There are certain models of cars that are popular among the young street racing crowd, and those cars tend to have a lot of fairly inexpensive aftermarket stuff available for them. I honestly have no idea if the Fiesta is one of those, but I don’t think it is. Usually it’s the cheap Japanese imports that have the street mods available. Admittedly, I don’t have a lot of experience in this subject, though.
I poked around a little bit on google (not much though) and I found that there’s an engine computer change that you can make that removes a rev limiter that is applied to the lower gears. This will give you a bit more acceleration if you stomp on it from a dead start.
Apparently there’s not much available in the intake side of things, unless you want to go big bucks. There are several places selling exhaust kits though. A less restrictive exhaust will boost your power a little bit at the higher end of things.
It was a bit easier to soup up cars in the old days, as you could drop in a bigger engine (you could get a V8 from the junkyard for a couple hundred bucks back then) or a bigger carburetor to suck more air and fuel into the engine. These days, with all of the emissions controls and the entire engine being run by a computer, you can’t make these types of modifications quite so easily. With some cars, though, there are plenty of street mods available.
There are different types of tires, and the typical tires installed on cars are a compromise. They are designed to give reasonable performance in rain and snow while maintaining decent efficiency in good weather. Low profile tires on larger rims will have less “give” in them as they go around turns, so they’ll corner better. The low profile also means that there isn’t as much air there to cushion any bumps you go over, so you will feel every bump and crack in the road (as many people who have installed low profile tires because they thought they look cool have discovered). Tires with flatter treads will give better grip for performance on winding roads, but will not do very well in rain and especially won’t do well in snow, and even on dry pavement will be less efficient than regular tires (more grip equals more friction). Do you want fast straight-line speed, or do you want better handling while going fast on winding roads? Tire shops can give you tires that are best suited for the type of performance that you are looking for. You may need to switch to different tires in the winter, though, as your performance tires will likely perform horribly on snow (and probably won’t do that well in rain either).
Cars these days are also designed for maximum efficiency, so it’s pretty much impossible to modify the car for better efficiency.
You can often modify the car for better performance, and often modifying the engine computer’s programming is the quickest and cheapest way to start there. Your performance will go up, but your efficiency will go down. Your long term reliability will also drop like a rock. Drive your car gently, and you can easily get 200,000 miles out of most cars these days, even the cheapies. Drive for performance, and the car is going to be completely shot long before it even gets to the 100,000 mile mark. Performance mods and performance driving will ruin your car (I realize that this was already said but it is very much worth repeating).
