Nice!
I know these engines will do fine on short tracks, maybe even better because the bottom power but I think on large tracks there is a rpm shortage to keep up the faster motors.

You can take a look to the Novarossi Basic, the 3 ports and the 5 ports have a very good price and for a bit more you have the 7 ports version. With a bit wider budget you can take a look to the JP P7L which isa very competive engine for its price.