installed new gears, having trouble w/ speedo adjustment

[01MockMach1]

I just had some 3.73s installed on my 01 GT 5-speed. right afterwards i took my car to the ford dealer to have the speedometer calibrated but they were not able to make it accurate at all. i was wondering if i have any cheap options to correct this problem. right now my speedo says i am going way faster that i really am. i went through a speed trap sign with my speedo saying 25 and the speed trap said i was going 21... i am assuming that it is only going to be more off at high speeds. it not only concerns me that i can't tell how fast i am going but also that i will be putting way more miles on my odometer that i am really driving. if anyone knows of any relatively cheap fixes for this please help! thanks

 

[chrisconsin]

I havent had hands on experience with either, But I know Speedcal will fix that for about a $100.00, or a more expensive choice would be a diablo predator for roughly $400.00 obovisly with the price hike there are many more features with the predator.

You should be happy with 4mph off mine is 9mph off in that speed range.

 

[whyask]

mines off by 15 MPH... I have 4:10's

 

[WydOpn]

SCT Xcal, Diablo, Dallas Mustang, etc...all have the ability to correct the speedo for gear and tire size changes - just depends on what you want to pay (or how much you care for that matter) and if you have any use for the additional features they provide.

 

[mity2]

if your speedo said 25, and your going 21, thats really not THAT bad. My GT is stock gear, and my speedo might say 60, but my GPS navigation usually read about 6mph slower.

Remenber, Ford OEM gauge aren't known for their accuracy...
Infact, i think Ford OEM gauge is one of the worst. I remenber thinking when i bought 99 Couger how inaccurate their gauge was. I brip the gas, you can hear engine RPM goes up, then let go the pedal, you hear RPM goes down, then see the RPM needle starts to go up...

 

[DuRsT]

The rub is that you will log more miles on your odo than actually driven like this, potentially hurting resale value.

 

[goshia]

buy a diablo predator your going to need it anyway as your mods keep on going.