different size front rear tires affect shift points?
08-15-2008, 12:06 AM
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different size front rear tires affect shift points? have a set of drag wheels with 165 80 15 up front, 325 50 15 in rear. with this setup seems to be over shooting the shift point and hitting the rev. limiter. tonight i put on a set of 275 50 15 in rear, with the 165 80 15 front, now no issues. how to solve this? what is the cause?
08-15-2008, 06:20 AM
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Its your car telling you that there is no need for 325-50-15's.
No but really I'm not understanding your question. Your asking if the taller tire is changing your cars shift points correct? Is your car a 6-speed or an A4? Those 325's are almost 28" tall...
No but really I'm not understanding your question. Your asking if the taller tire is changing your cars shift points correct? Is your car a 6-speed or an A4? Those 325's are almost 28" tall...
08-15-2008, 07:52 AM
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The rears will, the fronts have no effect.
Taller tires read lower mph than what you're actually going. If it shows 65mph, you're actually going 70 with the 325s.
Taller tires read lower mph than what you're actually going. If it shows 65mph, you're actually going 70 with the 325s.
08-15-2008, 08:31 AM
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The stagger isn't causing the shift points to be off its the tall rear tire height that is causing a change in the spedo and throwing off the shifts. the stagger though will cause the ABS to work incorrectly and constantly think the wheels are locking up. this means in a hard stop the the ABS will kick on and keep you from stopping.
08-15-2008, 01:43 PM
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i knew the rears did change the speedo/shift points. there is a programmer in the car adjusted for tire size and gears. thought i read somewhere that the stagger tire sizes affectedthe shift points also. my bad. just that with the 325's on the back the shift points where hitting the rev. limiter. now with the 275 50's on there it is not. i have no clue.
