Which would work better on a black civic lx the Gold class or the NXT wax. I have already used the gold class and i didnt get great results it wasnt as deep as i would have liked. Also what are the exact steps I should use to achieve good results. Do you recommend clay bar, paint cleaner, and polish as well?

nxt wasn't as good as the gold class.
1. wash and dry car
2. clay bar
3. swirel remover
4. gold class

always worked great for my dark green car..clear coat scrub if u have hard to remove spots..

have you heard of royal blue? if not go and check it out. Forty04 uses it and it can get scratches out and what not.

I have always saw better results on my dark grey civic with the NXT gen wax VS the gold class

I have used the NXT on a Black Avalanche, and my '07 Blue Civic. It is AWESOME and lasts a long time.

if you have a lot of spots or swirls in your paint you should try the meguires 3-step. paint cleaner, paint polish, then wax. it got the bad spots out of my paint. i prefer the NXT wax. this process should give you a deep shine.

If gold class doesnt work, most probably, you're using it the wrong way..
even nxt works great on dark colours when used as directed..

'07 NHBP Si here. NXT > Gold Class. 'Nuff said. :D