So you just got a stock V6 mustang and you want to make it faster. Well there are a few things you will or should know before you concider this. As im sure a few older gents on here would back me up on this post so here we go.

1. What are your long term goals for this new car?
2. What is your current budget to spend on this car?
3. Do you want to make it a daily driver? Trailer queen? or road course?
4. What is you basic knowledge of vehicles and electrical systems?
5. Do you have the time?

Alot of people want the fastest car, the best looking car or the loudest car. That is becuase everyone who owns a mustang gets the itch. And im not talking about down there, im talking about the power itch, the speed itch, the ability to take that corner at 55 and come out running.
With most major bolt on mods, you can do them yourself with some specialty tools and a good set of hand tools. Some require welding, which most places can do for a flat rate of "X" amount of dollars where "X" is the hourly shop rate.

Now were going to get into the specific mods.

CAI- Cold Air intake.

There are many different type of CAI availible on the market. The fenderwell CAI places the air filter in the fenderwell to get cool air as it rushes under the passenger headlight. This is an excellent first mod, becuase all you need are some hand tools and the intructions.

Plastic vs. Metal

These are the two types of materials CAI come in. Some people like the metal chrome brushed ones becuase it adds a nice look under the hood. Unfortunately Metal heats up from outside sources(ie., engine bay) and internal friction of the air passing through it. Plastic on the other hand stays cool becuase it is not a conductor of heat. the engine bay heat or air friction will not cuase this intake to heat up.

Mass Air Sensor and Housing

This is the peice that is inside your stock air box, and is, in my opinion, one of the bottle necks on the intakes today. The Mass Air Sensor, or MAS, measures the amount of air comming into the engine and sends that information to the ECU, where the ECU does its thing and tell Mr. Fuel Injector's how much fuel to dump in accordance to the Air Fuel mixture. Lets say you have a 3" (76.1mm) CAI and a stock MAS. Youll be pulling in alot of air fairly quickly @ Wide open Throttle, or WOT.
Lets do a in home test, if you have a cylindrical container about 6-12" long get it. If it is open on both ends, blow threw it, and what happened? The air came out the otherside with no problems, right? Now cover up 1/3rd of the other end and try again, little harder? Same concept on your intake. Still need convincing? Have you ever tried to vaccum up something to big for the vaccum? kinda struggled didnt it? exactly.

Throttle Body

This is one of those black sheep parts where bigger isnt better. 99+ Stock I think has a 65mm Throttle Body, or TB from now on. If your not turbo, supered or No2'ed this mod shouldn't be in the future until after a Power Adder, or PA.

Headers

Well, once again this is another mod that doesn't really do anything for your vehicle unless you have significant mods and are going for a PA in the future, otherwise, youll get some hourse of "Fun"

Exhaust

The second mod most people will do if not the first on their mustang. When concidering an exhaust you have to take into account that a V6 will never sound like a V8, its impossible unless you buy 2 more cylinders. The stock V6 exhaust comes out of each exhaust manifold and "Y"'s into on right after the catalytic converters. When buying a kit, you can either look for one that is complete, meaning comes with the Y adapter and passenger side hangers for the muffler and tailpipe. Or you can piece together one for a few bucks cheaper and hope it all fits. My advice, dont go cheap, becuase you get what you pay for. Which brings me to backpressure. When your choosing your exhaust make sure you dont go over 2.5" or else youll lose backpressure. without backpressure the V6 will hate you and will not run right at all. You can go bigger then 2.5" if your Turboed or Supercharged, other then that I wouldnt recommend it.

Exhaust Tips

We can get this one from our axis the ricers. Exhaust tips dont add HP they add noise, it is more of a placebo effect when you add 3.5" tips on your 2.5" exhaust, you think it is faster becuase the box says "adds upto 5 RWHP!!!" well it doesnt. But when you get in your car sounds louder then it did before, so you think its faster.

Under Drive Pulleys

There are a few out there some are cheap and some are expensive. What to look for when buying a set is the harware they come with, instructions and a package deal. RPM-Outlet has 42% MotoBlue Underdrive Pulleys, or UDP from now on, for around $208 shipped. If you have a big stereo in your car, I would say 2000-5000Watts, you really want to be carefull of the UDP's. They will slow your accessories a certain %, and could affect your cooling, charging and Air Condition. They wont affect everycar, but there is a possibility. Steeda and ARP have some 25% UDP which are a little more expensive and, well your paying for the name mostly. Installation is about a 1-2 hour job depending on your mechanical level.
Hint: A pulley Puller helps installation.