Well, Ive ordered the 6.0 LQ4 to replace my 5.3 and that should be going in next week. The Kenne Bell twin screw will be reinstalled onto the 6.0. I have heard that the exhaust manifolds are pretty efficient on these engines. Thinking of changing the Y pipe and going with hi-flow cats to complement the Cat back. It looks quite restrictive so that might be the best bang for my buck. Anybody have any input. What are the potential HP gains. Will this setup net 400rwhp!


Also it appears that the stock CAM might be the best option for FI. Is this true.

 

since you have an ECSB, you might try getting a hold of a stock HD exhaust system. Duals all the way back to the muffler

 

There are some cheap,good fbody cams that would be better than the stock 6.0 cam if you are on a budget.HD sysytem will not bolt up,different frame different trans.I had HD cats grafted in and a custom 3" duels to a HD catback which later the HD muffler was replaced.Spent plenty on the system.Maybe someone builds a big Y pipe for the 1/2ton 5.3

 

long tube headers would be nice. not absolutley needed but you would get a nice gain from them. people have seen 20+hp from just a header swap and with a blower that gain SHOULD be even higher.

 

Congrats on the 6.0L!!!! You should have no trouble netting 400hp. Good luck.

 

Thats kinda what I had in mind. When the engine was getting installed I would take the old Y-pipe to a shop and fab a custom Y pipe with High flow cats. It sounds like the headers would be the biggest bang for the buck.

 

That would be a hellava muffler shop that could copy your old Y pipe with bigger tubing ,weld it up and have it fit.I would think they would need the truck there and custom fit it.Longtubes would be the best bang for the buck.A good used cams can be found for around $200,depending on the lift of the cam you could use new LS6 springs for about $90

 

my '03 is dual back to the muffler