It's not just a cam and heads upgrade that'll increase what you're looking for, although it will make a difference. Do it right you'll have to do a throttle body upgrade, injectors and Port match the intake if you really want to get the numbers up there to satisfy that head and cam swap. Doing that upgrade will not only increase your torque and horsepower numbers but will also extend your curve out to right further down the RPM range, you'll notice a big difference. The woods 777, 888 are both good choices as well as the T-Man 590. However there are a lot of others that Kirby or Scott will machine the heads for, to optimize flow and power for your specific cam choice.. not to mention the proper static compression set by combustion chamber size...