Quote:
Originally Posted by Stubby79
Looking for opinions/confirmation on my choice between the two motors.  |
Sorry for my qualification on this one - I did not look up the gearing ratios for the Firefly transmission
Assuming 5 speed manual gearbox, if you can climb the hill in 4rth gear (or better yet in 3rd gear) without going overspeed on your motor, the 7 inch will. IMHO, work fine.
Of course, the 8 inch is bigger, likely higher torque output, will take longer to heat up, etc. So you have a bit of a safety factor.
But the 8 inch is heavier so you have a heavier car .. all things being equal you choose the lowest weight option, right?
I don't think you will overheat your 7 inch motor on this trip. I have hauled a trailer with a 48V DC club car (800 lbs with leadies) for a few minutes .. maybe 5? .. with the motor amps at 200+. It was a not-so-quick walk. The motor had NO air cooling since it was turning so slowly. The DC motor is a bit smaller than 7 inches, maybe 6.5 inches, single speed gearbox. The motor was hot to the touch, but you could leave you hand on it without getting a burn.
My point is that you will be doing about 180 amps for the hill at 156V for less than 5 minutes .. that should not cook your motor. The club car was not putting out the same power, but it was taking similar amps, which is where you get the heat from
