User guide

HOT ROD CALC™ — 39
gear is direct drive and therefore would be the same as the final-
drive ratio you are solving for.
KEYSTROKES DISPLAY
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0.
7. Enter your RPM, cruising speed of 65 MPH:

RPM S 3000.

SPEED S 65. M PH
8. Calculate the final-drive ratio:

(Final-drive ratio) GEAR 3.57 RATIO

(Manual trans final-drive ratio) GR-M 3.529 RATIO

(Auto trans final-drive ratio) GR-A 3.582 RATIO
Repeated presses of

will toggle through the inputs and outputs,
starting with the RPM input.
From the above calculation, it is estimated that in order to reach
3,000 RPM in 4th gear at 65 MPH, the LX will need a final-drive
ratio of 3.57. And for the users who have experience with the Larry
Shepard correction method, your calculator also shows a manual
transmission (GR-M) final-drive ratio of 3.529 and an automatic
transmission (GR-A) final-drive ratio of 3.582.
Instead of changing your final-drive ratio as in the previous
example, you could have solved for the performance another way –
by changing the tire size. Using the known parameters of 65 MPH,
3,000 RPM, and our current final-drive ratio of 3.08, calculate a
new tire size that will give similar results as the final-drive ratio
change in the previous example.
KEYSTROKES DISPLAY
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0.
9. Enter your RPM, cruising speed of 65 MPH, and gear ratio: