Not as hard as it is to make race winning power with manifolds.
Seriously, I had dumps and a good sized cam on my 5.9 with headers, X-pipe and super turbos, and its hard to hear my car in a video where I'm going down the track against a stock Pontiac G8.
I went to Ultraflow welded mufflers because it was too quiet, and I have to worry about pissing people off at the golf course-LOL.
With tailpipes, X-pipe and super turbos (and if you want to get crazy some glasspacks between the X and mufflers) you could make pretty much anything quiet. Then get some electric cut outs for when you're actually racing. Imagine the look on dude's face when you open that up halfway through 1st gear. LOL
If you're going to build a real street sleeper that can knock people out, I highly recommend a good deal of hidden nitrous and a good controller to enable traction. Big sleds have lots of places to hide a bottle or two!
its Chevrolet, but you get the idea. Probably wouldn't work on Big Block Mopar though. LOL.
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