We've preached it over and over again but we stand by our belief that suspension is one of the best mods you can do to your car. For under $1000, you still have some decent options for suspension. Let's start with coilovers.
If you plan on taking your car to the track, dialing in your fitment, or just want to have a slammed static car, coilovers are an amazing option. These kits replace your struts and springs for adjustable coilovers that allow you to raise and lower the car to your liking, adjust the ride, and many other adjustments depending on which coilover you get. a set of BC Racing coilovers can typically start right under $1000 which gives you a ton of adjustability. For those on more of a budget, Tein Flex Z coilovers are a little bit cheaper and still provide a quality feeling coilover.
If you just want to get lower and don't care about adjustability, lowering springs are another great option. These typically stay under $400 and will get your car lowered without having to break the bank. If you have a newer car that has adjustable suspension from the factory, these will also allow you to retain the factory adjustability.
2. Interior Mods
Now, this isn't specifically a mod but rather variations of many mods. Most things you can do to your car's interior will be under $1000. If you think about it, the interior of your car is probably what you're going to see the most so why not make it special? Things like touchscreen head units, bucket seats, or a new steering wheel can drastically increase your enjoyment when you're driving. You could probably combine multiple mods for your interior and still be under $1000 total.
Think about this for a second. Your tires are the only part of your car that are always making contact with the ground. They are arguably the most important part of your build but most people overlook them because they're too excited about their new wheels. They cheap out on their tires just so they can get their new wheels on right away. This is fine. We've all done it and we understand. But at somepoint, there's only so much your cheap tires can handle. Don't expect your second hand used all season tires to be able to hold up during a track day. Tires make a huge difference in the way your car performs and you have a lot of options under $1000.
We all love the sound of a good exhaust. It can break necks just as much as cosmetic mods will and it breathes new life into your car. Plus, you'll get a little bump in power too which we can't complain about. If you're just looking to make your car louder, a custom muffler delete can usually only costs a couple hundred bucks, but if you want a tuned sound with proven power increases, you can grab yourself a pretty good name-brand exhaust for under $1000. Not sure what exhaust you want? Go to YouTube a look up exhaust videos for your car, we'd bet that someone somewhere has a custom exhaust on the same car you have.
This last one isn't a mod but it is super important. If you have an extra thousand dollars, make sure that the things your car NEEDS are taken care of. After all, what good is the new exhaust if your car has an engine knock or oil leak. Make sure to address the things that are crucial to your car too. The mods are fun, but you can't use them if your car is falling apart more and more every time you drive.