X2 on what Brian said. Lately we've been trending towards LOWER HP motors. Gobs of power is always fun, but isn't always consistent. Small tight bullrings corner speed is king. Hard to do sometimes with big HP and torque unless ur absolutely KILLING tires with prep. 1/5 mile or more with high bite tho, the biggest motors we have are bolted on. 1/10 mile or less and we try to stay around 30 HP.
There is a thread on about the Vegas 440, www.vegascarts.com buy the stock engine and add billet rod, piston, and flywheel for reliability and a mild high duration cam should be a little more than 30hp I would think.jmo