ABS retrofitting into EA car

[s'ko]

alrighty.... so I had a really close encounter on the way to work today where I was stopping and my brakes locked up and I almost tagged the car in front of me. Aside from keeping more distance between me and the car in front of me, I would like to avoid the whole wheels locking up event in the future.

 

How hard is it to retrofit ABS into an EA car? I realize that the rears might be a challenge b/c there is no way to bolt in EJ stuff. Since we are already talking custom application, it may not even have to be an ABS unit from a subaru.

 

My understanding of how ABS works is that there are sensors on the wheels and it tells the computer if a wheel is locked up. The vehicle speed sensor tells that computer that the car is moving and it pulses the brakes so that the wheel does not lock up.

 

thoughts?

 

BW

[Phizinza]

I'd be a bit nervous of retro fitted ABS. My brothers old Mazda (89 model I think) had it but it failed a locked up just one wheel with no pressure to the others almost crashed it into a tree. Ended up unplugging it and bleeding all the brakes. No problems after that.

[bheinen74]

Nearly impossible retro fit project, and will probably never function properly. Not worth the money, time, effort.

besides, if your normal brakes are in proper repair, they should stop shorter than ABS.

[bobjr94]

Im sure it could be done but may take more time than its worth. It would be hard to make something work in the rear. You would need identical size and tooth count rotor for the sensor to read, or it would think the wheel speed is different front & back and disable the system. I also dont know if it would work as a standalone unit(with out input from the engine computer).

[kingbobdole]

IIRC the tone ring is simply pressed on to the outer end of the CVs. That shouldn't be a problem really, but mounting the sensors and the modulator and wiring the whole thing is just a waste. ABS sucks and really is only intended for panic stopping, not winter use or anytime traction is really the problem. Just learn to keep your distance and pump your own brakes if need be, it works better, is cheaper and less problematic.

[carfreak85]

Put on the stickiest tires you can find. You will not be able to lock them up again with the tiny EA brakes.

[nipper]

Much better to just upgrade the brake comonenets and drive defensivly. Even if it was possible to upgrade, not guarentte that it would improve braking.

 

nipper

[boxerbob]

i recommend stickier tires too. or wider with plenty of tread. ABS is really bad in winter too. really it does suck all around.

[idosubaru]

i agree, not a good idea and not the way to go about improving your braking. start by changing your fluid and getting better brake pads. the next upgrade would be larger brakes. tires...and of course driving style and getting that engine out of your trunk, etc.

 

ABS sucks in the snow too...so you'll be left with maybe an improvement in an emergency condition but a guaranteed detrimental affect in the winter.

 

that's a lot of work for all of that. not too mention the cheaper solution is to just buy a legacy or impreza, they can be had very cheap now and you get 5 lug, better motor, air bags, etc. buying one would be far cheaper than piecing together an ABS set up.

 

the easiest retrofit option would be one from an EA vehicle. but that's also your worst option, older ABS systems are not that great. Subaru did have ABS in some XT6 markets overseas, don't know about EA's but none in the US.

 

IIRC the tone ring is simply pressed on to the outer end of the CVs.

on 2000+ Subaru's it's pressed onto the CV. on pre-2000 subaru's it's on the hub.

[Numbchux]

most early ABS systems are so focused on allowing you to turn, that they drastically sacrifice straight-line stopping. only newer (STi and '06+ for subarus) systems take into account steering angle, weight transfer, etc. to be truly effective. These sensors would be even harder to make work right, and without them, the system is useless.

 

for example, this winter, about an inch of snow on the ground. I had to borrow my girlfriend's '96 Outback for work. the ABS was pissing me off, so I did a little test. little un-tracked stretch of road, see how fast the car stopped from 15mph with ABS, then I un-plugged one of the wheel sensors (disabling the system), and tried it again. making no effort to keep the wheels spinning, just locking them up, and stopped in a fraction of the distance.

 

 

 

All that being said. if you're going 5-lug, I think it would be possible to retrofit the crappy old ABS system into them. use EJ front stuff, easy. and take a look at the XT6 rears. I'm pretty sure the XT6s were intended to have ABS at some point, or in some market. the 5 extra holes in the hub are almost exactly the same as how the front tone rings are attached to 1st gen legacy hubs. and there's a set of holes in the backing plate that would be perfect for a sensor. both visible in this picture:

[the_postie]

Here's a link to a couple of pics with ej abs on ea rear

http://www.ausubaru.com/forum/showpost.php?p=31508&postcount=54

[3eyedwagon]

Why, in the sweet name of jeebus, would anyone willingly put the scourge known as ABS on a vehicle? It's something that was sold to the world under false premises, now everyone thinks they need it.

 

If everyone took the time to play around a bit, go out, and learn to really drive; they would quickly realize how incredibly worthless it actually is.

 

I once measured the stopping distance of my 1995 S-10 with ABS equipped versus my 1964 Chevrolet Impala (4 huge drums of glory).

 

On dry pavement, the Impala stopped something like 12 feet sooner from 60mph. That was consistently.

On the WSP skid pad, with an inch of water on pavement, the Impala STILL out broke the S-10 by a consistent 10 foot'ish from 40mph.

I then tried the S-10 with the ABS dissabled, and it promptly handed the Impala its' @**.

 

I really think you should just go out to some deserted roads, and practice some extremely aggressive panic stops. You will be FAR better off.

 

If nothing else, look at it this way:

 

ABS is a mechanism, and what is one thing that is true of ALL mechanisms?

 

At some point, IT WILL FAIL

[baccaruda]

that looks like an awesome project.

 

Here's a link to a couple of pics with ej abs on ea rear

http://www.ausubaru.com/forum/showpost.php?p=31508&postcount=54

[NorthWet]

Why, in the sweet name of jeebus, would anyone willingly put the scourge known as ABS on a vehicle?...

First and formeost, the OP did not ask us if we liked ABS. Personal antecdotes/rants do not advance the thread. I, too, am interested in adapting ABS hardware to an EA car, but not for the reasons one might think.

 

This particular rant could be classified as rather Luddite. All technological implementations, whether real advances or not, tend to get treated this way. ABS, fuel injection, overhead valves, hydraulic brakes, electrical systems, and electrical ignition have all been discussed as useless, overly complicated, bound to fail and/or just plain dangerous. The car itself was treated as so dangerous that many places required that a person walk in front of the car to warn of its passing.

 

ABS is not inherently bad. Its implementation, particularly in American trucks, may be very poor. I do not believe that there is a modern airliner that does not use it. I am reasonably sure that many race cars use it.

 

The biggest drawback in the past has been the lack of computer processing power to properly monitor and actuate the feedback loop rapidly enough to be more effective than a skilled driver. Moore's Law will eliminate this obstacle. And most drivers are nowheres near being skilled, and almost nobody is "skilled" in a true panic situation (you really need to be a sociopath to never panic).

 

ABS will soon be as ubiquitous as hydraulic brakes (much higher failure rate than Good Ol' Mechanical Brakes!!!) and EFI.

 

My opinion, let's either help advance this thread or not comment upon it.

[idosubaru]

good points northwet. i'll add that it's no secret that older ABS systems were much worse than their modern counterparts.

[s'ko]

I am at a crossroads with this idea. Basically I was getting locked up front tires b/c I haven't driven a non-ABS car in a long time.

 

I am learning to pulse the brakes and learning to be a little more defensive. That btw has helped my mileage b/c I smash the skinny pedal less.

 

I was thinking of having my wife drive this car more often b/c it get's a lot better mileage than her SVX but we'll see about that. If she start to drive it more then I will look into the ABS retrofit, otherwise I will leave it as is.

 

BW

[NorthWet]

...

I was thinking of having my wife drive this car more often b/c it get's a lot better mileage than her SVX but we'll see about that. If she start to drive it more then I will look into the ABS retrofit' date=' otherwise I will leave it as is.

 

BW[/quote']

Semi-OT, but you opened the door ...

In real-world terms, how much more is it costing for her to drive the SVX instead of your ABS-target vehicle? Unless she drives a horrendous amount of miles, the difference is probably (in the PNW-vernacular) only the cost of a Latte or two. Given the difference in comfort, performance and safety between the SVX and anything that came before it, I can't see the logic in leaving it parked.

 

My wife, in some strange logic, leaves her SVX parked and drives a Mazda sedan with brick-hard seats and suspension (well the springs and shocks are hard, but the bushings are pretty shot). The Mazda can get out of its own way if it has to, but not so well with 3-4 adults in it. (Important in our semi-rural area where driveways enter into 50mph 2-lane roads.) Oh, and I should have mentioned her bad back that is aggravated by most car seats but not the SVX's. All this sacrifice to save a few bucks a week...

 

Speaking of saving, insurance rates on the SVX are about 1/3 less on the SVX, with ABS and airbags (my personal !yuck!) than on the Mazda. Math and logic are not my wife's strong points, so she drives the Mazda, hurting and grumbling down the road.

[3eyedwagon]

ABS, fuel injection, overhead valves, hydraulic brakes, electrical systems, and electrical ignition have all been discussed as useless, overly complicated, bound to fail and/or just plain dangerous.

 

I would never go as far as to compare ABS with fuel injection, or electrical ignition. Both were greeted with open arms by the performance community.

 

ABS is not inherently bad. Its implementation, particularly in American trucks, may be very poor. I do not believe that there is a modern airliner that does not use it. I am reasonably sure that many race cars use it.

 

I guess you have me there. I'll be certain to make sure every airliner I purchase from now on has ABS.

And yes, some race cars do use ABS, alot of them actually. But the systems in place on race cars are "slightly" improved over anything you will ever practically swap into an EA car.

 

ABS will soon be ubiquitous

 

Just because it is so, doesn't make it right.

 

This particular rant could be classified as rather Luddite. All technological implementations, whether real advances or not, tend to get treated this way.

My opinion, let's either help advance this thread or not comment upon it.

 

I never said I was against technology, or safer driving systems. However, I am in favor of people having a slight command of the 1.5 ton metal block they are controlling on the road next to me. I guess I could see how my encouragement for someone to take the time to actually learn things like "panic braking" could be misconstrued as luddism. But let me assure you; that isn't the case. I just generally think it a good idea for people to actually have some control over the car they are driving, no matter what braking system it has on it. Just think, some day I will be ranting over someone installing "lane maintaining sensors" on a 2009 Forrester.... you know, for safetys sake.

 

Just another opinion,

 

But like I previously said;

 

Go find some deserted pavement, and PRACTICE, PRACTICE, PRACTICE.

 

Do so in all conditions possible.

 

It may save your life, and it can even be a little bit of fun.

[NorthWet]

...

But like I previously said;

 

Go find some deserted pavement, and PRACTICE, PRACTICE, PRACTICE.

 

Do so in all conditions possible.

 

It may save your life, and it can even be a little bit of fun.

Abso-posi-lutely!!! I practice at-the-limit procedures as often as is safe and possible. Couldn't agree with you more that we should all know what we and our machines can, and can't, do.

 

But we are humans and not machines. We can never practice for the truly unexpected, and, as "normal" humans, the truly unexpected will make us panic and act out in reflex, not reaction. (It is hard to anticipate the sheer terror of rounding a bend on an icy road and see a full grown elk run out in front of you.) Add variables of tiredness or inattentiveness or altered state... At times like these, our mid-brain will override anything that we do with our cerebral cortex.

 

BTW, the ABS on our SVX actually seems to do a good job of staying the heck out of my way. The only time I have felt it jump in (other than while practicing practicing practicing ) was when I was going down hill on sheet ice on our gravel road. Seemed to permit a whole lot of differential-slip before activating.

[Numbchux]

I never said ABS in general is a bad idea. ever driven an STi? mmmmmm.......that system works VERY well.

 

but the early systems (I'm not sure about the SVX....that might have gotten a nicer setup) do not. Straight-line stopping is hindered drastically to allow you to turn. so if traffic stops quickly in front of you, you'll still be able to turn.......great, that helps. or coming towards a stop sign with lots of cross-traffic, hit a patch of ice......."great, I get to choose where I'm going die in this intersection, cause stopping isn't an option!"

 

And the newer systems that do work so well, have a dozen sensors, all very specifically calibrated to be mounted in certain places, facing certain directions, and for that car. retrofitting it would be impossible.

 

 

 

Oh, I also forgot to mention, when I was driving that '96 OBW in the snow. you could put the 4EAT into 1 or 2, and do pretty well. then as soon as you touched the brakes, the ABS would kick in and tell the tranny to UPshift to 3rd or 4th. this, obviously, wouldn't be an issue with your swap, but is stupid nonetheless.