Is it a silly question?

[general patten]

Can u have a square exhaust or does it have to been round tube.....reason I'm asking this is because I want too lower my car as max as possible with out putting airbags on it?

 

[dozypillock]

Can u have a square exhaust or does it have to been round tube.....reason I'm asking this is because I want too lower my car as max as possible with out putting airbags on it?

I can see no physical reason why not, although exhaust gas flow may be affected?
I cannot see how you would save that much on height either as is would still need similar volume, to work efficiently.
You would probably have to go more rectangular, and flatter, to gain much height?

Neil

 

[def90cars]

Don't show this to Lee63, he'll be wanting some.

 

[wongl]

From a noise suppression point of view, the exhaust pipe can be round, square or rectangular - it is the change in effective cross-section area (which causes a change in the acoustic impedance) that causes the sound to be reflected back 'up stream'. While the cross section shape of the pipe will affect the airflow, if nothing else the surface area would be different, I would imagine that it will not affect the airflow all that much.

A bigger challenge would be for the catalytic converter and/or DPF as changing the shape of these would be £££.

 

[Sp!ke]

Don't show this to Lee63, he'll be wanting some.

Some good up-cycling of old table legs there.

 

[general patten]

Cool thanks for the replys

 

[Bellow]

It's not a great idea - especially on a NA engine.
To get the same flow you need to increase the cross-sectional area. Changes in cross-sectional area create pulse wave reversals (as in a 2-stroke expansion chamber). That's without factoring in the turbulent in-pipe flow caused by the disparity in flow velocity at the pipe's centre compared to the 'corners' where it will be slow due to wall friction.