MPH Difference with Gear Swap

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Sep 10, 2012 | 11:36 PM

cammed00

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From: Ft.Worth

MPH Difference with Gear Swap

Went from 275/55/20 to 255/65/17 and from 3.42 to 4.10 so question is,what would the mph difference with those 2 thing and I can't get a re-tune until October.

Thanks fellas

Sep 10, 2012 | 11:43 PM

Preston129

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Approx 500RPM higher at ~60mph in 4th with the new setup versus old.

Edit, sorry, noticed I responded with RPM difference rather than MPH one.

Last edited by Preston129; Sep 11, 2012 at 11:43 AM.

Sep 11, 2012 | 10:02 AM

Beau@SDPC

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Sep 11, 2012 | 10:25 AM

nonnieselman

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From: Crystal Springs, MS

275/55/20 3.42 75mph =1900rpms 2000rpms = 79mph

255/65/17 4.10 75mph = 2400rpms 2000rpms = 62mph

Sep 11, 2012 | 11:39 AM

Mud slinger

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Do you have an iPhone, or smart phone? I have an app called speed-o-meter that tells you your speed by gps. Comes in handy sometimes.

Sep 11, 2012 | 12:10 PM

Beau@SDPC

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From: Lubbock, TX

I use ^ that ^ also. Came in pretty handy after the gear swap, even with a retune.

Sep 11, 2012 | 12:11 PM

cammed00

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From: Ft.Worth

Thanks fellas!!
Mud Slinger yes I do have an iPhone and I'll check that app out cuz black bear won't be back here till October.

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