No ABS?

["Al Powell" <APOWELL@agcom.tamu.edu>]

Brendan Rudack <rudack@ucsub.Colorado.EDU> wrote:
> 
> Is it possible to disconnect the front ABS sensors so they are 
> non-functional leaving the car with ABS for the rear tires only?  I do 
> not like the ABS in my car and I haven't driven with it for a long time.  
> However I have noticed that occasionally a back tire will lock and I 
> would prefer to not flat spot my tires.  

Hi, Brendan.  This question is interesting.  Would you mind 
explaining why you don't like the ABS?  I'm sure you are aware that 
although it is not intended to stop you shorter than standard brakes 
(as many people seem to think) but it does provide increased ease of 
control - and often does stop shorter because of that  control.

Its primary advantages (in my understanding) are:

1) To prevent the front wheels from locking up under heavy braking; 
one "Big-T Truch" is: when the front tires lock up, you CAN NOT steer. 
Therefore, ABS offers you as a drive the chance to dynamite the 
brakes for maximum stopping ability while retaining full steering 
control.  This is truly a valuable circumstance!

I have been thru the (2-day, lightweight, OK?) Bondurant school and 
spent a week at the Washington State Patrol Driving Instructor's 
school, and I still can't trust my foot not to lock the brakes for a 
moment (maybe a long moment....) under high stress.  Therefore, I 
really like the ABS in my Audi!  I wish my 280ZXT had it.

2) ABS helps to compensate for situations in which some tires are on 
a different traction surface than others; example would be a side-of-
the-road stop in which you get our outside tires onto gravel, or 
hard braking during which you hit a patch of pavement with sand, 
gravel, or ice.  ABS will help keep you from getting seriously 
sideways or losing control in such situations.

Whether you use ABS or not is certainly your call.  However, I'm 
interested in your reasons.  Why don't we on the list chat about it?

As for your question, IMO, it would be taking a big chance to 
attempt to defeat *part* of a system like ABS.  I doubt it could be 
done safely and would suggest it most practical to simply turn it 
off.  NOTE: **If** you can't avoid occasionally locking up your rear 
tires, then I submit that you would benefit more from using ABS than 
leaving it off, as this indicates your braking reflexes are not 
superior to ABS. I suppose there are unusual circumstances in which 
ABS may be turned off to the driver's advantage...but none come to 
mind at the moment.

>     Also,  I would like to upgrade to the dual piston calipers on the 
> TQ.  Does anyone know if the 4-bolt 10.9 inch rotors found on the coupe 
> and 90Q20v have the same offset as my 4-bolt 10.1 inchers?  Also, are the 
> calipers on the coupe the same as those found on the 5000TQ?  One last 
> thing, should there be any clearance problems with my stock 14inch wheels 
> with the larger brakes?

Can't help you on this question.  I suspect that if you can change 
the calipers, larger diameter wheels will be required.  BUT - a 
question: what's your goal for this conversion?  Other list-members 
might be able to suggest options is they know what your *purpose* is.  
If your goal is to reduce brake fade, different pads and drilled 
rotors might be indicated...and much simpler to do.
Al Powell                           Voice:  409/845-2807
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