I have a 1997 Ford F350 5.8 motor. A local exuast shop is telling me to stay away from true dual exuast because its cutting my power down. There saying to go with a simple dual outlet muffler. Is it true that true duals are bad? If so, what is a good loud sounding dual outlet flowmaster to put on it?

 

It's mostly unnecessary unless you have 400+hp engine, and can cause you to lose your bottom end. It's also tough to get true duals on these trucks because of the front tank that runs along the driver's side of the bed.

Good intake, shorty headers into a new y-pipe into a 3" collector all the way back would probably be your best bet. If you want the dual tip look just get a dual out muffler. I would keep in mind that you are OBDII so you will start getting Check Engine Lights if you don't figure out a way to keep the O2 sensors.

 

Your local exhaust shop is correct. On newer trucks, there is no real advantage power-wise in running "true duals". Most factory and aftermarket dual exhaust systems utilize a crossover. A crossover will aid in the scavenging of exhaust gases, helping to increase exhaust gas velocity and, in turn, your truck's performance. A crossover will also smooth out your exhaust note.

In terms of muffler choice, what sounds good will depend entirely on your personal sound preferences. If you would like help selecting a Flowmaster muffler that will meet your needs, give us a call at 707-544-4761.