Dialing in speedometer with Hypertech Calibrator

I need someone who has updated their speedometer via the Hypertech Calibrator, who had stock 265 70 16, tires - What was the stock tire measurement that you used to dial in your speedo?
I sold my stock 265/70/16's so that is the reason I am asking... I am one of this folks who likes everything dialed in exact or as close as possible... I appreciate your help

 

I got mine to match GPS, running 285/70-17, put 265/70-17 in as the stock size. Tried the original stock size first and was off by a 2-3mph.

 

May still be slightly off. I did the same thing. Better than 5-10 mph. Try the off road size 265/70/16 the stock I believe is 17” size is 265/65/17 the 70 could be doing it.

I used a hypertech for a few changes on 265/70/16 to 285/70/17 to 285/70/17 with 4.55 then now 4.56 with 315/70/17. Each one was off slightly. More now but was close.

I suggest leaving it plugged in with the UsB and feed it under your driver side. That way you can adjust without pulling everything out. I have mine setup and never have to pull it all out just plug in and change and see how it works out.

 

I tried putting in the stock tire size and it is still off, and since you can put in the actual tire height I used the standard 30.61" for the stock tire and it is till off which with my OCD is driving me nuts lol

 

Good idea, would save a lot of time and I could just bring my laptop out and hook up

 

yah no way did I want to have to do that each time. not like it happens often but I have had to do it a few times the past couple years. made it a breeze.

 

Does this device change both the speedometer and odometer for accuracy?


edit.. a little research answered my question

Hypertech's Speedometer Calibrator can correct the speedometer and odometer for tires up to 54 inches (depending on the application), and/or non-stock rear gear ratios. It is engineered for drivers who want speedometer recalibration functions without the additional expense of other tuning features.

 

Just curious does the hype tech account for 3%+\- the speedometer could be off from the factory.

 

Maybe but I don't think so? The adjustments are either made by entering your tire sizes (old and new) or by entering in your tires heights

 

I asked cause. I wonder if it was off by 3% from the get go will it still be off after. Thus driving you crazy.

 

does it constantly have to be plugged into the OBD port?

 

It plugs into the Speedometer wires and bypasses the ODB port as I recall. Mine worked great for 1 1/2 years and now it won't do anything. It tells me its programmed but nothing changes. I have used the manual option and changed it trying to see if that would do anything. It doesn't. I have done the multiple tries with the same values as sometimes I had to resort to that to get the changes to take affect. Took the dash apart multiple times and finally gave up. I just know my 285/75/r17s are 5% off and my winter tires (265/70/r16?? OEM size) are spot on for my 2014.