Jim Hall was a front runner in car design. From what I remember they were powered by a SBC (small block Chevy) and a 2 speed automatic (Powerglide)
From what I remember also, he was the first to use a movable rear spoiler and the famous vacuum car that was outlawed.
Here is a clip on one of his designs:

 

When I was a kid my slot car was a Chaparral #66
Thanks for the memories

 

You recall correctly! An iconic race car.

 

True. All of that.

 

I had one from Cox that didn't have a rear wing. The number was cosmetic .
Was this yours?

 

That's the one. My brother had #65.