I have a 1996 Honda Civic and whenever I try shifting out of first gear it makes a rattle underneath the car? It doesnt happen every time.. Just every so often.

 

could be your shift linkage against your exhaust.. do you have an after market exhaust or an after market short shifter?

 

No... I havent got there yet. lol how can i get more power out of it? i have a 98 kia sephia that blows this car out of the water...

 

Can you feel this "rattle" in the shifter as a vibration?

Making the car "fast" is a relative term. Tell us what "fast" means to you.

Usually, these D series motors will not respond well to modifications unless you are boosting it, or swapping it out for a bigger motor.