Torque for forcing a ball through two wheels

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Homework Statement

There's not a given problem statement exactly, it's part of a project I have. I'm designing a tennis ball machine to throw balls out using two counter-rotating wheels. The wheels are 4" in diameter, the balls are between 2.575 and 2.7 " in diameter, the wheels are 1", and it takes 87.050 lbf to compress those balls by 1"

Homework Equations

I know Torque is F * distance, and there's also H = Tn/63025, where H = hp, n = rpm, T = torque in lbf-in

The Attempt at a Solution

I've been trying to calculate the torque needed to spin these wheels and such, but either the torque I'm getting is very very high, or I'm using the equations wrong.

My professor said that Tmotor = I*alpha + Tball, where Tball was F*(.5*gap)*radius
Just finding Tball is 87.050 lbf*(.5)*(4") which gives 174 lbf-in, seems way too high.

 

[Valkarie]

In my other attempt, I used the equation H = Tn/63025 to try and solve for torque. I know it'll be spinning at around 450rpm, and I estimated the horsepower needed to be 1hp. So I set up the equation as 1 = T*450/63025, giving T = 14 lbf-in. Again, this seems way too low. Am I using the equations wrong, or is there something else I'm missing? Thanks in advance.