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Old Thu, December 25th, 2008, 12:10 AM
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Jackpine Jackpine is offline
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Location: Among Elk, Deer and Javalinas on the Mogollon Rim in Aridzona
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Quote:
Originally Posted by Power Hungry View Post
Load Previous Settings is used to load the last custom settings you made. This is so when you change levels you don't have to go back through and re-enter every change you made. If you haven't made any changes to begin with, there's nothing to reload.

As I've mentioned before, the default tire size and gear ratio that is displayed in the custom options HAS NO RELATION TO THE ACTUAL TIRES ON THE TRUCK. They are some made up, arbitrary number. You have to put in the correct size for your your tires and you must also put in the correct gear ratio.

Squish is a relative term used to describe the phenomena that occurs where the tire patch contacts the road. Tire inflation, tread compound, tread pattern and aspect ratio (sidewall height) all have an effect on squish.

For a 55 series tires, I would use a 3% squish value since the deflection of the sidewall is going to be considerably reduced compared to say, a 75 series tire. For the size you specified, you should be around 2517mm.

Take care and Merry Christmas!

At the risk of I'd like to mention that the tire circumference adjusted for "squish" is just a "ballpark" starting point. I had to make several changes to mine to get the speed (shown on the Gryphon) and the dash odometer to read correctly. With my 275/65-18 Goodyear Silent Armor tires, at the recommended 40 PSI, I use a value that is equivalent to 7% squish in the Gear Calculator application. And, the truck's dashboard speedometer reads 2 MPH fast at 75 MPH, but the odometer is accurate.

Merry Christmas everyone. We just got back from one of our Granddaughter's birthday day. She was born on Christmas Eve!

- Jack
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