Roush M90 interesting mod

[Makdaddy]

OP

Are you running a boost gauge?
Did you see any level change?

Sorry saw the vid
You stated more stable boost but did you see any gain at all?

 

[klaw]

No it isn't, none of the Eaton Roots blowers are compressors, they simply move air.

The only point of "moving air" is to pack more into the intake manifold than can get there otherwise. If the manifold goes into positive pressure (boost) there is air compression taking place.

 

[05armygt]

The M90 is a compressor.

You are wrong....the compression takes place in the manifold. The m90 just accelerates air...basically a big hair dryer

 

[05armygt]

The only point of "moving air" is to pack more into the intake manifold than can get there otherwise. If the manifold goes into positive pressure (boost) there is air compression taking place.

The air is compressed in the manifold, the m90 does not compress the air, it simply forces more air into a tight space where it compresses...NO COMPRESSION takes place in the rotors...

 

[05armygt]

OP

Are you running a boost gauge?
Did you see any level change?

Sorry saw the vid
You stated more stable boost but did you see any gain at all?

Yes, looks like .5 to 1 psi change at WOT but the boost kicks in much earlier now. Dyno is this week so we will see

 

[klaw]

The air is compressed in the manifold, the m90 does not compress the air, it simply forces more air into a tight space where it compresses...NO COMPRESSION takes place in the rotors...

The action of the rotors causes the compression - that's what compressors do. I have a degree in Mechanical Engineering and work in the oil patch with compressors all fucking day long. The air doesn't just magically compress into that tight space by itself.

 

[05armygt]

The action of the rotors causes the compression - that's what compressors do. I have a degree in Mechanical Engineering and work in the oil patch with compressors all fucking day long. The air doesn't just magically compress into that tight space by itself.

A: All Eaton superchargers use the roots type supercharging principle. The roots supercharger is a positive displacement pump that moves air in pockets from the inlet to the outlet of the supercharger with no internal compression. The supercharger creates “boost” by moving more air into the intake manifold than the engine is utilizing, thus creating higher than atmospheric pressures in the intake manifold. When boost is not desired on an Eaton roots supercharger, the bypass valve allows the supercharger to spin with negligible parasitic loss as there is no internal compression. The Eaton roots supercharger uses 3 lobe (“M”) or 4 lobe (“TVS-R”) meshing rotors that are similar (but reversed) in geometry. The rotors operate at a 1:1 speed ratio.

There you go man directly from eatons site...the blower is not a compressor so hop off your mechanical degree high horse

 

[JeremyH]

I think yall are just getting picky on the wording. We know the rotors dont physicaly compress the air in a postive displacement "roots" blower like the rotors in a twin screw do. However, from a mechanical and physics standpoint the eaton m90 is still an air pump which is a mechanical device used to compress/pressurize the air ouput and would be considered an air compressor even though the act of compression isn't physical happening in the rotor pockets as it spins. A turbo or centri blower's turbine inducer and exducer dont physcialy compress the air between the blades either, they are also air pumps and they accelerate the air. They are still called "compressors" none the less and thats the ultimate goal of the device. Technicaly it is an air pump used to move and pressurize air, which by definition is an air compressor regardless of the method used they achieve the same goal.

Didn't intend to stir up such a heated debate by refering to a roots blower as an air compressor.... lol

 

[Makdaddy]

 

[05armygt]

I think yall are just getting picky on the wording. We know the rotors dont physicaly compress the air in a postive displacement "roots" blower like the rotors in a twin screw do. However, from a mechanical and physics standpoint the eaton m90 is still an air pump which is a mechanical device used to compress/pressurize the air ouput and would be considered an air compressor even though the act of compression isn't physical happening in the rotor pockets as it spins. A turbo or centri blower's turbine inducer and exducer dont physcialy compress the air between the blades either, they are also air pumps and they accelerate the air. They are still called "compressors" none the less and thats the ultimate goal of the device. Technicaly it is an air pump used to move and pressurize air, which by definition is an air compressor regardless of the method used they achieve the same goal.

Didn't intend to stir up such a heated debate by refering to a roots blower as an air compressor.... lol

Look what you did!!!! Just look at it!!! No the entire time I was just trying to show the the compression of air does not take place in the rotors... Which is essentially a compressor. However though...eaton trumps all which is why I just went to the horses mouth...they say it's not one..so I'm going with them haha but yes, from mechanical standpoint.. The basics of what it does you can call it that

 

[908ssp]

Actually pressure is a result of air forced into a restricted space. So it could be argued that the restriction creates the pressure without restriction there is only air moving no pressure. The nice thing about the improved roots because it does not restrict the air in the rotors it creates less heat with the bypass valve open than a screw blower since it restricts the air flow in the rotors before dumping the hot air into the manifold to be recirculated by the bypass valve to be heated again.

 

[JeremyH]

My bad lol

Its an air pump used to force air into a smaller space thus compressing it.

Obviously we dont bolt on blowers and turbo's to send the air to atmosphere and not compress it.

 

[05armygt]

Actually pressure is a result of air forced into a restricted space. So it could be argued that the restriction creates the pressure without restriction there is only air moving no pressure. The nice thing about the improved roots because it does not restrict the air in the rotors it creates less heat with the bypass valve open than a screw blower since it restricts the air flow in the rotors before dumping the hot air into the manifold to be recirculated by the bypass valve to be heated again.

Finally!!!!! Someone with the correct logic

 

[05armygt]

My bad lol

Its an air pump used to force air into a smaller space thus compressing it.

Obviously we dont bolt on blowers and turbo's to send the air to atmosphere and not compress it.

You sir, get a cookie for being right on the dot.

 

[8306gt]

My bad lol

Its an air pump used to force air into a smaller space thus compressing it.

Obviously we dont bolt on blowers and turbo's to send the air to atmosphere and not compress it.

The air still isn't compressed, just because there is more air than the engine would normally be able to take in. It is simply back pressure in the manifold which is not the same as compressed air.

 

[Cal26Stang]

Either way, I would probably not spend several thousand on an M90 that has probably hundreds or tens of thousands of dollars worth of research in it's development which included those ports and then change the design without knowing for sure it would overall benefit my car. It seems to me that those ports were included there for a reason, but I understand your logic and I can hear the difference in the videos. Very interesting thread

 

[klaw]

The air still isn't compressed, just because there is more air than the engine would normally be able to take in. It is simply back pressure in the manifold which is not the same as compressed air.

The air is compressed - that's how it's able to exert a higher pressure on the inside of the intake.

 

[05armygt]

Either way, I would probably not spend several thousand on an M90 that has probably hundreds or tens of thousands of dollars worth of research in it's development which included those ports and then change the design without knowing for sure it would overall benefit my car. It seems to me that those ports were included there for a reason, but I understand your logic and I can hear the difference in the videos. Very interesting thread

I could understand your conflict here, but I didn't just do this on a whim my friend, I talked to many roush and eaton reps prior to doing this and they all said their wouldn't be any negative side effects. The only thing I would gain is noise factor, the only reason to have them in the design is to meet noise pollution requirements, it bleeds back pressure to keep the air from slamming against roof of the housing (which is where you get the whine) trust me of it was a vital hole I wouldn't have even looked at it but plugging silencer ports has been done for ages.

 

[8306gt]

The air is compressed - that's how it's able to exert a higher pressure on the inside of the intake.

Just because a Roots supercharger moves more air than the engine can normally take in doesn't make the air compressed. A twin screw compressor, a centrifugal supercharger, and turbo's all compress air within themselves and then force that compressed air into the engine, a roots supercharger simply forces uncompressed air into the manifold. There simply is no compression of air in a Roots style supercharger system. These are not the same actions period. Engineer or not you aparently do not understand the principles of what you are saying.

 

[JeremyH]

Sigh... going to leave this one alone now, the ignorance is giving me a headache lol

Everyone knows it PureFuckingMagic then that compresses the air anyways...

Have to say this though, the turbo or centri's inducer and exducers in the wheel itself doesn't compress the air either it accelerates it like roots rotors do and forces it into a restrictive cover/housing which is what compresses the air, much like the lower intake manifold and engine do for a roots blower.