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Given the following instantaneous parameters and constants...

d = air density = 1.24

Cr = rolling resistance coeffecient = 0.015

FA = frontal area = 1.48

Cd = drag coefficient = 0.29F

G = gravity (mps2) = 9.80665

pi = 3.1415926

m = vehicle mass (Kg) = 1542

DL = drivetrain loss = .2

V = velocity (m/s)

A = acceleration (m/s/s)

F = vehicle force (KgMps2)

T = Torque (KgM)

HP = horsepower

Tire radius

Current gear and gear ratio... what would be an equation that would let me estimate instantaneous engine torque (or HP) at the wheels?

So far (I think) I have worked out these terms:

rollDrag = G * Cr * m

airDrag = .5 * Cd * FA * d * V * V

F = (m * A) + airDrag + rollDrag

Assuming that ^ is correct, this is where I'm stuck.

Any help is greatly appreciated. I'm sure I'm just over-thinking it or something, but I've drawn a blank and have been spinning my wheels (so to speak) on this for a couple of days now.

Thanks in advance!

__Known:__d = air density = 1.24

Cr = rolling resistance coeffecient = 0.015

FA = frontal area = 1.48

Cd = drag coefficient = 0.29F

G = gravity (mps2) = 9.80665

pi = 3.1415926

m = vehicle mass (Kg) = 1542

DL = drivetrain loss = .2

V = velocity (m/s)

A = acceleration (m/s/s)

__Unknown:__F = vehicle force (KgMps2)

T = Torque (KgM)

HP = horsepower

Unknown, but can be found if needed:Unknown, but can be found if needed:

Tire radius

Current gear and gear ratio... what would be an equation that would let me estimate instantaneous engine torque (or HP) at the wheels?

So far (I think) I have worked out these terms:

rollDrag = G * Cr * m

airDrag = .5 * Cd * FA * d * V * V

F = (m * A) + airDrag + rollDrag

Assuming that ^ is correct, this is where I'm stuck.

Any help is greatly appreciated. I'm sure I'm just over-thinking it or something, but I've drawn a blank and have been spinning my wheels (so to speak) on this for a couple of days now.

Thanks in advance!

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