learned that Porsche has spent a lot of time in this area on the 911 to use the right tire sizes to help deal with the oversteer that comes from mass of the engine being behind the rear wheels.
If we could get an owner with racing experience perhaps they can explain this?
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That's correct.
This is a pretty good article about all of this, and the advantages of wider tires in cornering (which, as noted above, are still relatively minor):
Tyres, Grip, and All That...
That's a good article and I've learned I was incorrect in my assumption of lateral and fore/aft tire grip.
The main benefit of a wider tire is generating less heat.
I didn't know that.
Thanks for the link
Afaik, Honda did not change the ABS when the larger tires were introduced but they did in 1997 with the NA2 model.
Even if the 1997+ still uses the older ABS-accumulator, the pulse rate is much quicker than that on the 1991-1996 ABS-system.
So, in essence, the NSX has had three different setups of which the 2002+ is of course the superior model but alas also the most expensive
There was a slight change in the modulator in 1993, but the rest of the system remained the same.
I was researching deleting the ABS, as I've had my fuse pulled for most of the time I've owned the car.
Just wanted to point those looking to delete the ABS to this really wonderful thread: http://www.nsxprime.com/forum/showthread.php/165637-ABS-delete
Mac Attack has some detailed photos of his beautiful ABS delete which I will end up replicating in the future.
Just wanted to point those looking to delete the ABS to this really wonderful thread: http://www.nsxprime.com/forum/showthread.php/165637-ABS-delete
Mac Attack has some detailed photos of his beautiful ABS delete which I will end up replicating in the future.
I would love to buy that setup.
I was researching deleting the ABS, as I've had my fuse pulled for most of the time I've owned the car.
Just wanted to point those looking to delete the ABS to this really wonderful thread: http://www.nsxprime.com/forum/showthread.php/165637-ABS-delete
Mac Attack has some detailed photos of his beautiful ABS delete which I will end up replicating in the future.
That is pretty much the same setup I have, I got mine from Dali (good luck getting it now) 2 yrs ago and I was able to remove a ton of wiring and that heavy abs monstrosity. It makes the under hood look very clean, I went to the auto parts store got brake lines to the lengths I needed that already had the the fittings on them with flared ends and bent them to shape. I have stop techs on all four corners and to tell you the truth I personally felt the car stopped better with more pressure going to the rear brakes than stock bias. I have never owned a car with abs so I just took my unit out of my 92 because it was leaking.
I was researching deleting the ABS, as I've had my fuse pulled for most of the time I've owned the car.
Just wanted to point those looking to delete the ABS to this really wonderful thread: http://www.nsxprime.com/forum/showthread.php/165637-ABS-delete
Mac Attack has some detailed photos of his beautiful ABS delete which I will end up replicating in the future.
I'd be interested in buying that as well.
Thanks for the positive feedback everyone.
Besides the distribution blocks which I had leftover from Dali's kit, I listed all of the parts I bought and used in one of those threads :wink: You can buy those distribution blocks separately too, but Dali's price for those, the fittings, and the flexible line you can use off of the brake MC's are worth it buying from him.
The tubing is weak enough to bend by hand. Just don't bend it multiple times (since you weaken it), and don't exceed the minimum bend radius that is typically specified by the tube manufacturer. Otherwise, you'll just need to buy a flare tool and practice making flares. It's really not that difficult.
The hard part is piecing together the components and fittings. Those little suckers add up.
Dave
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Just want to add that I like what syndicate has done. I'd like to test it out and am curious on what a kit price would be.
Dave
Besides the distribution blocks which I had leftover from Dali's kit, I listed all of the parts I bought and used in one of those threads :wink: You can buy those distribution blocks separately too, but Dali's price for those, the fittings, and the flexible line you can use off of the brake MC's are worth it buying from him.
The tubing is weak enough to bend by hand. Just don't bend it multiple times (since you weaken it), and don't exceed the minimum bend radius that is typically specified by the tube manufacturer. Otherwise, you'll just need to buy a flare tool and practice making flares. It's really not that difficult.
The hard part is piecing together the components and fittings. Those little suckers add up.
Dave
- - - Updated - - -
Just want to add that I like what syndicate has done. I'd like to test it out and am curious on what a kit price would be.
Dave
