i have a 93 civic ex. i put an exhaust on it about 2 1/2 months ago. I always notice other people that have an exhaust always have it black on the inside. My exhaust is still all shiny and clean from the inside of the tip of the exhaust. So my question is that if this is normal or could it be that i am running lean?

 

You're not running lean. You'd be rich, if anything. It just means your car is running really well (like it's supposed to), and not letting off lots of unburned hydrocarbons.

 

That's normal. If you want to see if your car is running lean or rich, check your spark plugs -- dark black plugs = rich -- white or tan colored plugs = lean. Either that or you just have a lot of carbon deposit that's being blown out.

 

would i get some better performance in my car if i made it run a little richer and/or change timing on it?

 

bump

 

anyone?