I about to get a 1998 Honda prelude and need some advice to increase it hp.?

not much you can do with the auto, the H22A is actually pretty maxed out already, very well engineered. First a basic tune up plugs wires oil. USE HIGH QUALITY OIL change it religiously. I only use mobil1. check the auto fluid. make sure the timing belt was chaned in the last 60k miles. Replace it every 100k. The usual bolt on's will help CAI and underdrive pulleys are a first step. (AEM). One thing i haven't tried is upgrading the ground wires to a very heavy guage. This worked great on a mazda I had. Get a lightweight battery, the yellow tops always died on me. so stick to wet cell. you can do a header and exhaust but you won't see much gain unless you get one with a 2.5'' collector. or can afford a mugen setup. delete the cat converter but thats bad for the enviroment and you won't pass inspection. Next best thing would be lightweight wheels good tires. The basics. Then you can do upgraded cams and getting into the engine would be alot of work. You can always do turbo but again alot of work. You can also get a new hood a carbon fiber is nice and will remove alot of weight. I've had mine 7 years its a great car as long as you take care of it. And its not cheap to maintain. Goto preludeonline.com for more info.

You could do Cold Air Intake, Headers, Exhaust. You could always do a transmission swap (but that would cost quite a bit of money), or you could always lighten your car buy buying carbon fiber parts but don't be a ricer about it!

**Make sure to keep your transmission fluid changed, as Honda had trouble with their 4-speed autos for a while**