HI Guys,
Yes indeed, the Cox Venom was the fastest Cox engine. It had better cylinder porting, a lightened piston, a better balanced crank + the nylon reed retainer (although not faster) was more reliable. The ONLY modification I do is to replace the original piston with that from a TeeDee. And then ONLY IF the original piston has failed. The (still current) record holding engine was indeed stock including the glow plug. I dis-assembled it right at the Nats to prove it...
The major dissappointment with the Venom was it's fragile piston. Sadly, if they had just made it per Larry's direction, it never would have failed. My original Venom prototype (from Larry) is still going strong with all original parts. I keep it as a 'reference engine' & mostly just bench run it. It's always packed in my mouse kit as an emergency #4 back-up engine. (Any AMA NATS is considered an emergency...!)
I'm green with envy not being able to enter the 'hollow log' event!