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View Full Version : New or rebult superchargers?


Midnight Autoworks
01-26-2006, 03:10 AM
I just wanted to post something about this, There IS a difference between the New superchargers and the rebuilt superchargers.
The new superchargers come with a .002 tolerence between the back of the rotors and the rear casing of the supercharger, they come with a .002tolerence between the edge of the rotors and the housing. The rebuilt supercharger has less tolerence between the back of the rotor and the casing becuase they shave the casing down slightly, and less tolerence between the rotor edge and the housing becuase of the coating they bake onto the rotors. Also this coating alows you to spray water befor the supercharger, the regualr coating on a new blower (teflon) peals off in about a week when you spray before so for customers asking for new superchargers we can only spray after.
Check out this article on how it works buy the people who rebuild our blowers:

What actually moves the air through a Roots blower is a pair of contrarotating, tri-lobe rotors which mesh as they turn. The tighter the fit of the lobes, the more efficient the blower is, however, there must be some clearance or the rotors won't turn. If the clearance is too great, the supercharger is inefficient because of leakage past the lobe edges. If the clearance is too tight, there is a high level of resistance to rotation. To both tighten rotor clearance and reduce friction Roots we coat each rotor with an abradable powder coating or (APC). During the break-in period, in the first few hundred miles of operation, a small portion of this coating abrades away, leaving the contact areas at the tips of the rotor lobes perfectly matched to each other and able to run extremely close

DustenT
01-26-2006, 03:46 AM
Also this coating alows you to spray water befor the supercharger, the regualr coating on a new blower (teflon) peals off in about a week when you spray before so for customers asking for new superchargers we can only spray after.

State your source.

So it's ok to run alcohol/gas/methanol fuels through an Eaton blower, but that teflon coating can't handle water? BS.

Midnight Autoworks
01-26-2006, 07:10 AM
Dustin, I didnt believe it at first either, (BTW my source is Magnason chargers), but yea, spraying a(m1) 1.3gpm nozzel at 150 psi water pressure starting at 6psi boost will strip the rotors, even faster if you use a solvent like methanol or isopropel. I didnt say it will handle alc but not water, I mean that water will strip it, but alc and methanol will strip it faster. have you torn yours down and takin a look since you started spraying? Or have you noticed a boost drop at all?

State your source.

So it's ok to run alcohol/gas/methanol fuels through an Eaton blower, but that teflon coating can't handle water? BS.

stormos
01-26-2006, 10:21 AM
this coul be interesting.....

DustenT
01-26-2006, 02:27 PM
The air and fuel from the carburetor enters the blower at the rear and is discharged from the bottom.

Why do the big v8 guys run roots chargers then? The coating must strip off super fast with gas.

It's an urban legend. I verified my setup with D/A, a company that does REAL research. I've had mine apart, and trust me, all is well. I still pull full boost. Spraying post-SC is not nearly as effective as pre-SC as the mist doesn't cool the roots and charger assembly.

Let me also add....Water Injection is probably the worst way to fight detonation. It is definetately the CHEAPEST way to do it, but not the best. It is a maintenance nightmare! Unless you have a warning light setup, you don't really know when you run out of juice. The correct way to do it is new software, larger injectors and probably an upgraded fuel pump.

AVOID Water Injection!

Midnight Autoworks
01-26-2006, 04:23 PM
Are you running straight water or water and some kind of alc?,Ho w long have you been running the water injection kit?

Midnight Autoworks
01-26-2006, 04:27 PM
Are you running straight water or water and some kind of alc?,How long have you been running the water injection kit?
D/A buys there chargers from Magnason chargers (the Distributer for Eaton in all of North America), and Magnason chargers is the one that says this is what happens, maby your running a very small amount of water?

DustenT
01-26-2006, 05:12 PM
Are you running straight water or water and some kind of alc?,Ho w long have you been running the water injection kit?

50/50 mix of water and denatured alcohol.

There are LOTS of people running water before the supercharger. I did a lot of homework on this before I installed it, did you?

Midnight Autoworks
01-26-2006, 06:20 PM
Yes, I did, I am telling you, we sprayed befor on the new superchargers and a month later we tore it down and the rotors were shiny metal, no gray coating at all, the powder coated rotors have showed no sign of break down.

TiPerformance
02-01-2006, 01:32 AM
I will step in to back up Joe on this, alot of the Pontiac Grand Prix guys have had problems with the teflon coating stripping off when using an injection system on their cars. Want proof look on Clubgp.com

NickG
02-01-2006, 06:17 PM
Interesting. When I was speaking with the tech at Magnuson (getting a customer's blower rebuilt), they suggested I spray the water BEFORE the blower, as it would help seal the rotors and build boost easier.

DustenT
02-01-2006, 06:24 PM
Interesting. When I was speaking with the tech at Magnuson (getting a customer's blower rebuilt), they suggested I spray the water BEFORE the blower, as it would help seal the rotors and build boost easier.

This is the same thing the Jim Downing told me. For what it's worth, my SC still builds boost at the same rate as before spraying water/alcohol. Maybe this is a problem on REBUILT superchargers?

Midnight Autoworks
02-03-2006, 10:05 PM
Our test was very simple: we mounted a brand new eaton M62 blower and began spraying before with 1.3gph nozzel and denatured alc and water mix of 50/50. we tore it down about 5 weeks later and the rotors were bone dry, no gray teflon coating. So we called aquamist and asked, they said they didnt know,we called coolingmistand they said some people do it and they havn't had a problem, some people reported the same thing. So we call magnason, they said they strongly do not recomend spraying through the supercharger for this exact reason although the gains of increasing the volumetric efficience by sealing the rotors was nice, you will strip the rotors and then basicaly require the water to maintain the same boost level. They did on the other hand have a rotor pack that would withstand the water alc, injection and we sent them a used supercharger to be rebuilt with the apc rotors and tried that blower. We tore it down 3 times in the last 2 months and the rotors are flawless. On our rebuilt apc rotor kits we spray 2 nozzles , one before and one after- the reasoning for this is that A: spray before to seal up the blower and cool the actual rotors to reduce the delta temp and B: spraying after the blower into compressed air charge, the chemical cooling from the actual evaporation of the mix into the air will happen at a much greater rate due to the air being heated and compressed.

DustenT
02-03-2006, 10:32 PM
Good luck with that. My alcohol/water spray setup was just an experiment for me. It was never really necessary.

NickG's ECU upgrade will take care of any fuel related issues, without adding any extra parts to maintain.

My water injection was always running dry without me noticing. This wasn't an issue for me because, as I said before, I didn't NEED to run it. When it runs dry, you need to disconnect the lines and re-bleed the system.

What are you going to do about people that live north of Florida? The injection lines will freeze in the cold weather. In theory the water injection system is a good idea, but in reality it is a pain in the ass. Plus you run the risk of blowing up your motor if it malfunctions or runs dry, too much maintanence for me.

Midnight Autoworks
02-03-2006, 11:03 PM
You should always tune the sysem to run without the water/alcohool.
The alc does not solve any fuel issues, it cools the charge to alow you more timing without detonation. We run a 12.1 air to fuel ratio without the injection, when we inject water/alc it apears even richer, look at the dyno on our site.
You should top off the tank every time you fill your gas tank. And if your running out too quickly, its either you need a larger tank, or you need to increase the on-set point and have it start at 8psi.
You do not have to re-bleed the system if it runs out, its self priming, unless you went with coolingmists cheepo check valve solotion instead of a proper soliniod.
Dustin, I thought you did your research, alcohool doesnt freeze.

andyman7931
02-03-2006, 11:09 PM
alcohool doesnt freeze.

yes it does... at -90 degrees C :biggrin:

DustenT
02-03-2006, 11:13 PM
You should always tune the sysem to run without the water/alcohool.
The alc does not solve any fuel issues, it cools the charge to alow you more timing without detonation. We run a 12.1 air to fuel ratio without the injection, when we inject water/alc it apears even richer, look at the dyno on our site.
You should top off the tank every time you fill your gas tank. And if your running out too quickly, its either you need a larger tank, or you need to increase the on-set point and have it start at 8psi.
You do not have to re-bleed the system if it runs out, its self priming, unless you went with coolingmists cheepo check valve solotion instead of a proper soliniod.
Dustin, I thought you did your research, alcohool doesnt freeze.

Are you running pure alcohol? A 50/50 mix of distilled water and denatured alcohol WILL freeze.

I ran a "proper selinoid" and I still had to reprime. I was running a 100 psi kit and I exploded the lines twice because it was below 40 degrees and everything was getting brittle.

Do you think that arguing with me is going to "win over" anyone and increase your sales? You already have a terrible rep on this site. Good bye.

Tyler
02-03-2006, 11:22 PM
This is getting ridiculous. :blahblah: :blahblah: :blahblah:

andyman7931
02-03-2006, 11:30 PM
http://www.318ti.org/forum/showthread.php?t=8771

Midnight Autoworks
02-03-2006, 11:33 PM
No, I do not think arguing with you will increase sales,my sales are just fine, this is a forum right? Discuss is what you do on forums. We advise our customers to run straight blue windshield washer fluid (it contains enough mythanol to do the job) in the system if its going below freezing out side or you can just run it dry and switch it off, you don't need the water alcohool if its that cold out side. If you have a soliniod and the pump is mounted below the water tank it will prime itself.