Join Date: Sep 2002
Location: Brisbane, Australia
Well, going by my days working in a smelter, the aluminized exhaust will just put an outside coating. This will stop the OUTSIDE elements from attacking the piping with rust. However, the insides are not protected, even if they are coated, due to the heat of the exhaust. It will have a 5 year bench life on a car.
When you talking about 14 gauge piping, your talking about the thickness of the pipe. The thicker, the more the pipe will "resonate" and give it a more deeper drone, especially if you get one of those rounded tips that point back inside the exhaust. However, the thicker the pipe, the heaver it'll be, and more strain will be put on your mounting brackets and rubber supports.
Try and push him for mandrel pending over the rear, it doesn't sound like much, but to get the flow out of the system, it'll work great. Mandrel bending the extractors/headers to the muff really doesn't do jack squat. It'll never hurt to ask if you can get a better deal.
You can always try a different exhaust shop!
"Keep it Real"
"Big D" Dion.
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