I have a '14 GT 5.0 that has a 2.9L Whipple on it with Stainless Works long tubes. I've added catalytic converters and changed the exhaust to a Borla Touring system which I thought was supposed to be one of the quietest available. It's still too loud for me at WOT, even partial throttle. Does anyone know if I changed the headers to a set of BBK's, if it would quiet it down and take the poppy/raspiness out of it? I want the lowest deepest tone I can get.

 

The Borla Touring's are only a little bit louder than the factory mufflers 'unless' they have been 'gutted' or messed with in some way. If you know they haven't been modified in some way, then the factory mufflers might be your best bet

 

Ricky, David makes a good point. After consulting with a few high performance Mustang GT builders, it seems that the Ford engineers got this one right. The Generation 5 Ford GTs have a very proficient exhaust system from the factory. But, since you are "aspirated," a aftermarket exhaust system would be advantageous, with a proper tune. P.S., check this out. SKU #: S7224304 MBRP's Pro Series is the best performance exhaust system that money can buy. It is a series designed and built for the serious enthusiast who will settle for nothing less. This Axle Back kit will provide a rich, mellow exhaust note that you expect to hear from your Coyote! I have had no experience with this system, but have done business with MBRP, and was never disappointed. Please do some research before buying this, or any, product.

 

X pipe is on the raspy side, H pipe usually gives a deeper sound.
Stock GT500 mufflers are popular with the 5.0 crowd.
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