Fox Figuring Out Gearing, Help Please

FoxMustangLvr

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Oct 14, 2012
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Spokane, Wa
Allegedly my 88' coupe has 3.73 gears in it. Even the tag says 3L73. However when I jacked up the rear end and rotated the tires one time I counted 3 1/8 revolutions of the flange (no DS installed at the moment). I don't think the absence of a drive shaft would throw it off so I'm thinking 3 1/8 turns is really 3.08 or 3.27 gears??

It's the 8.8 rear end, V8, trac-loc etc
 
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Allegedly my 88' coupe has 3.73 gears in it. Even the tag says 3L73. However when I jacked up the rear end and rotated the tires one time I counted 3 1/8 revolutions of the flange (no DS installed at the moment). I don't think the absence of a drive shaft would throw it off so I'm thinking 3 1/8 turns is really 3.08 or 3.27 gears??

It's the 8.8 rear end, V8, trac-loc etc
the diameter of the tire has to be considered too. Remove the tire, then do your rotation test.
 
One complete rotation of the tire 360 degrees is the same no matter what the diameter of the tire is. One revolution of the tire should yield "x" numer of turns of the pinion yoke this is equal to your rear end gear ratio. I usually use the valve stem as a reference and mark the pinion at let's say 12 o clock. 3 and 1/8 turns leads me to believe 3.08 gear set. Just think how many opportunities existed to change the gears over the years.
 
True. In my opinion 3.08's are throw away gears. I have a 3.73 complete axle drum to drum that i'll swap in. Although the gears whine a little in it i'd rather have 3.73's that whine at me over 3.08's that i'll whine about not being enough giddy up. The whine only occurs when I let off the gas pedal and coast and the person that installed them said he'd fix the whine for free.
 
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Put a turbo on it, keep the 3.08's


I am a problem solver!

I hope my HP bug never gets as bad as yours and 84ttop or i'll have to sell my wife on the local BLVD to support it. I'll have to settle with squeezing all I can out of N/A for now.

Besides I like your motto, it's easier to drive a slow car fast..............