Let's see given the Tires wern't rated safe at much of Any Speed, the safety equipment was a (optional) Leather Skull Cap and the Brakes on todays Shifter Karts are vastly superior to what was on that Car, I'd have to say at any speed over 50mph or so That Puppy is Still a Monster!! Good to see you returning to Cars. The Street Cars were Neat, But Road Racers of any Vintage, YEA!