You should know that they don't work together. You get one or the other. 
Dumped exhaust vs. cutout mpg
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Dumped exhaust vs. cutout mpg I know that a open cutout is worse mpg, but how much better do you think a bullet turndown on a y pipe mpg would get compared to cutout?
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From: Philly
IMO, exhaust is a sound mod first, performance mod second. Do whatever you think sounds better, then get your car tuned to optimize the effects.
An open cutout only hurts your fuel economy on a stock tune because it throws off the A/F ratio. If you get your car tuned with the cutout open, you'll gain mileage by making the exhaust work more efficiently.
IMO, exhaust is a sound mod first, performance mod second. Do whatever you think sounds better, then get your car tuned to optimize the effects.
IMO, exhaust is a sound mod first, performance mod second. Do whatever you think sounds better, then get your car tuned to optimize the effects.
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From: Vancouver,[KITSILANO].B.C. Canada *WestCoast*
An open cutout only hurts your fuel economy on a stock tune because it throws off the A/F ratio. If you get your car tuned with the cutout open, you'll gain mileage by making the exhaust work more efficiently.
IMO, exhaust is a sound mod first, performance mod second. Do whatever you think sounds better, then get your car tuned to optimize the effects.
IMO, exhaust is a sound mod first, performance mod second. Do whatever you think sounds better, then get your car tuned to optimize the effects.
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From: Philly
My cutout open dropped my fuel economy by 1 mpg. Explain to me how a more efficient exhaust setup will drop fuel economy? It's because it threw the tune off even more - rich down low, lean up top. Same as a set of headers or a catback with a freer flowing muffler than stock.
