At 09:51 AM 3/27/99 -0800, you wrote:
>Jim,
...
>BTW, I'm surprised you are still running the 2.88s, especially with the new
>overdrive tranny. Have plans for a new rear end with a limited slip??
..
>Bob
I have mixed feelings about the overdrive transmission.
The low gear is 3.29 to 1. That seems to be way too low for
a high tork 351C in a lightweight Tiger. I just barely get started
before I have to shift to 2nd. However the numbers below seem to
indicate this is close to correct. 2nd gear at 1.84 is a big drop
from 3.29, Third is 1:1 . OD is 0.81
The following general equations may help explain why I am still using a 2.88.
Note * indicates multiply.
MPH in 1/4 mile= 10+(221 * Cube root(HP/ weight with driver in pounds)
Example: 350 HP, 2600 lbs gives 123.26 MPH.
Required Rear end Ratio= (RPM * Tire Diameterinch)/(310 * MPH)
Example: 5500 RPM, 21" tire @ 123.26 MPH gives 3.022 rear.
Optimum First gear Ratio= (Tire Widthinch * MPH)/HP for manual transmission
Example: 9" wide tire, 123.26 MPH, 350 HP gives 3.169 low gear.
Optimum First gear Ratio= (Tire Width * MPH)/(1.8* HP) for automatic
transmission
Example: None
James Barrett Tiger II 351C and others
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