Dump Valve ___ please help

[stevenrsturbo]

I know dump valve are for turbos only ????
or are they
i know of 4 people now who claim to have dump valves on thier cooper s works
i want one
can i get one
any one please help ?!!!!!!!!!!!!!!!!!!!!!!
where can i get one ???????????????

[Mugami]

If what your refering to is a blow off valve or by pass.. yes the MCS has one!! works or not.. we all do.

Now for my opinion why we dont get that great Whoosh sound when we let off the gas. unlike a turbo car.
a turbo is placed before the TB. there for the inlet are is still allowed to free flow into the compressor and is being compressed between the turbo and the TB and must be released via the blow off valve to keep from breaking seals and such. Giving the great whoosh from the excess pressure.

Our SC cars a different due to the fact the SC is after the TB and not before it. When you chop the throttle on the SC this cuts off the incoming air to the SC. with no air coming in to compress then theres no compressed air to go whooshing out of the Bypass/blow off valve when it opens via the command of the TB.

This same bypass valve is under current review as being the cause of the surging or yo-yo effect with the MCS.

[obehave]

Straight from Eaton:
The Eaton supercharger system incorporates a specially designed bypass valve, which is actuated by a vacuum motor near the throttle body, and recirculates the supercharger air flow when boost is not required. During typical driving conditions, the engine is under boost around 5% of the time, which means the remaining 95% of the time the engine is under vacuum, allowing for better fuel economy and a quieter ride. In addition, the helix angled rotors, along with specially designed inlet and outlet port geometry, also reduce pressure variations resulting in a smooth discharge flow and a lower level of noise during operation. The associated ducting and mounting used in installing the supercharger can play a major role in reducing the noise emitted by the supercharger.

Link to the whole article. Very good reading.

A blow off on an S is just stupid.

[Mugami]

Leave it to Obehave to pull out the tech. Stuff on the subject. For me i just try and make it sound believable. Which in half the time im right. the other half im close enough for goverment work. then theres the other 10 percent im so full of it.. its not even funny anymore. yes i try and give 110 percent all the time. so dont bug me on the math.

Good work as always Obehave and yes it was good reading.

[Windshadow]

Quote: Originally Posted by obehave

Straight from Eaton:
The Eaton supercharger system incorporates a specially designed bypass valve, which is actuated by a vacuum motor near the throttle body, and recirculates the supercharger air flow when boost is not required. During typical driving conditions, the engine is under boost around 5% of the time, which means the remaining 95% of the time the engine is under vacuum, allowing for better fuel economy and a quieter ride. In addition, the helix angled rotors, along with specially designed inlet and outlet port geometry, also reduce pressure variations resulting in a smooth discharge flow and a lower level of noise during operation. The associated ducting and mounting used in installing the supercharger can play a major role in reducing the noise emitted by the supercharger.

Link to the whole article. Very good reading.

A blow off on an S is just stupid.

realy good stuff
How exactly is the MCW unit diferen from the standard S unit from the photos they both look like the The Eaton Supercharger Model 45 or is it the longer model 62?

[obehave]

From what I remember the JCW is the same M 45 unit. Cleaned up and with ceramic coated blades.
Some of the real tech guys here know the specifics better.

And thanks Tony

[kapps]

The model used is most likely the M 45. If you go into the aftermarket suppliers, the M 45 is meant for 1.0-2.4 liter engines. The other models are for bigger engines. One thing I really find interesting is how the "bypass" allows for better economy when it's not being used.

[Ricco]

Quote: Originally Posted by Mugami

Our SC cars a different due to the fact the SC is after the TB and not before it

Is that a feature of all supercharged cars or specific to only the MCS?

Cheers,
Richard.