4.11's effect on speedo

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Feb 7, 2008 | 05:27 PM

jattgunman

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From: Cali

4.11's effect on speedo

I just got 4.11's in a new 9 inch and noticed that speedo seems to be off~5mph over..Does that sound about rite?...I tried the search but it wasnt working

Feb 7, 2008 | 05:32 PM

Calstud86

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This past December I put in 3.73's and my speedo was off by 11mph. a simple tune will adjust it. Nothing to sweat at all.

Feb 7, 2008 | 09:01 PM

jattgunman

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From: Cali

YEa its not a big deal but just really annoying..

Feb 8, 2008 | 12:30 AM

Sunset'01Z

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of course it's going to be off

your speed is measured off of the trans, so when you put lower gears in it, your driveline is turning faster to keep your car at cruise speed. a tune will fix it.

Feb 12, 2008 | 06:00 PM

ss1

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My car has 4.11's but the computer still thinks it has 3.73's. It's off 10-11mph as well.

Feb 12, 2008 | 06:03 PM

SS1875

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Quote:

Originally Posted by jattgunman

I just got 4.11's in a new 9 inch and noticed that speedo seems to be off~5mph over..Does that sound about rite?...I tried the search but it wasnt working

I had 4.11's in my 12 bolt...5-7 MPH was what I noticed on mine. Tuning eliminated it though.