2 questions. I'm an old guy with an old wife who doesn't like a lot of noise.
I have a 2003. It's stock with a 31/2" exhaust and stock muffler. Do you think the 4" would be worth the investment?
How much louder, I know it's difficult to quantify that, is your exhaust?
Does the cool hose add much compartment noise?
I tow a heavy 5th wheel whichs adds significantly to the db level.
Thanks,
Bill
In order for the 4" exhaust to be of any benefit over the 3 1/2", you also have to change the cast elbow off the back of the turbo, then you can go with a 4" down pipe also. Your stock cast elbow on your 03 goes from 4" off the turbo , to 3 1/2" to the downpipe.
You can find used cast elbows, I actually went that route, but until I installed a larger turbo, the results were not worth the effort.
The Cool hose is a nice upgrade, thick silicone, no baffles, I did not notice any noise increase until I pulled out the silencer ring from the inlet of the turbo, then it whistled quite a bit over stock.
Really, in all honesty, if your 03 is stock, changing your intake and exhaust will only net you cooler egt's, if you retain a closed airbox like the Icebox(closed to engine temps). I do not believe you will notice any mileage gains, if so they will be minimal, you may gain some hp & tq by removing the restictions in both intake and exhaust, but they will also be slight.
Just my . 02
