Hummer H3 MagnaFlow Exhaust - Going With The FlowPosted in Project Vehicles on January 1, 2009
We've been quite happy with the power output of our Alpha's 5.3L V-8. This 300hp, 320-lb-ft engine has proven itself to be very well matched to the 4,854-pound H3. From daily commuting to towing trailers to powering over hilly trails, we've never wished for more power. But hey, we're always game for more, and that's why we bolted on a MagnaFlow Performance Exhaust after-cat system.
This stainless steel system, new for the H3 Alpha, increases the diameter of most of the exhaust tubing by 1/2 inch; offers a more consistent tubing diameter and less bends than the OEM exhaust; and features a dual split-rear exit design as opposed to the single exhaust tip of the stock system. Further, the MagnaFlow resonator and muffler are freer-flowing than the stock units they replace. Both units have a stainless steel perforated core, and the muffler has stainless steel wool-an acoustical absorbent material that has high heat resistance. There are no baffles, chambers, or louvers to impede flow.
Matt Dinelli at Attitude Performance installed our new MagnaFlow system quickly and it went together with no glitches. Here are the highlights of this simple, quick install.
The MagnaFlow system for the H3 Alpha has an MSRP of $733.66, which is in line with the pricing of other systems. We're impressed by the overall quality of the MagnaFlow system, and it's so well-built, it's a shame it's hidden under the truck. When we left Attitude Performance after the install, we were towing a 5x10 trailer loaded with the H3's factory wheels and tires, the stock exhaust, and other odds and ends. We could feel a power difference. The engine felt more responsive. No scientific data to trot out, just seat-of-the-pants feel. Around town at low speeds the system generates a nice exhaust burble that you can hear in the cabin. At highway speed the new system is audibly transparent. We haven't had the system installed long enough to generate hard numbers, but we're interested to see if fuel mileage numbers increase slightly due to the freer-flowing system. Overall, we're happy with the results so far.