Silvercomet
Just a thought , since you stated you're on a budget.
Maybe try the Venus with your 46 off the US 40,for now.

You could then move up to a bigger motor when you could afford it. I'd probably even leave the cowl off until I changed the motor. That way you wouldn't cut the cowl for the 46 and it be messed up for the "new motor"

The 46 (as stated before) will not be all the power you want , but It'd fly probably good enough for you now. It'd be good enough for me anyway. :-)

FYI the ys63 is a 4-stroke. The muffler that comes with it is all you need. The tuned pipes referrred to boost the power in 2-stroke engines. Pipes are used on some 4-stroke engines , but it's my understanding that mostly for sound muffling - not performance.

Eddie