hey,
i have a 1992 mistubishi eclipse 1.8l manual. i want to make this car realy run but i dont know what size engine i could put in it. that and what modifications i could do.if you could give me some advise on how to make it the best it would be very helpful.i dont have a set spending limit but i dont want to spend too much. i just want the car to be fast and sporty. its currently at a body shop for ground effects and a new paint job. so my next step is under the hood. you think you could help me? 

But there are a few upgrades you can do for your car. First, you need to allow the car to breathe better. There are items called Cold Air intakes. All those are are straighter hoses that goes from your air filter to your throttle body. Also, a more free flowing air filter will help. K&N filters are the preferred air filters of many Eclipse owners. Once the car can breath in better, it needs to exhale better. You can bolt on a more free flowing exhaust system. Note, loud exhausts do not mean more power. You can get a larger exhaust without the loud noise, and still get the same performance.

Those are the two most common (and least expensive) ways to get more power. But if you want a lot more power, you will have to upgrade your engine. By that, I mean that you need a different engine. The 2.0 liter turbo engine should fit in your car. And with the 2.0L engine, you'll need the transmission that goes with that engine. Another engine and transmission will set you back a bit, but the money can be worth it if you want signifigant power increase. There are not as many performance upgrades available for 1.8L engine, but if you upgraded to the 2.0L engine, there are LOTS of performance upgrades.
Good luck!