Turbo the D.
I'm going to tell you now, if you're listening to friends or other people saying get a cold air intake, headers, exhaust, or a cam and all that... You're not going to get any power. You can say you do, but all you're getting is noise and retardation.
It's a Civic, not a Mustang, bolt ons don't make much power since the potential is bottlenecked in the ECU and the motor is already maximizing it's potential as an N/A economical engine.