Despite Hemmings staffers' initial excitement, the new Dynomax VT has nothing to do with Vermont; rather, it uses valve technology to silence dreaded exhaust drone without hindering performance.
There’s no shortage of options for performance mufflers today, particularly if you’re shopping for something to put on your V-8-powered American car or truck. Exhaust technology has come a long way in the past few decades, narrowing the gap of compromise between legal sound levels and maximum engine output. Unfortunately, some of the high-performance mufflers on the market have the potential to yield tones under part-throttle cruising that can drive cabin occupants nuts, a condition that’s come to be known as exhaust drone.
Drone seems to hinge on multiple factors, including exhaust system confirmation, engine specs, cruise RPM and so on, but Dynomax has recently introduced an interesting approach to quelling this maddening condition. The new muffler, the Dynomax VT, makes use of an internal valve that the company says will cancel drone at cruise speeds while allowing unimpeded flow under heavy throttle.
The cutaway illustrates the design, which, despite its oval case and offset inlet/outlet configuration, utilizes a straight-through-style path from end to end. The forward chamber makes use of Dynomax’s Continuous Roving Fiberglass technology to provide sound similar to the Dynomax Ultra Flo series of mufflers, while the rear chamber contains the spring-loaded valve that opens when exhaust pressure increases, yielding particularly high flow (Dynomax says bench testing showed 841 CFM) and an aggressive sound.
Dynomax is offering the fully welded, stainless steel VT in two configurations: a 14-inch case with side inlet/center outlet and a 16-inch case with side inlet/side outlet; either can be had with 2-1/4, 2-1/2 or 3-inch inlet/outlet diameters. There’s even a limited lifetime warranty, and, if you’re concerned whether or not the sound is right for you, Dynomax also offers an interesting 90-day Performance and Sound Guarantee that allows purchasers to try the mufflers and return them within the 90-day period for a full refund if not satisfied.
You can also listen to sound bites of most Dynomax mufflers (though the VT sample is not yet posted) on the company website at www.dynomax.com. We haven’t yet heard the VT mufflers firsthand, but we’re curious to know how well they perform, so any input from folks who bought them would be welcome.