[flattusmaximus78]

Originally Posted by flowmann Ryanw - Thanks for your questions and we're glad you love your Super 10's! Just so we're on the same page, when we're talking about chambered mufflers, we're referring to chambered Flowmaster mufflers. We don't want anyone to think we're talking about other mufflers with a bunch of compartments and mazes for the exhaust gases to traverse in order to get out the other end. The Flowmaster mufflers have different free-flowing chambers in succession from one end to the other. The only chamber in our mufflers people may confuse with a restriction is in our popular 3 chamber mufflers. They have a Resonant Tuning Chamber, which cancels out unwanted sound. This chamber doesn't exit in the single and two-chamber mufflers. A 3-Chambered muffler Straight-through mufflers only interupt flow of exhaust and create turbulence of the exhaust gases in order to shed off sound by trapping it in the insulation. The internal design (see the chevron shapped baffles) of our chambered muffler is designed to work with exhaust pulses to promote velocity and pull the gases through the muffler so the can get out of the exhaust system faster. We're not sure about the test's your referring to, but it's possible the other mufflers aren't doing the same job our chambered mufflers are doing for the application tested. Every exhaust system has drone and every exhaust system is different. It's sound that comes from the exhaust valves opening and closing creating pulses and waves the exhaust system. Some people are more in tune with the sound than others. If we fixed drone on one car with specific changes to the mufflers, we'd have to start over with the next. When designing and building bolt-in systems for newer car, it's much easier to tune out drone, or at least find the happy medium between tone and volume while improving power. We don't release a Cat-Back or an Axle-Back system unless we've proven that it increases power by making dyno pulls before and after installation.

Flomaster is such fail stuff omgzzzzz

[flowmann]

Originally Posted by fogged306 Because backpressure means that there's not a suction effect going on at the cylinder during the exhaust stroke. This can result in not all the exhaust gases leaving the cylinder during the cycle and contaminating the next intake charge, and it means that even with a cam with positive overlap, you're not taking advantage of scavenging, which if done right can actually draw some intake charge in on top of what the intake stroke of the piston can draw in. This means that you can cram more air in the combustion chamber than you would without a proper exhaust system.

Fogged306 is right. Back pressure can cause “exhaust reversion”. This is when spent exhaust gases in the exhaust can actually back up into the combustion chamber during valve overlap phasing of the camshaft. Scavenging done by header and muffler design with zero back pressure is the way to make optimum power.

[69fastback]

Back to the original topic at hand. I had a full custom exhaust built on my car for $150 yesterday. That was using my mufflers, and X-pipe, but he had to run all new 3" pipe. He did an awesome job on it.

[69fastback]

Not bad work for $150...


He still hadn't welded the turndowns on on these pics, but you can see he did a nice job.

[Tonifreakshow]

Would a NON mandrel bent 3 1\2 exhaust that necks down to say 2 1\2 at the bends be equal to a mandrel bent 2 1\2 system but only louder? I'm asking because I read that an exhaust system flows as good as the smallest diameter in the system.