when changing a truck to dual exhaust from single......i am putting on two long tubes straight into the pipes but how to install the long tubes? I have a stock 01' 4.8 silverado so what kind of headers should i get as far as egr/air goes? What do i need to install the long tubes before doing all the piping? (as far as gaskets, etc.)

 

Your truck does have an egr valve but that is not an issue. You can always remove it, tune for it and get some headers without egr. If you already cut the stock Y pipe for a true dual exhaust, consider gettint a replacement y pipe to make single back again.

 

outside of getting an sts, why would going back to single be advantageous

 

Not sure... He is the one wanting to go back back to single. Just offering an alternative for him.

 

It sounds like to me he wants to go dual....

 

i'm definitely wanting to go dual......anyway, how do egr valves work?....explain how i might remove them.......as far as my stock oxygen sensors go, to keep them happy a pair of o2 simulators would keep them from throwing codes right?

 

The egr shoots burnt gases back into your intake manifold and 're' cycles them. Sorta like running a small camshaft with very little overlap. Overlap forces out spent exhaust gasses that would otherwise be caught in the combustion chamber and re-burned. Helps with emissions.

They sell block off plates and a plug in for your intake manifold for maybe 17 bucks, or you can make your own at home depot. I believe ls1speed sells them. That is what I currently use. I believe you may get a SES light in your dash. You'd need some sort of tuning. (not positive abotu the ses light...to long ago)

I didn't have any luck with the simulators....Save some cash and buy a nice tune. That would be my opinion, but yes the 02 sims should take care of it.