Genuine GX240 in G2/G9 what budget upgrades

Hi,

I've got a Yamaha G2/G9 (not sure what it really is) with Honda GX240 installed it. GX240 was free with very few hours on it. I received the cart for virtually free with no motor to replace my old '91 Marathon two stroke. Anyway, I'm ordering a Comet 780 for the primary clutch.

I've pulled the governor on the GX240 and I have a GX390 carburetor with free flow exhaust and car muffler. I want to get a little more performance out of the 240 without spending much money as the plan is to get the VC460 once I finish upgrading the suspension and other general maintenance and safety issues. The cart is mainly used off road, loaded with gear and people on hilly and muddy terrain. Torque is important. Cart runs 23" tires with a set of 25" tires waiting for a wheelbase extension.

What direction should go I with the 240 knowing that a 460 is planned for 2017/2018?

I was planning:
GX390 stock cam
Re-jetted stock GX390 carburetor with free flow airbox
custom car muffler exhaust similar to sho but swing arm mounted.
Stamped 1.3:1 rockers (Where can I get these? Are GX200 ones different?
35# HD valve springs
Heavy Duty Chromoly Pushrods
8 degree timing key
stock rod
uncut head

Ryan