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NPP mod thought

5K views 5 replies 5 participants last post by  Ragtop 99 
#1 ·
So.. I have searched and searched, I know that most peaple do the mild2 wild switch, pull the fuse (which I have done already) or have done the "cut the muffler case open a bit and weld a stright pipe in " on NPP mufflers. I know about drilling a hole thru the case/inner pipes on stock mufflers and patching the outer hole . could that work on the inner pipe of the NPP ? and give it even more growl?
 
#2 ·
are you looking for louder sound or a different tone? A different catback will change the growl as opposed to just making it louder.

If it is not loud enough, I'd pull the catback off and put straight pipes with a resonator in. You can add header cones in the tips if ends up too loud for local noise ordinances.
 
#6 ·
Maybe I misunderstand your post. Headers are illegal in FL, so I'm not sure what you're trying to communicate if compliance with FL law is a central point of your post.

The SLP loudmouth exhaust for the F-body was a pipe with a simple resonator. No muffler of any sort. Plenty of people in FL ran them. That can be done on a vette too. Add race bullets or header cones if it is too loud.
 
#5 ·
I know about drilling a hole thru the case/inner pipes on stock mufflers and patching the outer hole . could that work on the inner pipe of the NPP ? and give it even more growl?
No, this wouldnt work. The inner pipe on the NPP aka the "straight pipe" section already has holes in it. This is what gets covered when people do the muffler mod. The holes are what make it still quiet even when the valve is open. If all you want is sound I highly suggest doing the muffler mod. It is really simple, cut open a section of the muffler, weld or clamp some metal tubing around the :straight through" pipe and reweld the meffler back together. This mod along with a mild to wild switch of choice is pretty fantastic. Gives the car a nice growl when you want it and comfy quiet stock sound when the wife is complaining. I have put my Z with this done next to a car with a really expensive Corsa cat back and the sound and volume are very ver similar.
 
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