MBH Tri-Y scavenging effect video
#28
6000-7000 rpm these headers sound sweet Down shifting is growling and mean. No cats plus Renntech Mufflers I know you're lov'in the tone. A cold start is like a Lion's roar
#29
Super Moderator Alumni
Joined: Dec 2009
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From: USA
2011 GLK 350, 2013 GT-R, & 2013 RAM 1500
#30
#31
MBWorld Fanatic!
Joined: Apr 2006
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From: Central New Jersey
CLK63 Black, E350 Wagon, Supercharged Denali, Lotus Elise, Tesla Model 3 Dual-Motor.
#32
#35
good explanation
No offense but I think the video and it's relationship to "exhaust scavenging effect" is a bit misleading. My understanding is that header primary tube diameter, and more important, primary length are tuned to a specific RPM. Pulses are created in the primary tube by the opening and closing of the exhaust valve. A negative pressure wave naturally develops after an exhaust charge leaves the primary. The science and art of header engineering is to adjust header length so that the negative pressure wave reaches the exhaust valve at the optimum working rpm. That is what creates "exhaust scavenging effect". It does no good to tune headers for 7000 rpm if the engine spends most of it's working life well below. "Long tube" headers work so well on the street because the maximum "exhaust scavenging effect" takes place in the middle of the engine working RPM. This creates a much better torque curve, which is very desirable in a street application, verses a race engine requirement of maximum horsepower with little regard for mid-range torque. Simply blowing air in a tube does create vacuum, known as the venturi effect. Every carburetor and perfume sprayer uses that principle. Tuning negative pressure waves in the exhaust primary tube is what creates exhaust scavenging. Hopefully your long tube headers were designed using the scientific formulas available and then fine tuned on the dyno for a specific torque range. If so, I'm sure they are winners!
#36
That looks a lot nicer than a pic I saw of the flanges from another competing company that also begins with the letter M.
Hooley: Are you going to post pics of the headers with CATS or is bhamg?
Hooley: Are you going to post pics of the headers with CATS or is bhamg?
Last edited by Sincity; 06-17-2010 at 04:32 PM.
#37
Vegas_AMG and myself just came back from hearing bhamg's car. His car sounds simply ferocious and makes mine feel like a Tercel. Also had a surprise visit from C63_Guy. Great seeing all you guys again.
Good job to MBH and Hooley.
Good job to MBH and Hooley.
#38
#39
Thread Starter
Former Vendor of MBWorld
Joined: May 2009
Posts: 2,305
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From: Valley of the Sun, Arizona
C63, SL55, E55, CLS55, ML63, C55
Thanks alot guys. The kind words really mean a lot to me. Honestly I couldn't believe how mean the car sounds with 4 cats and the resonators.
#43
Didn't really take many...I probably should have but didn't...just must have been doing other things. That said, from my iPhone here are the test pipes and also the OE cats and California-legal replacement cats. Imagine the new primary cats in place of the test pipe and you have it. At the end it was very exciting to see it all get bolted up...so clean, so slick...I cannot say enough good things about how Richard Garcia and Dyno-Comp handled the fabrication, installation and tuning. Not techs but amazing craftspeople...
#44