Questions about tire size and custom settings.
 

Ok. So my new tires should be here tuesday.:woot: I am going to a 305/65/18 BFG AT. My current custom tune should be for 275/65/18, which means I need to make some adjustments. What all do I need to adjust in the custom options, besides the tire size? What values automatically change as soon as I open the custom settings option?

Nice choice on the tires. When you open the custom settings you will want to change the tire size and then confirm that the gear ratio is correct. Some times this defaults to a false place holder.

Thanks for the reply.

Is that the only thing that defaults back? I thought I read that there was like two other things. I couldn't find a thread on it.


Any idea on what the tire size value would be for that size tire? Isn't there a chart or calculator on this forum?

I would start with 2614mm (4% squish) and then adjust up or down from there.

Edit: Here's another link...http://forum.gopowerhungry.com/gryph...tire-size.html

^ What they said. :cheesy smile:

Just make sure you click "Load Previous settings" so that nothing else gets messed up.
If you have pegasus that has a good tire size calculator in there. It's hidden in the gear ratio calculator, that'll help you get it close. If you have a GPS then you can get it perfect. Write down the tire size that you put in there then clear the odometer on the truck and GPS, drive at least 10 miles and then take the numbers and do this:
Truck odometer divided by GPS odometer multiply that by the tire size you were using. That'll have you dialed in perfect in no time. :thumbsup:

If I have just been using Bill's custom tune, I shouldn't have any previous settings right?

If you are using the custom option file with a custom tune for the first time then no I don't think you'd need to use load previous settings.
But anytime after the first time then yes use the load previous settings.