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Old Fri, April 2nd, 2010, 04:16 PM
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Longshot270 Longshot270 is offline
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Originally Posted by cody994x4 View Post
ok i havent reprogrammed in a few days, ive been running canned lvl2 for daily driving the last time i programmed i did load a 'custom' tune adjusting my tires size to 2470, and set my gears correctly at 3.73...i was curious while i had that menu up so i viewed tire size a cpl times and the gryph kept defaulting to 2472.

i got 2470 from deducting 3% from the mm size i got from the gear ratio prog. im pegasus, i just entered 285/70-17 then took the mm value and decucted 3%. When i program the next time i will NOT deduct the 3% putting me real close to the 2552 you recommended. my stock size was 265/70-17.
Thanks
The 2472 is the value that the programmer uses after it does math and has to round numbers. The values are only 2 mm apart and only .081% off so I wouldn't worry about it.

If you use the gear ratio tool in pegasus, instead of deducting the 3% squish by hand, put your tire size and the amount of squish into the box towards the bottom. Then just write down whatever value is shown on the same line as your tire size.

If you use the forumla I put up by using the GPS, do the math by the number you entered, not the rounded value (not that it will really make that much of a difference). Also, the GPS isn't always perfect on speed unless your using cruise control on flat ground. You also have to look away from one to view the other, that is why I go by the odometer. I just let the truck and GPS record the distances and when I'm done I compare the two.
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