Huffy 550 Performance Motor Kit option-set-449227-select-1 or 18v or 24v SLA

or 18v or 24v SLA Batteries (select when you purchase)

and low friction race grease

And even so you do run the risk of blowing motors

See video below on how to install gears into your gearboxes

The axle hole is 19

Huffy 550 Performance Motor Kit option-set-449227-select-1 or 18v or 24v SLAThis is a matched pair of 550 High Performance motors for Huffy cars that started as 12 volts. These motors will add a very noticeable 15% speed increase over the stock motors plus can be boosted up to 18 volts for even more speed. With each pair you get: * Steel ball bearings inside the motors for reduced heat buildup and higher rpms. * Torque Sleeves around each motor to add more low end power. * Built in Cooling Fans. * Spade Connectors for quick