Hello to make a long story short I bought a cali truck and I live in Texas. My truck is much quieter than my friends 5.3L and we both have the exact same original 40 series setup. My question is. Does anyone know how to remove the california emmisions equipment, and if it can be done would I need to get a tune for the pcm to adjust itself? Any help is appreciated because like I said my truck is really quiet and doesnt sound very aggressive at all

 

What are you planning to remove? Unless he removed that cats he should have them too.

 

ok well maybe Im mistaken in my assumption that is was the California stuff making my truck quieter. Here is the situation. I own a 2000 silverado ext cab LT 5.3L with a single in dual out 40 series. MY friend has a 2001 silverado z71 5.3L with a single in dual out 40 series. We both live in texas but my truck was bought in california and his in texas. His truck( and many other chevy's) are louder than my truck. I also have a k&N full intake as well so if anything it should be louder than his. Can anyone explain this to me

 

Is the exhaust piping the same size and does it exit the same location. I know when I had turn downs with my flowmaster, it was extremely louder than when exiting straight out the rear. Do both trucks have cats?

 

How long has he had his exhaust and how long have you had it. In my experience my exhaust has gotten louder after more miles I guess do to the expansion and contraction from the heat of the exhaust my racing bullets werent that loud till after 3 or 4 thousand miles then they sounded alot better to me. Your cats could also be clogged. How many miles does he have and how many do you have. Are the exhaust exits the same. Dumped or exiting out the back for both?

 

The California emissions are in the tune, that's why there is no longer a charge for CA emissions anymore. The only thing that might be added is an air pump which is electric, so you won't have any parisitic accessory loss. Pipe size and exhuast tips will make a difference. Plus maybe you don't have any holes in your exhaust system like your buddy might.

 

maybe that is something I neglected. My exhaust exits on the passenger side before the wheel. His exits striaght back. Im almost possitive that both of ours are 2.5" but Im not possitive would his be louder or quieter if he had 2.25" pipes?
If thats the reason, why would it be this way when my tips are closer to the muffler than my friends? Sorry for my ignorance but I would like to get this cleared up so my flows dont sound like gibsons anymore

 

There is little difference in the factory set up (if any) of a Cali truck or a non-Cali truck. Your trucks are NOT identical therefor it is reasonable to assume that they will NOT sound the same.

Most vehicles made today are fifty state legal from the factory, meaning that there is nothing special on a Cali vehicle.

 

well yes that is a given but im not talking about just my friends truck, compared to every other 5.3L ive heard with a 40 series mine is the most quiet. I just order some magnaflow cats and true dual bullets so help fix it hopefully but I would like to know why my truck is so much more quiet than other trucks

 

I think I remeber seeing you had the AIR setup on your truck at the Canyon meet. (This be NIkolai ) That could be something but I doubt it. Removing that would free up some weight and clean up the engine bay but not much more I think. Exhaust harmonics are very complicated, longer pipes versus shorter ones will make all the difference.