ABS Coding when upgrading to R32 Fronts

[Peej]

Hey all,

Just fitted an R32 setup to my 'Rocco GT - someone has mentioned that I may need to 'adjust the ABS coding' to suit the larger brakes - any know more about this or is it not something i need to worry about?

Thanks!

P.

[Statller-Stevo]

No

[Andy]

didn't when i put them on my tdi

[Peej]

Perfect - thanks for the quick response!! :):)

P.

[RedRobin]

.
No coding done or mentioned when AP Racing's chief engineer fitted my front brakes up at Coventry and they know more than just a thing or two about brakes.

Also, if Statller also say no (as posted above) then that's another confirmation by someone who is very knowledgable. Unless we are all wrong!

And A Warm Welcome to the forum, Peej  

[RedRobin]

.
Just a further thought: As i understand it, the sensors which the ABS coding use only feed information/react according to the physics of your car's behaviour. That behaviour/movement being directly in response to the road/track/driving conditions and the way in which you are driving.

In turn, the application of the brakes further influences the ABS system, and on it goes. That very tactile balance of braking, suspension, and handling is something I particularly enjoy experiencing when driving. State of your tyres too and lack of grip, will influence ABS. Also, chassis stiffness (UNIbraces, roll-cage).

In the same way, extra coding isn't necessary when a LSD is installed, or aftermarket suspension modifications.

No coding either when my S3/R32 rear brakes were fitted.

If I am wrong about any of this, someone please correct me, but so far I haven't found myself propelled into a ditch and the ESP/ABS doesn't constantly kick in when making progress  

[E30Dom]

Plus I think the ABS sensor is taken off the hub, and is not intelligent to know if you have bigger brakes... It will just cut the brake force if they detect lock..

[RedRobin]

Plus I think the ABS sensor is taken off the hub, and is not intelligent to know if you have bigger brakes... It will just cut the brake force if they detect lock..

....Good point   I wonder if any coding should be done when a GTI's hubs are changed to TT's, as some folks have done.

[E30Dom]

Probably not, I think the sensor just looks in a stop in digital signal, it's either on or off as the proximity sensor picks up the notch on the hub, and works the abs accordingly..

[Statller-Stevo]

Plus I think the ABS sensor is taken off the hub, and is not intelligent to know if you have bigger brakes... It will just cut the brake force if they detect lock..

....Good point   I wonder if any coding should be done when a GTI's hubs are changed to TT's, as some folks have done.

No 

[DaveB@Vagbremtechnic]

Had this old chestnut on the Mk4s it's actually coded to wheel size not brake size.

In the good old days of the Mk4 the R32 was the only car that got 18s before the anni came along.

So when the inevitable big debate came along with the vagcom warriors who wanted to adjust EVERYTHING, we had to wait for somebody to scan the anni to see how it was factory coded. It was coded to 18s and not 312 brakes that the anni got.

I would suggest that it's probably more to do with grippy tyres and generally 18s being gripper than the firestone tat they used to put on the OEM 17" Santa Monica's which was the biggest orderable alloy prior to the ANni coming along.

The tyre quality arguement makes more sense than "brake power" to hopefully make sure the ABS doesn't intervene too early and extend braking distance

[RedRobin]

Had this old chestnut on the Mk4s it's actually coded to wheel size not brake size.

....So am I right in understanding that if your car (Mk5 GTI) left the factory with Monza 17's and you later changed them to 18's, and you didn't do any VCDS coding revisions, then your ABS would be working 'inaccurately'?

[Hedge]

If it is coded on the Mk5 I would have thought it would be done on circumference or diameter rather than 17" or 18".

[RedRobin]

If it is coded on the Mk5 I would have thought it would be done on circumference or diameter rather than 17" or 18".

....Sure, but I was only using the 17" and 18" terms to identify the wheels. Most of us don't know the circumferences of our wheels.

Hang on, the 17" and 18" measurements are diameters. I'm now more confused than usual. What do you mean by your post's wording, Ian?

[Hedge]

Well the circumference of the wheel and tyre for 17" and 18" is the same (or should be) so no change. 

Simples!