Recently, I installed custom headers for my 98 honda civic lx. Then i realized, that i didnt have to catalylic converter...so i put the stock (factory) headers back on the civic. now the stock headers are smoking.....so do you is it just burning the oils and residue off, or you should i be concerned

 

Yeah, it's just the oil and crap burning off. Unless you have a leak. Did you put all of the gaskets back on?

 

check gaskets. Did you reuse the old ones? If so you should probably replace them.

And you can keep the header but just get a cat and have it welded somewher in your exhaust midpipe, you'll be all set.

 

yeh...actually, i never took any gaskets off...i just took off the custom headers and installed the stock headers