DC Electric Motor Voltage/Current

[Pete in CDA]

Good Day,

I have an older Prestolite DC motor that is installed in a 1979 Ford Fiesta.  I want the Fiesta to be capable of getting on the local freeway.  I've seen where motors are somewhat "Flexible" when it comes to the voltage in.

It says (about Power),

Nameplate 10hp
96v/200 amps
96v/400 amps
Voltage Continuous 96 vdc
Current continuous 180 amps

The questions I'd like to pose are;

What's the highest voltage I "Should" put into it without pushing too far? (What I'm wanting is 120 vdc)
What's the highest current I "Should" put into it?

Pete in CDA