DoctorDiff
Well-Known Member
In addition to a 3.54 ratio, some 8.75" rears came with 3.58 gears.
Rear end selection help and opinions
- Thread starter LivewireBlanco
- Start date
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Rusty, Hate to disagree with you but my 8 3/4 is running 3:55's
AJ/FormS
68 Formua-S fastback clone 367/A833/GVod/3.55s
- Joined
- Jan 19, 2014
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It depends on the actual C&P tooth count; for instance;
09/32 is 3.555 rounds to 3.56
10/35 is 3.500 .............. 3.50
11/39 is 3.545 rounds to 3.55
12/43 is 3.583 rounds to 3.58
13/46 is 3.538 rounds to 3.54
14/50 is 3.541 rounds to 3.54
not all combinations exist.
As the tooth count goes up, sooner or later it won't fit in the given case anymore. Sorry I don't recall what fits in what anymore.
The difference in % is almost miniscule; from a quarter of a percent in the bold ones which is 8 rpm@60 mph, to
1.01% between the min/max which is 33 rpm@60mph, it pays to shop......
09/32 is 3.555 rounds to 3.56
10/35 is 3.500 .............. 3.50
11/39 is 3.545 rounds to 3.55
12/43 is 3.583 rounds to 3.58
13/46 is 3.538 rounds to 3.54
14/50 is 3.541 rounds to 3.54
not all combinations exist.
As the tooth count goes up, sooner or later it won't fit in the given case anymore. Sorry I don't recall what fits in what anymore.
The difference in % is almost miniscule; from a quarter of a percent in the bold ones which is 8 rpm@60 mph, to
1.01% between the min/max which is 33 rpm@60mph, it pays to shop......
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