I run a 04 LLY duramax with ATS Xceleratot chip ( now stage1 ) But would like to go to stage 2 . Am thinking about installing an NBRP Exhaust , & AEM Filter . My questions are . Which System, Cat back , or turbo back, If i take out the cat , will i get Fault codes , & is it a big advantage to get rid of the cat .( i live in the mountains so no emissions testing ) is there a big difference between the XP Series T409 & the Pro Series T304. do i Only want to go single 4".. What other mods would you suggest.

 

You could get the MRBP 4" kit or the Offroad Kit that deletes the Cat.

 

You won't set any codes with the cat out. I have the cat gone & the egr blocked & unplugged and it only sets a soft code. (no light)

 

cool , thanks D-Max . thats the way am going to go .. How do i block off the egr ?

 

There is a plate available (it shouldn't cost more than $20.00) that slips between the pipe that sends the exhaust into the intake. (it's on the pass.side, back by the firewall) You just have to loosen two bolts & separate the pipes enough to slip the plate in. Keep the gasket that is in it to the "dirty" side & tighten the bolts back up. I also unplugged my egr valve, but do this when the engine is cold. (I did mine first thing in the morning before starting her up)
Any diesel shop in your area should be able to supply one for you, but let me know if you have any other questions !!

 

Thanks Again . lots of good info . will get right on it . am now looking on line for a blank plate , Will let you know how i get on . Cheers ... Roadman

 

how did u unplug the egr valve? I have mine blocked but not unplugged

also is ther ant benefits to unplugging it or is blocking just as good

 

I unplugged it in the morning when my engine was bone cold to ensure that the valve was closed. The valve is just in front of the intake plenum where the intercooler tube clamps on. (passenger side, just under the air kit tube) I think the only benefit is that the valve will not open and possibly set a code because there is no flow to it.

 

If you don't block the up pipe to the cooler, the valve can still blow open under high boost. Just make some plates out of 1/8" steel to block all 3 openings. Won't hurt anything but will keep the valve from blowing open.