Dual Exhaust on 5.3L 05 Envoy XL??

[05gmcenvoy]

Hello, I'm new here and don't know anything about exhaust systems. Couple questions regarding Dual Exhaust on a 5.3L 05 Envoy XL.

1. I don't care about sound,but want more power, mileage.
2. Are there any that increase performance, if so what brand/model?
3. I am not a do it yourselfer, so how much should it cost me for install?

Thanks.

[ltdakheel]

do you have headers ??
if NOT start with it

check AMERICAN RACING HEADERS OR KOOKS HEADERS , LONG TUBE WITH y PIPE (catted or catless) , after that you can go for CORA TUORING OR SPORT CAR BACK . Or MAGNA FLOW DUAL CAT BACK SYSTEM ,
AND yes yes if tune with these systems , you must have 40 hp + with tune if you have CAI

kooks tbss will fits our envoy denalies also the ARH i talked to them my self

goodluck
omar

[JOETENO2]

Personally, I have duals from behind the cats on both sides all the way to the back. I plan on using the shorty headers which I have recently puchased. My system is 2 1/2" pipe all the way to the back with 3" stainless mufflers on both sides. The sound is great with a little drone at low speed in overdrive which mkes it sound mean! My only problem was finding a muffler shop willing to run my exhaust my way. I have only averaged 14mph city without a tune on uncallibrated 22" tires. I have a ecu tuned for my duals and headers along with my electric fan setup but I can't install yet as I haven't installed the fan yet. I want to install an all aluminum radiator first.

[blkenvoyon22z]

Check with big ed...hes running duals on a 04 slt xl 5.3 he can answer your questions

[bstromback2002]

I'm not sure on the mileage or any of that stuff cause that not what i was concerned with but your not going to get that much by just replacing your muffler you might get .5 mpg better but boy does it sound way better. Your going to be better off starting with headers and workin you way back if you want better mileage and more power but with header you should be carefull with what you go with you may loose some low end power if the primaries are to big, but i could be wrong the stock manifolds look so restrictive anything maybe a improvement. someone with a little more knowledge and experience can probably comment on that subject a little more i'm kinda curious myself.