performance difference

[dirtwarrior]

I am going to get a kit for my trike. I am undecided on a tanaka 40cc rated at 2.2 hp or a 50cc honda or hs rated at 2.6 hp.
I know the tanaka is very loud but will an expansion chamber make it quieter. Properly jetted to the pipe and low restriction air filter what would the hp be?
Same with the honda or hs engine?

 

[Mean.motor]

I do know that an expansion chamber will not make things quieter, especially going hard on the throttle, unless the expansion has a silencer attached to the end. Not sure about HP though, at least a 5-10% increase.