Exhaust Pressure

[89Suburban]

Has anybody ever really taken a reading of exhaust pressure at the EGR valve or head or exhaust manifold? Just curious.

 

[89Suburban]

Yap.


RETRO MODS ARE THE **** - HR STEPS IN DOG **** - OLD77 CAN'T SELL SHIRTS FOR **** - 89S SMELLS LIKE ****

 

[chengny]

At rated idle RPM, manifold pressure on these trucks (as designed- a SBC with heavy duty emissions/no cats and a dual 2 1/2" pipe OEM exhaust system, is actually negative.

I've never hooked up a vacuum gauge to see how low the pressure is; but if the A.I.R. pumps have their belts off, it is low enough to cause them to roll over in the direction that they would if the belts were on.

 

[89Suburban]

How is that possible?


Posted while on the porcelain throne

 

[Jims86]

How is that possible?


Posted while on the porcelain throne

If the pipe length is tuned correctly, the exhaust pulse from the previouse exhausted cylinder will create a slight vacuum behind it as it travels through the system....scavening baby!

 

[Jims86]

BTW, a walker quiet flow on a small lycoming 4cyl aircraft engine was between 0.04–1.2 psi.

 

[89Suburban]

If the pipe length is tuned correctly, the exhaust pulse from the previouse exhausted cylinder will create a slight vacuum behind it as it travels through the system....scavening baby!

Got ya.