[WildBillyT]

Originally Posted by Pampered-Z

Like everyone said. TB bypass is probably only worth 1-2 HP for the first few minutes the cars running. After that the TB is still getting heat soap from the engine. If you drag race and the car has time to cool down then it would be of some value, but if you run round~robin the bypass would be negated. Still, it's a $2 fitting and 2 - $2 hose clamps you can get an any hardware store. If your just a daily driver then don't bother with it.

AIR, does nothing to improve or reduce HP. The gains you'll see is from the weight reduction.

IAT box is just a cheap way to gain a bit by tricking the computer. They are suppose to work, but why not just spend a little more for a good custom tune that will yeild more HP.

The real key to HP and performance is getting the engine to breath better or reduce weight,

The free mods that seem to have value are: Cutting additional holes in the air box, getting cold air into the engine. The "Pert shampoo" plug in the elbow. Do a search for the homemade CAI some of the guys here built. That's good low cost HP gain! and the LS1 motors you can cut the EGR tube back.

Don't forget about basic car maintainance either! air cleaner, plugs, wires, fuel filter and PCV valve. Think of this as restoring HP # as you'll loose performance as these parts get old.

Another good cheap mod is to replace the bellows with a smooth coupler.