what kind of engine can fit in 2002 Chevy Caviler

Your car is an extremely poor candidate for hot rodding. You could spend thousands of dollars on it and no one would even notice it being faster. Sorry.

i want a engine that look cool and make faster

and that cheap

You can fit a 3.1 liter engine in there, or a 2.8 MPFI, or a 3.8 if you like.

For my part, I'd go with a 2.8 Multi-Port Fuel Injection. You can always modified it using an AR-50 turbo, and it will give you the thrill you're looking for. But remember, you'll have to change the ECM as well, because what works with a L4 doesn't work with a V6. So prepare your wallet for a $2000.00 and upwards expense. And you'll probably have to change the complete power-train in the process.