My promo kart came with a B/S 3.5? Any hop up tips?

[Mike]

Yep, my promo cart came with a 3.5hp B&S. (It was a promo for a B&S dealer). Any ideas to make it run better/faster?
I have added Royal Purple motor oil, an E-3 spark plug, and a high flow KNN style air filter.
I also have some unused 8mm spark plug wires and was wondering if I could use a spiral core wire on the B&S motor?
Please help.
I NEED SOME ADVICE!
I want to get at least 4 hp out of my 3.5! :)

[schatten]

aftermarket exhaust

[suprbean]

you can check HERE to see what they got. they offer hop up kits!