A Stage 1 upgrade consists of the following bolt on performance upgrades:

• Free flowing exhaust pipes.  (Full set or Slip On mufflers)
• Air Cleaner Upgrade
• Carb Rejet or ECM Remap depending on whether it is Fuel Injected or not.
• Ignition upgrade if applicable.

Stock Harley Davidson exhaust pipes do not flow that well compared to the performance pipes that are available from companies like Vance and Hines, D&D, Santee and many more.  Pipes offer a few other advantages as well.  Aftermarket pipes typically "look" better than stock pipes and they sure do SOUND a lot better than factory pipes.  So really you get more flow, more sound and better looks out of a set of pipes.

When you talk about power, do you mean torque, horsepower or both? Torque is twisting power. It's this low-rmp twisting power that gets you moving. Horsepower is the higher-end spinning power that keeps you moving.

If you look at the difference between a Harley-Davidson V-Rod and a regular Harley Twin Cam 96, you'll see that the V-Rod with its' 1200cc engine puts out a lot more horsepower than the Twin Cam 1584cc, but puts out less torgue.

The V-Rod puts out this horsepower buy spinning faster. The V-Rod is able to spin faster because of its' four valves per cylinder and dual overhead cams. Basically it's because of the V-Rod's overall breathing ability.

Remember torque is the twisting/pushing power that occurs at the lower rpm range and horsepower occurs at higher rpm ranges. For most Harley-Davidson riders, it make very little sense to try to increase engine performance to the 4,000 to 6,000 rpm range, when most of your riding occurs between 2,000 to 4,000 rpms, especially when doing so negatively effects torgue. You can get good low to mid-range Harley-Davidson performance without a lot of modifications.

Right... But remember one thing, If you want something good then you will have to give up something. I am telling it because it will cost a lot of extra money...

It is great. It is also true that it costs a lots of money.