To the silver C43 driving on the I-15 in San Diego on 12/22 at 5:30 pm
12-26-2010, 10:49 PM
#29
MBWorld Fanatic!
Oh I understand the sound the M113 can produce, for fun when I had my secondary cats removed I fired her up with nothing but the primarys connected and she sounded like an american muscle car!!! If i didn't know any better I would of thought I had a big block V8 sitting under the hood of my C43. It was such a VICIOUS sound 
I would love to have this sound but am concerned about the possible power loss... Perhaps an expert (Marcus I am looking in your direction) can chime in here about the possibility of power loss when going to straight pipes.
I would love to have this sound but am concerned about the possible power loss... Perhaps an expert (Marcus I am looking in your direction) can chime in here about the possibility of power loss when going to straight pipes.As long as the cat replacement pipe is the same diameter as the pipe it connects to (in a perfect situation), there should not be a noticeable loss. Why should straight pipe cause any loss? Because *good* high flow catalytic converters heat the exhaust without creating low pressure zones. That's important because hot exhaust flows faster than cold exhaust (think about the four states of matter). If the cat is worn and/or a bad design, the straight pipe will perform better.
12-27-2010, 08:28 AM
#31
MBWorld Fanatic!
I'm no expert in exhaust design. That would take someone with a much better understanding of mechanical engineering and fluid flow. I do know a little about straight pipe though.
As long as the cat replacement pipe is the same diameter as the pipe it connects to (in a perfect situation), there should not be a noticeable loss. Why should straight pipe cause any loss? Because *good* high flow catalytic converters heat the exhaust without creating low pressure zones. That's important because hot exhaust flows faster than cold exhaust (think about the four states of matter). If the cat is worn and/or a bad design, the straight pipe will perform better.
As long as the cat replacement pipe is the same diameter as the pipe it connects to (in a perfect situation), there should not be a noticeable loss. Why should straight pipe cause any loss? Because *good* high flow catalytic converters heat the exhaust without creating low pressure zones. That's important because hot exhaust flows faster than cold exhaust (think about the four states of matter). If the cat is worn and/or a bad design, the straight pipe will perform better.
12-28-2010, 11:38 AM
#33
MBWorld Fanatic!
It improves scavenging. In an exhaust, you want velocity. Exhaust pulses that bounce around (the reason why bigger tubing is not necessarily better) don’t exit as quickly as they could if they left in an orderly fashion. One reason they bounce around is because of the uneven nature they are released (V12’s are smoother than 8s, which are smoother than 6s, which are smoother than 4s, 2s, and thumpers are a mess). An x-pipe forces the exhaust banks to intersect, smoothing out the flow. Think of it as two little streams. The speed of the water increases as the water intersects. The only difference is the exhaust has two exits.
