tire size correction question
 

This was just posted over on the F150 form but I remembered my password and wanted to post here as well..............


Guys,

I have another question before I place my order if anyone is still willing to help.

I will be specifying my new tire size on the order form for my Gryphon. Will PHP set the unit to compensate for the new tire size or will I have to do it when I receive the unit? I've read a few threads about people having issues with this.

One of the main reasons I want to get the Gryphon is to ensure my factory digital readout for speed, odometer, and fuel economy is accurate considering I have put on slightly larger tires. I have been told that all of the above will be corrected with the install.....and not just the on the unit readout, but also the truck's digital readout as well. I'm hoping this is the case and getting everything set right isn't too complicated.

Any help is appreciated.

Are you referring to the "engineering test mode"?

Ford analog speedometers are almost always high by 2-3 MPH. At least they have been on all my Fords.

Not really sure what you're asking, but I should have clarified. My speedometer is an actual gauge. However, my odometer and fuel economy readout are digital.....displayed below the speedometer gauge. My odometer and fuel economy readout is inaccurate due to the tire change. I was told this will be fixed once I install the Gryphon and compensate for the new tire size. I'm just curious if this will be set prior to me receiving the unit, both on the canned setting, as well as when I receive my custom tunes. OR, do I have to manually change the tire setting myself and will this in fact correct my truck's display?

If you tell PHP your tire size (new) and your gear ratio (stock), I'm pretty sure Bill will program your custom tunes with those values and you will not have to change anything. Not sure about the canned tunes.

Even if it does slip through the crack, these values can easily be changed (in the stock, canned and custom tunes) using the Custom Options menu (http://forum.gopowerhungry.com/faqs-...ions-menu.html).

Even if your odometer is dead nuts (as I said above), your speedometer will still read high. And unless yours is better than mine, your fuel ecomony gauge (MPG) will never be accurate, or even consistently inaccurate. On average mine is .61 MPG high and has been as much as 2.21 high.

Hope this helps.

http://www.ford-trucks.com/forums/pi...ictureid=35596

Thanks, this does help some. I just want to be sure. The Q&A link indicated that placeholder values will go in for TS as soon as I open the Custom Options Menu. I'll have to do some research to figure out how to calculate my actual revs per mile.

Thanks again.

You're welcome!

I created an Excel spreadsheet that will calculate REVS/MILE or circumference. A link is in this post: http://forum.gopowerhungry.com/gryph...html#post34767

In case you have other questions, the entire thread is here: http://forum.gopowerhungry.com/gryph...tire-size.html