changing tire size and ECU/abs problem

lgirard · 12-08-2016, 10:25 PM

Quote:

Originally Posted by BGTV8

Dude, check your maths ....... 265/35R19 is ~ 668mm in diameter and 285/35R19 is ~ 682 mm in diameter.

Difference is outside tolerance (just) and is enough to upset the ABS calibration.

The ABS brake controller is monitoring the number of rotations front and rear to detect a locked (or about to lock) wheel and because ofn the sizes, it is getting confused as it will not tolerate more than ~3% difference in diameter and rotation speed. This is NOT in the ECU, it is in the ABS controller.

I run 265/35R18 front and back on 10" wide rims for track duty - for DD use I have a set of 245/45R18 and 275/40R18.

Your tyre size choice is the problem and a fix in the ABS controller is probably beyond anyone other that the ABS system OEM.

That I understand ... I originally started with that setup I it became clear to me that the problem was with diameter diference. where I am confused though, is when I brought back my 245-40-19 while keeping my 285-35-19. Diameter difference is now within 1%. and I am still experiencing ABS over reaction. is there some other criterias like rear tires diameter must be lower or equal than front tires !

thanks for you help

Rusty · 12-08-2016, 10:44 PM

The issues you are having is not tire diameter, but VDC. With it off. It still will affect the car. To help out. You have to disable the yaw sensor.

DIY Yaw Sensor rocker switch

lgirard · 12-10-2016, 06:04 AM

Quote:

Originally Posted by Rusty

The issues you are having is not tire diameter, but VDC. With it off. It still will affect the car. To help out. You have to disable the yaw sensor.

DIY Yaw Sensor rocker switch

What effect on the car behavior will disabling the yaw sendor do ?

12-08-2016, 10:44 PM	#2 (permalink)
Rusty A True Z Fanatic Join Date: Dec 2011 Location: Fayettenam,Pennsyltucky Age: 70 Posts: 35,571 Drives: 2011 Nismo GM 6M Rep Power: 2684440	The issues you are having is not tire diameter, but VDC. With it off. It still will affect the car. To help out. You have to disable the yaw sensor. DIY Yaw Sensor rocker switch __________________ 浪人 - 殺し屋 "The Difficult Anytime, The Impossible By Appointment Only" http://www.the370z.com/members-370z-...o-journal.html

Similar Threads
Thread	Thread Starter	Forum	Replies	Last Post
Widest tire size to put on base 18" rims with spacers ? What size?	Mynamedoublem	Wheels & Tires	16	06-23-2021 01:10 PM
Anyone dropped nd with this tire size having problem??	Rafiton	Wheels & Tires	1	11-21-2014 01:13 PM
Changing tire size on same Venaci Rim	seahorse12	Wheels & Tires	6	01-28-2014 02:08 PM
changing tire profile size dangerous?	MD-370z	Wheels & Tires	22	09-07-2011 08:20 PM
Tire size	laricb	Wheels & Tires	3	03-06-2011 06:33 PM