Dual Exhaust

[ChinoCharles]

Originally Posted by Doc Zaius

On the subject of backpressure, here's a real interesting link that I found while digging around on the 'net during ChinoCharles' Megan header dyno stuff. Explains why a less restrictive header/exhaust component seems to decrease lower-RPM power. Guess what?? Its NOT backpressure!!

Exhaust: The straight scoop on backpressure <-- awesome! must read!
Exhaust system backpressure <-- another good one.

At the end of the "must read" he says...

"So the loss in torque has nothing to do with backpressure and everything to do with gas velocity."

That statement made me laugh. Gas pressure and gas velocity are codependent. Although he does a great job explaining scavenging, I'd take it with a grain of salt. He left out the simple high school physics. It is still a good read though. I just don't think its all scavenging, just like I don't think its all backpressure. It is a combination of these and many more factors that determines the efficiency of an exhaust system.

[Black Yaris]

Originally Posted by ChinoCharles

At the end of the "must read" he says...

"So the loss in torque has nothing to do with backpressure and everything to do with gas velocity."

That statement made me laugh. Gas pressure and gas velocity are codependent. Although he does a great job explaining scavenging, I'd take it with a grain of salt. He left out the simple high school physics. It is still a good read though. I just don't think its all scavenging, just like I don't think its all backpressure. It is a combination of these and many more factors that determines the efficiency of an exhaust system.

I will would love to see a set of zoomies set up with your ITB idea

[Yaris Revenge]

I say slap 4 independent pipes on that sucker! A separate header for each cylinder! With 4 giant cans hangin' out the back! Hell yeah!

~YR

[Black Yaris]

Originally Posted by Yaris Revenge

I say slap 4 independent pipes on that sucker! A separate header for each cylinder! With 4 giant cans hangin' out the back! Hell yeah!

~YR

Why not it would match perfect with Chino's ITB idea he has been lookin into

[eTiMaGo]

but instead of having the pipes exit at the back, split them, two a side, right behind the front wheels. Then screw up your fuel map to make it extra rich, and spit FIRE!

[Black Yaris]

A fire breathing Egg!!
someone PLEASE photoshop that!!

[Sabretooth]

FlameYaris...why photoshop when theres youtube...


http://youtube.com/watch?v=2HxvS8knQJs

[heylookitsjames]

It seems to me that due to laminar flow, two smaller pipes with the same cross sectional area as one larger pipe would infact have higher gas velocity (this can be seen when solving the Reynold's Number equation for mean velocity and using an Re of 2300 it can be seen that L, or "characteristic Length"... in this case, the diatmeter of the pipe, will result in an smaller laminar flow value). Also, if they were fused/jointed correctly, they could be as uinrestrictive as well. In addition, scavenging effect (effectively having a wave of low pressure interlope its way back into the combustion chamber that aides the successive induction charge) is more pronounced on smaller diameter pipes...

/This being said, I think that twin exhaust would look kinda dirty...

[Doc Zaius]

Originally Posted by heylookitsjames

It seems to me that due to laminar flow, two smaller pipes with the same cross sectional area as one larger pipe would infact have higher gas velocity (this can be seen when solving the Reynold's Number equation for mean velocity and using an Re of 2300 it can be seen that L, or "characteristic Length"... in this case, the diatmeter of the pipe, will result in an smaller laminar flow value). Also, if they were fused/jointed correctly, they could be as uinrestrictive as well. In addition, scavenging effect (effectively having a wave of low pressure interlope its way back into the combustion chamber that aides the successive induction charge) is more pronounced on smaller diameter pipes...

Holy hell! Fluid mechanics? Must be an engineer!

[sf180th]

Originally Posted by heylookitsjames

It seems to me that due to laminar flow, two smaller pipes with the same cross sectional area as one larger pipe would infact have higher gas velocity (this can be seen when solving the Reynold's Number equation for mean velocity and using an Re of 2300 it can be seen that L, or "characteristic Length"... in this case, the diatmeter of the pipe, will result in an smaller laminar flow value). Also, if they were fused/jointed correctly, they could be as uinrestrictive as well. In addition, scavenging effect (effectively having a wave of low pressure interlope its way back into the combustion chamber that aides the successive induction charge) is more pronounced on smaller diameter pipes...

/This being said, I think that twin exhaust would look kinda dirty...

[hasher22]

Originally Posted by Sabretooth

FlameYaris...why photoshop when theres youtube...


http://youtube.com/watch?v=2HxvS8knQJs

wow that looks and sounds shit...haha major fart can

[Sabretooth]

Actually Looks good, as for my vid I Posted, yea...

Flamethrowers on a Yaris, the ultimate Riceburner

[eTiMaGo]

while searching for pictures of flaming exhausts I found this abomination... exhaust spinner. I'm gonna have to jump off a tall building now, nice knowing you guys...

[Black Yaris]

Ridin Spinna's

[Nimble]

rice rice baby....ding ding ding da da ding ding...vanilla...rice rice baby

[Nutzoids]

Originally Posted by Nimble

rice rice baby....ding ding ding da da ding ding...vanilla...rice rice baby

Word to your Mother!

[Chris07LB]

Originally Posted by Nimble

rice rice baby....ding ding ding da da ding ding...vanilla...rice rice baby

"Alright STOP!....Calobrate and LISTEN...."

[Nutzoids]

<object width="425" height="350"><param name="movie" value="http://www.youtube.com/v/MxN_pbMOFk0"></param><param name="wmode" value="transparent"></param><embed src="http://www.youtube.com/v/MxN_pbMOFk0" type="application/x-shockwave-flash" wmode="transparent" width="425" height="350"></embed></object>

I love it!