In a message dated 96-12-14 17:42:13 EST, rberg@comet.net writes:
<< ..... '73 Midget. ..... the speedo is WAY off. ..... I jacked the car up,
locked up one wheel, spun the wheel and counted drive shaft revolutions.
Here is the results:
WHEEL 25 turns -- PROP SHAFT 48 turns What rear end do I have???
The speedo reads about 20% slow.....i.e at 55 the speedo reads 45 at 25
the speedo reads 20. ..... >>
Ric,
Because you stoped one wheel the prop shaft only turns half as fast, so
for the true ratio, double the prop shaft rotations. 96/25 = 3.84:1
Assuming you counted properly and the prop shaft came out within 1/8
turn of the original starting point, any error should be within 1 part in
48x8, or within .0026 parts of 3.84, or +/- .01. So the final drive ratio
should be between 3.83:1 and 3.85:1.
Beyond that, I'm not a Midget guy, so I don't know what the ratio should
be.
Barney Gaylord
1958 MGA
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