gx200 buildneed help/advice

[jwillis20]

I'm a new face to the small engine community and I've started with taking apart my gx200 and carb and I'm looking for the best ways to bump hp with buying the least parts as possible, I'm a machinist and can fabricate any parts that i may need but I'm at a lose for where to go from here i've removed and plugged the gov holes. but I've come to a stop because I'm unsure on what size to make my main jet and I've hear talk about the possibility of soldering a few of the holes on my emulsion tube to improve my high end and overall top speed.
if im off base please let me know this is a side project for school and would like to get it completed as soon as possible. any and all help would be greatly apreaciated

 

[Kart43]

Honda Gx200 have 20* of ignition timing, by lapping the flywheel to the crankshaft, you do not need to use a key, you can easily advance the timing to 30-32* in stock form. Start your main jet at .032", use an aftermarket air filter adaptor, and filter. You can build a simple straight pipe around 1" inside dia 12-14" long.Search forum for cam timingyou can retard the cam 2-3* depending on what you are using it for.