heres a thought

[Anaema]

adding a small venturi in the exhaust system of a vehicle. since a venturi makes an area of low pressure in a given stream of fluid(fluid being something that has the ability to flow, such as liquids and gases), and everyone knows that high pressure likes to go to low pressure areas(or at least they should) the effect would be like pulling the exhaust/intake fluids into this low pressure area.

one way i can think of this benifitting a turbocharged vehicle is that the low pressure beyond the turbo would promote the exhuast gases to move faster beyond the turbo. thereby spinning the turbo up to full speed faster and reducing the exhaust pressure before the turbo. increasing flow in the given exhaust system, and decresing the back pressure.

on a naturally asperated engine this would literally suck the exhaust out of the cylinder, reducing the work the engine has to do to push the exhaust gases out of the engine.

on the intake side, it would increase the speed of the air going into the cylinders, which means more air can get to into the cylinder and produce more HP.

of course, slightly bigger piping would have to be used to make sure the gas keeps its speed. because if it goes back to the same diapeter pipe, the pressure would make the venturi work in the opposite direction its supposed to. or not work at all, and it would just be another restriction in the given system.

 

[MaxPower]

Extractors have this venturi/scavenging effect at the collector. Venturi's in the exhaust stream are also comonly used as crankcase oil breathers on race cars.

 

[Anaema]

wow, i hadnt known that. but still, what about putting a venturi in the intake manifold?

 

[Zuffen]

People have been selling exactly what you refer to for 30 or more years.

I had a client once with them on the exhaust of his Jaguar XK120 and he swore they worked.

If you look into the air speeds involved the exhaust gas is moving faster than the outside air you are trying to use to create the venturi effect. You may well be using the exhaust gas to suck outside air into the cone you have fitted to the exhaust.

From what I have read they will work quite well at speeds in excess of 400mph!

I notived no manufacturer of cars fits them so I gues they figure they don't work or are not worth the cost of fitting.

 

[Zuffen]

People have been selling exactly what you refer to for 30 or more years.

I had a client once with them on the exhaust of his Jaguar XK120 and he swore they worked.

If you look into the air speeds involved the exhaust gas is moving faster than the outside air you are trying to use to create the venturi effect. You may well be using the exhaust gas to suck outside air into the cone you have fitted to the exhaust.

From what I have read they will work quite well at speeds in excess of 400mph!

I noticed no manufacturer of cars fits them so I guess they figure they don't work or are not worth the cost of fitting.