Author Topic: how to get the right speed  (Read 3200 times)

Offline weebo74

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how to get the right speed
« on: April 05, 2009, 09:03:31 pm »
ok so here we go i got a 1979 k10 4x4 it has 35" tries got the truck about a month ago got the thing running right and put a new speedo cable and the truck is way off is there any way to fix this thanks for all the info

Offline VileZambonie

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Re: how to get the right speed
« Reply #1 on: April 05, 2009, 09:09:57 pm »
More info about your drivetrain needed.
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Offline Lt.Del

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Re: how to get the right speed
« Reply #2 on: April 05, 2009, 09:15:36 pm »
every large town has a shop that works on calibrations.  Any tranny shop could calibrate it for you.  it is a common thing, anytime you change ratios, tranny type, wheel/tire size etc. 


Offline bfofish

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Re: how to get the right speed
« Reply #3 on: April 05, 2009, 09:41:40 pm »
An old trick I was taught years ago, go out to the highway and time yourself between the mile markers.If it takes you 60 seconds you are going 60mph ect......
Then you at least have an idea how far off your speedo is.
I know my Blazer is off by 10 at 55mph with a 4" lift and 35" tires.
Your best bet is a tranny shop or 4X4 shop to get the correct speedo gear for your trans.
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Offline Irish_Alley

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Re: how to get the right speed
« Reply #4 on: April 06, 2009, 12:22:36 am »
mines off by 3 mph w 38's but i also got the digital gages and with them you turn them on and drive a mile or have another vehicle drive in front of you at a "known speed" and set it. that was pretty much the reason i was able to talk the wife into letting me get them lol
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Offline choptop

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Re: how to get the right speed
« Reply #5 on: April 06, 2009, 11:14:18 am »
I use my GPS. Just move it from truck to truck.
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