I have a 1975 Duster with a 225 and need to know.
Thanks

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Ronnie
http://www.cardomain.com/ride/2714941

If I recall right......
both wheels off the ground, spin one wheel, count rev's of yoke....
if both wheels spin in opposite directions X2 your count (open),
if only one wheel is spinning use that (open),
if both wheels turn same direction
use that number (suregrip).
helps to mark both the tire and yoke....

3 and 1/4 turns will be around a 3.23
2 and 3/4 turns will be around a 2.76

So with both wheels turning opposite a 1 and 1/2 spin
will be a 3.00 something, 1 and 5/8 turn will be close
to a 3.23, ect.......

course you can always look for that tag on the rear
cover, but there often missing and sometimes even wrong
if the rear has been opened......
or pull the rear cover (8.25, 9.25 rears)and look for the stamp on the
ring gear

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http://imageevent.com/jeffc
62 D100 225 3sp lwb
64 D100 A318 727pb custom lwb
66 D100 A318 4sp lwb
68 D100 B383 727 swb
65 Belveder A318 727 4d
65 Dart GT LA273 2bbl 904
73 Scamp 225 2bbl 4spOD
Old iron or no iron

looks like he covered it! I need to learn to type faster

TF

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Even in moderation i am excessive!

Check out this thread:

http://www.slantsix.org/forum/viewtopic ... atio#96927

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David Kight
'62 Valiant Signet, White
'98 Dodge Dakota
'06 Jeep Liberty

Growing older is unavoidable but growing up is strictly optional.

If all original with an automatic Im betting 2.76

3 1/2 turns will be what I've got, a 3.55

And my engine SCREAMS at 90 MPH!

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'74 Duster w/ HEI ignition, beat to snot suspension, A904, 8.25" 3.55 SG rear, still being tuned up and gets 17 MPG

Know how they always build a better idiot? That's me

Standard-equipment ratios in '75 were 3.23 with stick-shift, 2.76 with automatic. Special-order ratios were available.

You may find a tag with the ratio affixed under one of the diff cover bolts, or you may not. It's easy enough to check the actual ratio of the actual axle in the car:

Lift one rear wheel off the ground. Chalk the inboard sidewall of the tire that'll turn and block the other tire (or just don't lift it up) so that it can't turn even a little bit. Trans in Neutral, parking brake released. Turn the marked tire through two full revolutions and count quarter-turns of the driveshaft by watching the rear U-joint caps as the come to face the pavement. Divide the number of quarter-turns by four to get your ratio.

16/4 = 4 = 3.91
14/4 = 3-1/2 = 3.54 or 3.55
13/4 = 3-1/4 = 3.21 or 3.23
12/4 = 3 = 2.93 or 2.94
11/4 = 2-3/4 = 2.71 or 2.76
10/4 = 2-1/2 = 2.45
9/4 = 2-1/4 = 2.26

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一期一会
Too many people who were born on third base actually believe they've hit a triple.