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WHATS THE DIFF RATIO CONVERSION

Posted: Wed Oct 18, 2006 12:52 pm
by bucketofbolts
I HAD THIS BEFORE, BUT HAVE MISPLACED IT,

I'M AFTER THE CONVERSION USED WHEN YOU PUT BIGGER TYRE'S ON A VEHICLE AND WHAT NEW DIFF GEARS YOU SHOULD USE,

IT WAS SOMETHING ABOUT DEVIDING OLD TYRE SIZE AND OLD DIFF RATIO INTO NEW TYRES AND DIFF RATIO,

I HAD A ZOOK BEFORE, THAT HAD 3.7 RATIO STANDARD, RUNNING 29'S
AND THAN PUT 5.12 DIFF RATIO AND WAS RUNNING 33'S, BUT COULD OF HAVE EASILY RUN BIGGER,

Posted: Wed Oct 18, 2006 6:32 pm
by Daisy
http://www.4lo.com/

on the navigator bar... very handy..

TOM

Posted: Wed Oct 18, 2006 7:41 pm
by Hoppy11
Do you mean this.
Formula for determining gear ratios

1) Effective Gear Ratio:
The effective gear ratio illustrates the changes that occur when larger tires are installed. For example, by replacing 29 inch tires with 33 inch tires, your 3.54:1 axle ratio will perform like a 3.11:1.
Divide the old tire diameter by the new tire diameter, then multiply by the original ratio. This will equal the effective ratio of the new combination.

2) Equivalent Ratio:
This formula is used to find the axle ratio needed to bring the overall tire/axle ratio gearing back to an approximation of stock after you have installed larger tires.
divide new tire diameter by the old tire diameter then multiply by the old ratio. This will equal the new gear ratio.

Posted: Wed Oct 18, 2006 10:28 pm
by bucketofbolts
yeah, the ratio needed when you fit bigger tyres,

it was something like

old tyre old ratio
--------- x ------------
new tyre new ratio

not sure

it basically said running 5.12 ratio in a zook, i could run 36's/37's no worries,

Posted: Thu Oct 19, 2006 12:13 am
by Hoppy11
yea, the Equivalent Ratio for 37's is 4.7, so you could have gone bigger
Hoppy

Posted: Thu Oct 19, 2006 5:03 pm
by bucketofbolts
yeah, i think it worked out that i could have ran 40'' tyres to have the same gearing as 29'' with standard gearing,