Coating on supercharger blades
- Thread starter drewz313
- Start date
vsl67
New member
If your confident you can rebuild them have a read
http://www.grandprixforums.net/f18/i-rebuilt-my-m90-rotors-home-20356.html
http://www.grandprixforums.net/f18/i-rebuilt-my-m90-rotors-home-20356.html
TheOtherNick
The mod from over yonder
You send them off and have a company coat them.
Magnuson does coatings... and further more you can specify if you need a wet or dry coating...
Dry coatings won't stand up to methanol injection or something like a draw through carb setup (where the charger is wet with fuel) or a wet N2O kit spraying into the blower...
This is what most OEM chargers come coated with.
Wet coatings will handle the fuel, methanol, water, and nitrous...
Check the links in the comments here...
Dry coatings won't stand up to methanol injection or something like a draw through carb setup (where the charger is wet with fuel) or a wet N2O kit spraying into the blower...
This is what most OEM chargers come coated with.
Wet coatings will handle the fuel, methanol, water, and nitrous...
Check the links in the comments here...
minichopper6hp
Banned - Busted For Scamming
Too much. I could sell you a pair of recoated ones cheap. I would need a core back though.
No idea on the price, no... sorry... you'd have your best luck going to them directly.
It's called an 'abradeable teflon coating' and when i was reading up on that and googling it i ended up at many turbine blade repair, inspection, and coating business.
It seems like this is something that trickled down from aviation ... and so there aren't really that many places that you could get this done at... probably will cost a premium if it's not a large quantity batch process like it would be for OEM rotors or a turbine engine overhaul....
(Cliff notes: no idea)
It's called an 'abradeable teflon coating' and when i was reading up on that and googling it i ended up at many turbine blade repair, inspection, and coating business.
It seems like this is something that trickled down from aviation ... and so there aren't really that many places that you could get this done at... probably will cost a premium if it's not a large quantity batch process like it would be for OEM rotors or a turbine engine overhaul....
(Cliff notes: no idea)
minichopper6hp
Banned - Busted For Scamming
Its not teflon. Its abradable powder coat.
QUICKSILVER462
New member
Positive displacement supercharger modifications | Supercharger Performance and Engine Performance Parts
Rotor coating
One of the changes between the earlier and later generation Eaton superchargers is that the newer blowers have coated rotors. The rotors are coated with Teflon/Ceramic/Carbide abradeable coating. The coating does two things:
1- Helps the rotors withstand, distribute, and manage heat better especially when using the supercharger at higher rpms.
2- The coating adds thickness to the rotor. When the rotor is heated by its normal operation it expands to a certain extent. If the rotor expands too much within the housing then rather than having a proper seal against the housing wall (to trap air) it may touch the wall causing the whole assembly to catastrophically seize. To prevent this seizure, there is typically a tolerance (a room for error if you will) left between the rotor tip and the housing. This room is bad for performance because it allows the air to escape rather than be trapped by the rotating rotor and thus reduces the superchargers pumping and adiabatic efficiency. To improve efficiency on the later generation superchargers the Eaton engineers have come up with an abrade-able teflon-carbon based coating that makes the rotor slightly thicker. When the rotor expands it now basically touches the housing, but this is now not a metal on metal contact, but rather a metal (housing) to carbon-teflon (rotor coating) contact. What happens here is that the harder material (which is the aluminum housing) wears down the softer material (the carbon-teflon coating) shaping it to the exact shape of the housing and giving a more exact seal between the rotor tip and the housing, better trapping air, improving supercharger flow per rotation, reducing pumping losses, and thus reducing outlet air temperatures. This idea can be used on any twin rotor charger to improve rotor seal and is really a great engineering solution.
Rotor coating
One of the changes between the earlier and later generation Eaton superchargers is that the newer blowers have coated rotors. The rotors are coated with Teflon/Ceramic/Carbide abradeable coating. The coating does two things:
1- Helps the rotors withstand, distribute, and manage heat better especially when using the supercharger at higher rpms.
2- The coating adds thickness to the rotor. When the rotor is heated by its normal operation it expands to a certain extent. If the rotor expands too much within the housing then rather than having a proper seal against the housing wall (to trap air) it may touch the wall causing the whole assembly to catastrophically seize. To prevent this seizure, there is typically a tolerance (a room for error if you will) left between the rotor tip and the housing. This room is bad for performance because it allows the air to escape rather than be trapped by the rotating rotor and thus reduces the superchargers pumping and adiabatic efficiency. To improve efficiency on the later generation superchargers the Eaton engineers have come up with an abrade-able teflon-carbon based coating that makes the rotor slightly thicker. When the rotor expands it now basically touches the housing, but this is now not a metal on metal contact, but rather a metal (housing) to carbon-teflon (rotor coating) contact. What happens here is that the harder material (which is the aluminum housing) wears down the softer material (the carbon-teflon coating) shaping it to the exact shape of the housing and giving a more exact seal between the rotor tip and the housing, better trapping air, improving supercharger flow per rotation, reducing pumping losses, and thus reducing outlet air temperatures. This idea can be used on any twin rotor charger to improve rotor seal and is really a great engineering solution.
minichopper6hp
Banned - Busted For Scamming
Yea water meth or alky or whatever you inject doesnt effect it. The reason why the powdercoat comes off is because eaton did not do adequate prep to the rotors before coating.
GR8racingfool
New member
^ exactly.
The rotors were machined to tolerances, and then cleaned and then coated. The machining left too smooth of a surface, and the coating would not stick to it in many cases cause it had nothing to grab onto but its self. Kinda like when you paint something, you have to scuff up the surface as prep...same concept here. Running rich, lean, meth, N20 wet or dry does not directly harm the rotor coating. If its peeling after this is shot through it...then it was on its way to peel anyway.
They (Eaton) realized their mistake with Magnuson, and all their rebuilds they were doing. So when they redesigned the 3800 for 2004's new model, they redesigned the M90 as well. The case changed making it more efficient, and they changed their method for the rotor coating. The case make the GenV better, NOT the rotor coating.
The rotor coating was done this way for two reasons...1.) it was easier to control and apply and actually stuck and 2.)was designed to be applied thick, and would wear in the first couple of seconds of run time as its break in, sealing the rotors tighter to the case and themselves.
If the coating is coming off your M90 then its done. I would find you a good lower mileage GenIII off ebay, and buy it just for the rotors and be on your way. Running a M90 with no coating will not hurt it mechanically wise, just performance wise as it wont be able to pump as efficiently.
The company's out there that "recoat and rebuild" them are using spray on coating that you would use on piston skirts. nothing more, nothing less. Many times they do not re balance the rotors, and seen many of them not in time with each other when they ship them out. (they bind spinning them by hand). Cost effective when its all said and done? Nope. (for now but I am working on that) Cheaper to find you another supercharger and swap rotors, yes at this given time.
Magnuson does NOT recoat rotors. When they rebuild them, they do NOT reuse, or even rebuild rotors. They always install NEW rotor assemblies each and every time. They throw the old rotors in a recycling bin and call it a day. I know this for a fact, as I talk with them quite frequently about...stuff.
~F~
The rotors were machined to tolerances, and then cleaned and then coated. The machining left too smooth of a surface, and the coating would not stick to it in many cases cause it had nothing to grab onto but its self. Kinda like when you paint something, you have to scuff up the surface as prep...same concept here. Running rich, lean, meth, N20 wet or dry does not directly harm the rotor coating. If its peeling after this is shot through it...then it was on its way to peel anyway.
They (Eaton) realized their mistake with Magnuson, and all their rebuilds they were doing. So when they redesigned the 3800 for 2004's new model, they redesigned the M90 as well. The case changed making it more efficient, and they changed their method for the rotor coating. The case make the GenV better, NOT the rotor coating.
The rotor coating was done this way for two reasons...1.) it was easier to control and apply and actually stuck and 2.)was designed to be applied thick, and would wear in the first couple of seconds of run time as its break in, sealing the rotors tighter to the case and themselves.
If the coating is coming off your M90 then its done. I would find you a good lower mileage GenIII off ebay, and buy it just for the rotors and be on your way. Running a M90 with no coating will not hurt it mechanically wise, just performance wise as it wont be able to pump as efficiently.
The company's out there that "recoat and rebuild" them are using spray on coating that you would use on piston skirts. nothing more, nothing less. Many times they do not re balance the rotors, and seen many of them not in time with each other when they ship them out. (they bind spinning them by hand). Cost effective when its all said and done? Nope. (for now but I am working on that) Cheaper to find you another supercharger and swap rotors, yes at this given time.
Magnuson does NOT recoat rotors. When they rebuild them, they do NOT reuse, or even rebuild rotors. They always install NEW rotor assemblies each and every time. They throw the old rotors in a recycling bin and call it a day. I know this for a fact, as I talk with them quite frequently about...stuff.
~F~
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minichopper6hp
Banned - Busted For Scamming
Well as you can see, its perfectly capable of doing a low cost recoat. In the above picture, cost me no more than the powdercoat ($10) and an hour of my time.
GR8racingfool
New member
Awesomeness!
So you can rebuild these for $10.00 plus what ever a hour of your time is worth? Count me in. This include new bearings, and seals too? I have a shelf full of them I'll send you if you think you can handle a work load of around 25/30 rotor assemblies.
~F~
So you can rebuild these for $10.00 plus what ever a hour of your time is worth? Count me in. This include new bearings, and seals too? I have a shelf full of them I'll send you if you think you can handle a work load of around 25/30 rotor assemblies.
~F~
blueguy
The Blue One
minichopper6hp
Banned - Busted For Scamming
Im sure you are more capable of doing this than i am.