Cal Tracs were develop for NHRA stock class racing back when you had to have stock springs in your race car, I use to race against John Calvert in stock in division 7, he has ran a 1968 428 Cobra Jet motor in his 4 speed fast back Mustang long before racing in NHRA.
He has raced the same car in NHRA SS also with his bars and stock springs long ago also so stock spring can be made to work fine
Are there better springs available today, you betcha
As far as stick shifts and radials I don't think I would do that now Buy another set of rims and bias 4 speed drag tires and go win some races