Port the sleeve and add grooves for the side transfer ports. Did you try removing the carb restricter and tune it from there? Where are you lacking power? What % of nitro you using?
I have a hyper 21 3-port with turbo fan, and a hyper 21 8port with turbo fan. I just ordered the 21t head button, which engine would it be better suited for?
Hi Todd how do you rate the old .21 8 port I've got chance to get one and wondered if they still hold up today against some more modern engines Thanks and keep up the great work
The hyper 8 port was one of the first engines I owned, I learned to tune on that thing. Very solid engines that are known for carb issues. But with some fresh o-rings, the carb is great. I think it works better as a pull start basher than a bump start racer, but is certainly capable.
