Estimating Flywheel Torque At A Known Rpm; Calculating Compression Ratio - Calculated Industries Hot Rod Calc 8703 User Manual

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2. Calculate the HP at 3800 RPM:

At 3800 RPM, when your 400 CID engine is producing 445
pounds-feet of torque, it is also producing about 322 HP at the
flywheel.

Estimating Flywheel Torque at a Known RPM

If you know horsepower output at a specific RPM, you can
calculate torque at that same RPM.
In this example, your 400 CID engine produces 366 HP at 5400
RPM. Calculate the torque for the same RPM.
KEYSTROKES
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1. Enter your HP and RPM:

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2. Calculate the Torque at 5400 RPM:

At 5400 RPM, when your 400 CID engine is producing 366 HP, it is
also producing about 356 pounds-feet of torque at the flywheel.

Calculating Compression Ratio

Compression ratio is the relationship between cylinder volume with
the piston at bottom dead center (BDC) to cylinder volume with the
piston at top dead center (TDC).
44 — H R
OT OD
C ™
ALC
RPM S 3800.
HP MSA 321.966
DISPLAY
HP S MSA 366.
RPM S 5400.
LB-FT MSA 355.977
0.