What's the first mod I should install on my Mustang?

Have you just bought a Mustang andare now wondering what you should do to it first? Well, it's a question we get asked quite often. While the answer does vary from case to case, I have a few suggestions and explanations that might help you in your quest for speed. While we will deal with Mustangs in this guide, many of these tips will translate to other makes and models of rear wheel drive vehicles out there.
First, the question I have for the new Mustang owner isalways (in the case of a used Mustang), "What does it have done to it already?" Most used Mustangs have little tweaks and tricks already performed on them as that is pretty much what these cars are made to do -- be improved upon. Sure, Ford did a decent job from the factory but, let's face it, more is always better! If it's new well, let's think of it as a blank canvas and get started modding!
The second question is then "How much would you like to spend?" Budget is the next factor in the progress of your Mustang from tame to wild.
The third question I usually ask is, "What's your ultimate goal with the car?" That will help narrow down parts you should buy now and not have to change them later down the road. Many times, however, people start with an idea of just a little bit more power and end up with the desire to increase the output of their car by 100 or more horsepower. I am a person who fits into the latter category :) My daily drivers always start life as such and then I'll just put a cold air kit on. Then, maybe a small nitrous kit. How about some heads? Well, I need a new exhaust now, don't I?And so on!
Alright, enough of the questions! Let's get to some answers.
Tune up!If you just bought a used car, the first thing I'd regemend you do is a simple tune up. You'd be suprised at how much power you could find by replacing spark plugs with worn electrodes or badly cracked and split wires. How about a fuel filter? When was the last time it was changed? Definitely do an oil change and let's move on!
Chassis StrengtheningSubframe ConnectorsThe first regemendation I always make to Mustang owners is toinstall a set of subframe connectors on the car. If you were building a house, you wouldn't start laying the first floor down without pouring the concrete and letting it cure, would you? Well, this works the same way. Ford (and most other manufacturers) did away with full frames in these types of passenger cars and went with Unibody Construction for a few reasons. It's a weight saver, you get better clearance under the car, allowing you to make the vehicle lower to the ground and, of course, it costs less. So, instead of a full rigid frame from front to back, you have a subframe leading from the front of the car to the middle of the front floor pan and one going from the back of the car to the beginning of the rear floor pan. Yup, the floorpan is now a structural piece! I've seen cracks in the floor pans of Mustangs measuring6 inches. I've also seen cars with multiple fractures in the floor pan from areas under the front seat up the transmission tunnel and many more. Convertibles are even more prone to twisting as now you've taken the roof out, too! Needless to say, subframe connectors are the place to start on any Mustang. They're cheap, with full length connectors (running the entire length of the car) costing the most with a range of $109-$130. Installation will cost more than the part as it requires a person who can weld decently and a proper facility. Don't forget to pull the carpet up and bungee it or clamp it over the center console! Don't want it to catch fire!
Torque Box StrengtheningWild Rides, a gepany out of Farmingdale, NJ, came up with a simple and strong way to fix another area where the Mustang is structurally deficient -- the 'torque box'. Basically, the torque box area is where the rear control arms connect to the chassis. The uppers are merely connected through some stamped steel that is tack welded to the sheet metal of the floor or upper sear back area inside the car. The lowers are slightly better but not nearly good enough to serve our purpose! These kits are cheap insurance at $109 a piece or $169 for the set of uppers and lowers. The labor is a little more but you can do these yourself in a driveway witha socket set, floor jack, jack stands and a friend to help hold and mark things. That'll save you money as they don't have to be welded in (although you can if you choose). Wild Rides is the original maker of these kits -- they call them the battle boxes as that's what you'll be ready to do when they're installed -- battle it out on the street or the strip!
While so far, the mods aren't sexy as they don't make you go faster, they're definitely necessary -- and inexpensive, for the most part. It's like upgrading brakes -- most people put that off to last, even after upgrading wheels when it should be one of the first mods. We'll skip those for now as, I know, mentioning brakes islike pouring water on the go fast fire!
Rear End Gears (Ring