Fitted 265/35's on the front and found this
04-02-2017, 05:30 AM
#27
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Thread Starter
04-02-2017, 09:15 AM
#28
You know the speedo won't be affected by width change if the rolling diameter doesn't change, right? I notice you keep saying the differential change between the front and rears. The speedo is calculated by the transmission and what it is driving and that would be the rear wheels.
Last edited by shoe3k; 04-02-2017 at 09:18 AM.
04-02-2017, 10:53 AM
#29
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'15 C63S
You know the speedo won't be affected by width change if the rolling diameter doesn't change, right? I notice you keep saying the differential change between the front and rears. The speedo is calculated by the transmission and what it is driving and that would be the rear wheels.
These systems monitor individual wheel speed, and if you have a different diameter ratio front/rear than stock, the systems will think wheels are slipping differently than they really are. They will be reading a certain angular velocity and monitor how it relates to a given vehicle speed, and if the ratio is off this calculation won't be as precise as it could otherwise be. It doesn't make the car unsafe to drive, it just makes the systems less effective.
The rule of thumb has always been to keep the front/rear diameter ratio the same as stock as to not upset the systems.
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shoe3k (04-02-2017)
04-02-2017, 10:59 AM
#30
Super Member
It's not the speedometer that is at issue, it's the traction/skid/stability control that would have issues.
These systems monitor individual wheel speed, and if you have a different diameter ratio front/rear than stock, the systems will think wheels are slipping differently than they really are. They will be reading a certain angular velocity and monitor how it relates to a given vehicle speed, and if the ratio is off this calculation won't be as precise as it could otherwise be. It doesn't make the car unsafe to drive, it just makes the systems less effective.
The rule of thumb has always been to keep the front/rear diameter ratio the same as stock as to not upset the systems.
These systems monitor individual wheel speed, and if you have a different diameter ratio front/rear than stock, the systems will think wheels are slipping differently than they really are. They will be reading a certain angular velocity and monitor how it relates to a given vehicle speed, and if the ratio is off this calculation won't be as precise as it could otherwise be. It doesn't make the car unsafe to drive, it just makes the systems less effective.
The rule of thumb has always been to keep the front/rear diameter ratio the same as stock as to not upset the systems.
04-02-2017, 08:24 PM
#31
It's not the speedometer that is at issue, it's the traction/skid/stability control that would have issues.
These systems monitor individual wheel speed, and if you have a different diameter ratio front/rear than stock, the systems will think wheels are slipping differently than they really are. They will be reading a certain angular velocity and monitor how it relates to a given vehicle speed, and if the ratio is off this calculation won't be as precise as it could otherwise be. It doesn't make the car unsafe to drive, it just makes the systems less effective.
The rule of thumb has always been to keep the front/rear diameter ratio the same as stock as to not upset the systems.
These systems monitor individual wheel speed, and if you have a different diameter ratio front/rear than stock, the systems will think wheels are slipping differently than they really are. They will be reading a certain angular velocity and monitor how it relates to a given vehicle speed, and if the ratio is off this calculation won't be as precise as it could otherwise be. It doesn't make the car unsafe to drive, it just makes the systems less effective.
The rule of thumb has always been to keep the front/rear diameter ratio the same as stock as to not upset the systems.
04-03-2017, 09:36 AM
#33
Super Member
Guys, those who changed their tires to 265 f and 285 t, do you notice any difference in the accelration and throttle response? I dont know but i feel the car is less responsive when i hit thr accelerator. Something is weird, the car just feels alot heavier?
04-05-2017, 07:02 AM
#35
Super Member
