Putting a price cap on motors would change nothing.

All that would happen is the "baseline" motor sells for the cap max. Then the same company, or some after market company offers a tuning service separate form the price. Those that can, will pay for the options. Just like they do now.

Also getting blasted on the straight, actually has a lot to do with how you come out of the corner. The guys that seem faster are carrying more speed and get on throttle sooner. Speed on the straight is greatly effected by setup and driving