Back in it's day I had a series of MK Arrow 40's with 6.5 K&B pylon motors with big carbs and Perry pumps and tuned pipes. Incredibly fast. I built these pretty light back then too. I won a couple club pylon events as well as fun fly events with them. One in particular was at the "go" signal run from 20 feet to the plane start it, take off, one loop and land. You had to land on the pavement and stay on it, if the motor quit you had to demonstrate it would still run with the same prop. (no broken props allowed) Catch was all special features such as retracts and flaps had to be demonstrated. Mine had the slotted flaps and retracts so I was one busy puppy. As I recall it was 28 seconds.

I also had a series of Dirty Birdy 40 and 60. I actually like the DB better as they were smoother flying.