Kevin McNulty
Former Editor, Mud Life
Nothing's quite as cool as the throaty growl of a high-performance exhaust system on hot rods, muscle cars, and race vehicles. And the good news is that squeezing engine performance out of your daily driver, 4x4, or trail rig doesn't mean you have to deal with a tooth-rattling, eardrum-bustin' exhaust drone inside the cab of your rig. Dynomax's new VT Muffler offers all the performance of a high-flow muffler without the nerve-racking exhaust drone some mufflers emit. The VT is designed to redirect the exhaust flow inside the muffler at cruising speeds to reduce drone, but when the hammer is dropped on the throttle it opens up and delivers on-demand performance.
The Dynomax VT is high-flow, straight-through stainless steel muffler designed to control exhaust drone with a valve that redirects flow. The calibrated internal valve redirects exhaust flow at cruising speeds, eliminating drone. The valve automatically opens and adjusts when accelerating for maximum flow. We are told the valve will not decrease performance, and we didn't notice any loss on our rig.
We replaced another brand of performance muffler with the VT muffler on one of our daily driver 4x4s and noticed an impressive drop in exhaust drone over the old muffler. Now long hauls on the highway are much more pleasant, yet we still have the power we need.
We needed an exhaust upgrade on our on-and off-highway trail rig. Not only was the muffler held in place with bailing wire (trail fix), but the performance exhaust drone of the old system was just too much. We recorded a decibel level of 104 dB at full throttle and 92 dB at 65 mph. This made it difficult to have a conversation or even think on long drives. A power lawn mower emits 107 dB!
Our old muffler and the new VT muffler's inlets and outlets were on opposite sides, so we needed to reconstruct the tailpipe. Dynomax also sells quality exhaust pipe, which can easily be cut and welded together.
Another hot tip: Use quality hangers that will flex with the body and frame of the vehicle. We broke at the least five of the cheapo exhaust hangers purchased at the local auto parts store. After the installation of the Dynomax VT muffler our decibel meter recorded a full-throttle level of 92 dB and a cruising level at 65 mph of 86 dB. This was a noticeable decrease of cabin drone inside the Jeep.
We highly recommend welding the exhaust system in on any vehicle used off road. Some of the connections on our old system weren't welded together, and we continually had to push and reclamp the pipe back together after each trail run.
