Hypertech Speedo Calibrator

Hello members! First time user here. My question concerns an inline Hypertech Speedo Calibrator and maybe some tricks or tweaks I may have missed when I insalled it in my 2016 Tacoma TRD Off Road. The stock tires were 265/70/R16 and now I am running 285/70/R17. I installed the calibrator acording to instructions and found there was almost a 5 mph differencet in actual speed and speedo diaplaym (display is slower). I checked the speedometer gps against my friends 2014 F150 and there was approx 1 mph and less difference between app reading and the F150 reading. What is going on with my Hypertech unit and what, if anything, am I doing incorrectly?

 

Try contacting Hypertech, or search here for it . There is a specific way to calibrate. I just dont recall what it was. something about just adding the true tire size and not anything about gearing. Its on here.

 

Use the actual tire sizes in inches.

 

I sent a message to Hypertech and waiting on reply. Meanwhile, I contacted a different supplier than who I purchased the unit and the rep said to play around with the diameters of the stock tires and see what happens. I did bur haven't tested it yet. Thanks for your help. I need all I can get!​

 

I did use actual tire size in inches. Nothing changed.

 

What values did you use. Are you using the diameter of the actual tires or..?

What tires do you have now.

 

I used the actual diameter of the stock tires (30.61) and the present tires: 285/70/R17 (32.71)