I have Kpro. When my speedo shows a steady 70 mph, a GPS states that I am only going 67-68.

What is the easiest way to fix this? I would be fine with it showing 68 in that situation, so I need to change something by 2.9411764%, according to my calculations, which could definitely be wrong.

Any help?

Thanks!

 

For the map i'm running, my gear ratios are

1-3.266
2-2.130
3-1.517
4-1.212
5-0.972
6-0.780
F-4.764


I have an ap1 with stock tranny/diff, different wheels and tires than stock

 

Don't know if this will help or not...but,

On my pretty worn stock tires, I'd show 1.5 - 2 mph slower on gps than indicated. When I got new tires (not stock tires, but same sizes), that changed to about .5 - 1 mph at 65 - 70mph.

Seems the speedos are pretty accurate from the factory, but tread depth can affect it more than I'd have thought.

 

Yea, if that's the case, mine would still be off by around 2 mph at 70, which is why that's what I want to change it by

Thanks for chiming in!

 

You need one of these.
http://www.ricks2k.com/products/yellowbox.php

Or I think Modifry makes one cheaper.

 

However, you could also just bump up your tire sizes to get it right.

 

I was thinking that the kpro could adjust what I need without the yellow box, maybe if I slightly change the final gear ratio? I just don't know how all that works

 

I assume that you can probably adjust the speed that the K-Pro thinks you are going, just like you can with the FlashPro. However, according the Hondata, the instrument cluster displays it's own speed, and the ECU can't change it.

 

ah ok, i came across something to that effect relating to rsxs when googling, sucks, hopefully next tires make it less inaccurate

 

255/40/17 will solve your speedo issue. This is the same tire size as offered OEM with the CR