[5speedGen1]

The best thing to do is do a B20 Vtec. Depending on the milage of your Crv you might want to pick up a B20 imported from Japan. You can find them for $400-$500 and they are all around the 50,000 mile range. The find a Vtec head (b16 or B18). Combine the two and an easy 200 hp to the wheels. There are other supporting things that need to be done like ECU and running a wire for the Vtec so it isn't for the novice. There is a huge amount of info about this combo on sites like Honda tech. I hope this helps some.