* The specific components used: Different cold air intakes and pulleys offer varying degrees of improvement. The quality of the MSD ignition system's installation and components also matters.
* The condition of the engine: A well-maintained engine will see better gains than one in poor condition.
* Installation quality: Improper installation can negate or even reduce performance gains.
* Other factors: Ambient temperature, altitude, and even the type of fuel used can influence horsepower output.
That being said, *general estimates* for these modifications on a 1999 Pontiac Grand Prix GTP supercharged engine are as follows:
* Cold Air Intake: A good cold air intake might add 5-15 horsepower.
* Smaller Pulley: This is where you'll see the biggest potential gains. A smaller pulley increases supercharger RPM, leading to a significant boost in power. This could add anywhere from 20-50 horsepower, *but* it also increases stress on the engine components.
* MSD Ignition: This typically adds a small amount of power, perhaps 5-10 horsepower, mostly by improving combustion efficiency.
Total Estimated Gain: Adding those optimistic estimates together, you could *potentially* see a total increase of 40-75 horsepower. However, it is crucial to understand this is a *rough estimate*. It's entirely possible the actual increase is less, and it could even be more, though that might increase the risk of engine damage. It's quite likely that the gains would be on the lower end of that range.
To get an accurate reading, the car needs to be dyno tested *before* and *after* the modifications. Only then can you know the precise increase in horsepower.
