The previous owner of my f250 decided to slap on ultra cheap headers now it sounds like crap, I have a very nice set I have had for awhile I would like to put on, think I shoud worry about any damages cause from the cheapy headers before I put my nice ones on? also it runs really rough now
The cheap headers won't hurt anything, but your nice ones will likely sound much the same. The sound, good or bad, will likely depend more on the exhaust pipes, their size, the mufflers and whether it has straight through exhaust, H pipe or x pipe. Probably needs a tune up.
Nope, just put them on, a Ford you don't have to worry about a crossover pipe, they sound just fine without it. The rough running could a a tune up, but it could also be the carb, it may need overhauled, this stuff they call fuel is murder on the rubber componets in the carb and the fuel hoses, so you might consider doing the carb and changing the fuel hoses to the new multi-fuel type. HTH
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