Stock muffler: ~19 pounds
Exhale AB: ~6 pounds

Why is this significant? Because when you are looking at areas to reduce weight on the car to improve handling, as a rule, you want to drop weight above the car's beltline (make it more bottom heavy) and the extreme ends of the car i.e. forward of the front axle and behind the rear axle to improve the car's ability to rotate and transition on steering input (for the physics behind this, visualize a figure skater with her arms extended vs. one with her arms drawn in).

The Exhale AB represents an important step in targeted weight reduction on the Evo, and WORKS' decision to go mufflerless was based not only on the philosophy that running no muffler will outflow a muffler every time, but also that eliminating the muffler canister is a significant point of weight savings on the car.

-- DavidV

 

Can we hear a sound clip?

Also, do you have any cross-section pictures of the stock muffler?

 

here's the inside of the stock evo muffler...

 

Any updates as to when the Exhale will be ready for shipping?

 

I'm sorry, but I can't seem to follow the flow of the black arrows? I can't tell what chambers are connected and how?

 

All I know is that it is the diagram out of the factory manual. Bottom line is that it looks restrictive...probably the most restictive part of the whole exhaust system. Which is why I am guessing Works chose to tackle only that part of the exhaust system first.

 

and save 13lbs. at the same time

 

When the exhaust isn't flowing a lot, the backpressure valve is closed, making the exhaust flow along the red line (the dotted section goes under (actually around) the center can in the muffler, through the section which I colored yellow. When you are hard on the throttle, it opens the backpressure valve and flosw through the section that I colored blue along the green arrow. Although the stock system is good for reducing idle and low throttle volume, it is also heavy because it is so large and has so many internal components.

I hope this helps.

Josh