torque converter and big sprocket... doable?

So already thinking about my next build. Would like to use the predator and a torque converter.

The torque converter with 7" driven has a 3.13 (low) to 1.12 (high) primary ratio, with a 10t sprocket on the jackshaft. If I am doing my math right, assuming a 26" wheel, an 80t rear sprocket would work well yielding a 8:1 secondary ratio. Final drive ratio would be 8.96:1 to 25.04:1.


This would make a theoretical top speed of 43mph @ 5000 RPM, and theoretical low speed of 6.8 MPH @ 2200 RPM.

Does this sound about right to you guys? Want to make sure I don't screw this up and order an expensive sprocket that is the wrong size.

it'll be the 99cc. there will be no intermediate jackshaft, just straight from the jackshaft of the torque converter to the rear sprocket.

thanks. I'll probably get the motor and torque converter first and see how things line up first... just would like to avoid a jackshaft if possible but we'll see.

culvercityclassic - you are going right from the torque converter to the rear sprocket? that seems like a pretty tall ratio. does it have good low end acceleration?