The ABS discussion thread

sharathjeppu · 31st January 2007, 10:21

Here's a video that gives an idea of how ABS, TCS and ESP works. It's quite interesting. Since it's a fairly long video, would recommend downloading and watching it using the Google Video Player.

Fifth_Gear_- slk55_vs_sl55

rks · 31st January 2007, 16:48

There is a point about ABS that needs to be clearly understood. If you brake *hard*, the ABS kicks in to prevent a lock-up of the wheels by pumping the brakes automatically via computer control. The point is that in a long emergency braking effort, you should apply maximum pressure straightaway and then hold that pressure. This will ensure that the ABS kicks in at the beginning of your braking effort and minimize the braking distance. If you do not apply full braking pressure immediately and then increase the pressure at a later point of time, that is when the ABS will kick in and your braking distance could possibly increase because the computers will not have enough time to pump the brakes optimally (maybe better to have a lock-up of the wheels at the end of the braking effort rather than to have the ABS kick in at that point, with not much distance left to avert a collision).

So, to summarize, with ABS present, if at all it kicks in, it should do so towards the beginning of the braking effort, with some distance left to stop. Otherwise the ABS should not kick in at all. Hence using the ABS correctly needs some practice, especially for old-timers who are already used to reacting in their own ways towards emergencies. I imagine it would be quite difficult to change these long-cultivated reflex reactions.

The problem, as I had mentioned in another thread, is that with ABS present and kicking in, it is more difficult to adjust your braking effort to utilze the full braking distance available - the computers only try to minimize the braking distance and not optimize it (say, in order to prevent rear-ending and to increase brake life).

higautham · 27th February 2007, 23:15

does the ABS get affected when v change or upsize the wheels or tyre.

can ABS be fitted in with drum breaks also. does the SWIFT VDI ABS have a four wheel ABS.

paras211 · 28th February 2007, 05:15

i wish i had abs on me old corolla i banged into the back of a taxi
me unharmed me car took 1 month to recover
how much would it cost to put abs in my corolla since the new corolla has it so it can be installed right??

srishiva · 28th February 2007, 11:59

ABS is not used to minimize the braking distance. It is used to prevent wheel lockup and hence give you the ability to steer away. I don't think there is any adjustment a 'expert' driver needs to do.(I have never heard any complaining against cars like porshe, ferrari etc., saying "Damn ABS") The natural reflex action during a imminent accident is to steer away and not to stop before that. Its used to avoid hitting someone.

mithun · 3rd March 2007, 07:26

Quote:

Originally Posted by higautham

does the ABS get affected when v change or upsize the wheels or tyre.

There will not be any problem with the whole ABS system even if you change tyres/rims/alloys since it's mounted on the vehicle's axle.

sharathjeppu · 3rd March 2007, 07:46

Will ABS performance be affected by a change in tire size during replacement?

Use of tires other than original equipment specification is not recommended. Optimum performance of ABS is obtained when tyre size matches with OEM specified one.

Source : Sundaram Clayton Limited-ABS

mithun · 7th March 2007, 06:26

I don't know which of the info is true since it's been notified to me by a Maruti engineer(working at it's factory) that the whole ABS system is mounted on the vehicle's axle so changing tyres/rims/alloys has no effect on it.

mithun · 7th March 2007, 06:28

Quote:

Originally Posted by sharathjeppu

Will ABS performance be affected by a change in tire size during replacement?

Use of tires other than original equipment specification is not recommended. Optimum performance of ABS is obtained when tyre size matches with OEM specified one.

Source : Sundaram Clayton Limited-ABS

I don't know which of the info is true since it's been notified to me by a Maruti engineer(working at it's factory) that the whole ABS system is mounted on the vehicle's axle so changing tyres/rims/alloys has no effect on it.

vikram_d · 7th March 2007, 06:39

I have upsized tyres on my swift and have found that the abs works just fine with them.

devilvtec · 9th March 2007, 11:09

Quote:

Originally Posted by jigarmuni

ABS is Anti lock braking system. It is the most useful thing to have in a car...what it does is.....prevents ur wheels from locking up when u brake abruptly or suddenly with a lot of pressure..! WHat happens here is .... when u are driving a car without ABS and u lock ur wheels.... u will be loosing almost 50% of ur braking efficency, and locking up is primarily the reason for accidents..! What ABS does to ur car is.... if u happen to slam ur brakes... the ABS system on ur car will reduce the excess amount of pressure on the brakes and prevent them from locking..! Hence giving u maximum braking efficency at all times... even in the wet..!

And welll dude... even i am trying to find out ... if i can get ABS for my Honda Vtec!!

(anyone who can help me also with this ?)

even i need help .. abs for my ohc vtec ....... i know its a long and difficult task but just wonted to know how can it be done ......???

pawan · 9th March 2007, 11:53

is abs as good as claimed and efficient then what about the recent veyron crash it also has abs

Quote:

The supercar then spun three times before crashing into trees on a roadside bank before coming to rest.

this goes to prove abs wont help you to stop all the time and the pics show there is no sort of dusty surrounding as told by gto that dust affects abs braking so dust is out of the question and was traveling at 100 mph when the car is designed to handle up to 253mph.

xbox360 · 26th June 2007, 18:14

Correct me if i am wrong, but does ABS not exploit the basics physics principle that the coefficient of static friction is greater than the coefficient of kinetic friction?

xbox360 · 26th June 2007, 18:34

Quote:

Originally Posted by sharathjeppu

Here's a video that gives an idea of how ABS, TCS and ESP works. It's quite interesting. Since it's a fairly long video, would recommend downloading and watching it using the Google Video Player.

Fifth_Gear_- slk55_vs_sl55

Extremely educational video.
For the guys watching this video, the technical part is after ~12 minutes into the video.

Nitin · 27th June 2007, 00:14

I have personally experienced the boon of having ABS onboard. Even in wet conditions, tires with decent tread & winding roads, ABS helps a lot in being able to stop right where you want to. The car doesn't swerve or skid, and that helps judge where you want to move,in order to avoid hitting a vehicle in front.

The maniac drivers in Houston are notorious when it comes to lane changing- no indicators, sudden shifts 1-3 lanes across the freeway..

I'm pretty sure that the size of the tire would have some effect on the working of ABS,since the effort required to stop a vehicle with big wheels, is definitely more than a car with smaller wheels... I may be wrong though..

31st January 2007, 10:21	#46
sharathjeppu BHPian Join Date: Apr 2006 Location: Bangalore Posts: 159 Thanked: 4 Times	ABS, TCS and ESP demonstrated Here's a video that gives an idea of how ABS, TCS and ESP works. It's quite interesting. Since it's a fairly long video, would recommend downloading and watching it using the Google Video Player. Fifth_Gear_- slk55_vs_sl55
	() Thanks

31st January 2007, 16:48	#47
rks BANNED Join Date: Nov 2005 Location: ?? Posts: 1,238 Thanked: 18 Times	There is a point about ABS that needs to be clearly understood. If you brake hard, the ABS kicks in to prevent a lock-up of the wheels by pumping the brakes automatically via computer control. The point is that in a long emergency braking effort, you should apply maximum pressure straightaway and then hold that pressure. This will ensure that the ABS kicks in at the beginning of your braking effort and minimize the braking distance. If you do not apply full braking pressure immediately and then increase the pressure at a later point of time, that is when the ABS will kick in and your braking distance could possibly increase because the computers will not have enough time to pump the brakes optimally (maybe better to have a lock-up of the wheels at the end of the braking effort rather than to have the ABS kick in at that point, with not much distance left to avert a collision). So, to summarize, with ABS present, if at all it kicks in, it should do so towards the beginning of the braking effort, with some distance left to stop. Otherwise the ABS should not kick in at all. Hence using the ABS correctly needs some practice, especially for old-timers who are already used to reacting in their own ways towards emergencies. I imagine it would be quite difficult to change these long-cultivated reflex reactions. The problem, as I had mentioned in another thread, is that with ABS present and kicking in, it is more difficult to adjust your braking effort to utilze the full braking distance available - the computers only try to minimize the braking distance and not optimize it (say, in order to prevent rear-ending and to increase brake life).
	() Thanks

27th February 2007, 23:15	#48
higautham BHPian Join Date: Oct 2006 Location: Trivandrum Posts: 95 Thanked: Once	does the ABS get affected when v change or upsize the wheels or tyre. can ABS be fitted in with drum breaks also. does the SWIFT VDI ABS have a four wheel ABS.
	() Thanks

28th February 2007, 05:15	#49
paras211 BHPian Join Date: Nov 2006 Location: mumbai Posts: 647 Thanked: 114 Times View My Garage	i wish i had abs on me old corolla i banged into the back of a taxi me unharmed me car took 1 month to recover how much would it cost to put abs in my corolla since the new corolla has it so it can be installed right??
	() Thanks

28th February 2007, 11:59	#50
srishiva Senior - BHPian Join Date: Nov 2006 Location: Bengaluru Posts: 4,375 Thanked: 2,256 Times	ABS is not used to minimize the braking distance. It is used to prevent wheel lockup and hence give you the ability to steer away. I don't think there is any adjustment a 'expert' driver needs to do.(I have never heard any complaining against cars like porshe, ferrari etc., saying "Damn ABS") The natural reflex action during a imminent accident is to steer away and not to stop before that. Its used to avoid hitting someone.
	() Thanks

3rd March 2007, 07:46	#52
sharathjeppu BHPian Join Date: Apr 2006 Location: Bangalore Posts: 159 Thanked: 4 Times	Will ABS performance be affected by a change in tire size during replacement? Use of tires other than original equipment specification is not recommended. Optimum performance of ABS is obtained when tyre size matches with OEM specified one. Source : Sundaram Clayton Limited-ABS
	() Thanks

7th March 2007, 06:26	#53
mithun BANNED Join Date: Jan 2006 Location: Cochin Posts: 2,195 Thanked: 268 Times	I don't know which of the info is true since it's been notified to me by a Maruti engineer(working at it's factory) that the whole ABS system is mounted on the vehicle's axle so changing tyres/rims/alloys has no effect on it.
	() Thanks

7th March 2007, 06:39	#55
vikram_d Senior - BHPian Join Date: Jul 2006 Location: Bangalore Posts: 2,427 Thanked: 1,185 Times	I have upsized tyres on my swift and have found that the abs works just fine with them.
	() Thanks

26th June 2007, 18:14	#58
xbox360 BHPian Join Date: Mar 2007 Location: Hyderabad Posts: 254 Thanked: 91 Times View My Garage	Correct me if i am wrong, but does ABS not exploit the basics physics principle that the coefficient of static friction is greater than the coefficient of kinetic friction?
	() Thanks

27th June 2007, 00:14	#60
Nitin Senior - BHPian Join Date: May 2006 Location: Houston, Texas Posts: 3,294 Thanked: 20 Times View My Garage	I have personally experienced the boon of having ABS onboard. Even in wet conditions, tires with decent tread & winding roads, ABS helps a lot in being able to stop right where you want to. The car doesn't swerve or skid, and that helps judge where you want to move,in order to avoid hitting a vehicle in front. The maniac drivers in Houston are notorious when it comes to lane changing- no indicators, sudden shifts 1-3 lanes across the freeway.. I'm pretty sure that the size of the tire would have some effect on the working of ABS,since the effort required to stop a vehicle with big wheels, is definitely more than a car with smaller wheels... I may be wrong though..
	() Thanks