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Anyone know the max speed on an Eaton 112? I've heard 14,000 is the official statement, but some are spinning as high as 20,000. It's going to be part of a turbocharged/supercharged diesel project, blower will be for the low end, then bypass and the turbo will do all the work once boost hits 30+psi, so the supercharger will be just freewheeling, so I think that I could push it a bit more. Thoughts?
 

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Mine hits 15,600 pretty regularly. You can go higher, but at some point the rotors will twist too much (I've spun M90s to 18,000+; but they have shorter rotor packs). I'll be going to 16,250 this year and am not worried in the least.
 

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I believe the suggested max rpm listed for these blowers is related to heat and efficiency. The heat generated becomes the limiting factor. You get to a point of diminishing returns after a certain point because of the heat. Its not that the bearings or rotor pack can't candle being spun at higher speeds. Its the heat.

I've heard reports of eaton superchargers being spun to the point that the rotor pack swelled up began rubbing the housing. Some even have reported strange noises coming from the blower while on the dyno which alarmed them and caused them to shut the engine down. Then discovering they couldn't restart the engine because the rotor pack was swelled up and had to wait 10-15 minutes before being able to restart the engine.

This is where water methano injection has come in and allowed guys to safely spin their blowers past the manufactures suggest max rpm and make more power. I have lots of customers with non-intercooled m112's Eatons on Mustangs and T-Birds who are seeing 230 degree discharge temps at only 7-8 psi. With methanol injection air charge temps drops to 130's.

Rodney
 

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^ That's partly right - but you'll never see 230* intake temps at 7-8 psi. Where you will see 230* intake temps is without a decent working bypass during cruise. Under boost, the charge will actually cool off. These blowers are excellent at moving air, and at slower RPMs actually more efficient than TVS blowers. Where they start to fall down is under high boost levels.
 

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^ That's partly right - but you'll never see 230* intake temps at 7-8 psi. Where you will see 230* intake temps is without a decent working bypass during cruise. Under boost, the charge will actually cool off. These blowers are excellent at moving air, and at slower RPMs actually more efficient than TVS blowers. Where they start to fall down is under high boost levels.

I don't understand how you come about all this with decades of experience working with these blowers. The air coming out of the supercharger, or any compressor for that matter, doesn't get cooler as you go down the track. It gets hotter. The longer you hold the compressor in boost the more heat its going to make. Why would we need intercoolers if the air charge cooled off?

And this whole thing about the only time you would see 230* is if you were cruising and the bypass was not working (in closed position). You tell me me why SCT data logs are showing 230-240 degree discharge temps at the end of a 12+ second 1/4 mile run with non-intercooled M112 supercharger at only 7-8 psi and no water meth. I have lots of customers running the Ford Racing SVO supercharger (non-intercooled M112) who all see the same thing.

The statement about these superchargers are excellent at moving air. What is excellent? Do they give you instant boost at low rpms? Yes. But do they heat the air up more then other forms of compressor such as turbo's and centrifugals? Yes. Why do you think they got the nickname "heaton"? They add considerably more heat to the air when compared to other types of compressors. Its common to see a non-intercooled Vortech hit 230 degree discharge temps at around 12 psi at the end of a 1/4 mile pass. Thats 4-5 more lbs over the Eaton. A good working turbo set up can better this by even more.

Rodney
 

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Anyone know the max speed on an Eaton 112? I've heard 14,000 is the official statement, but some are spinning as high as 20,000. It's going to be part of a turbocharged/supercharged diesel project, blower will be for the low end, then bypass and the turbo will do all the work once boost hits 30+psi, so the supercharger will be just freewheeling, so I think that I could push it a bit more. Thoughts?
13,500 rpm is the max blower speed. Those numbers are from Eaton btw.
 

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Rodney - I'm not interested in arguing with you; but all the answers to your questions (including data logs, experiments, and a little bit of humor) can be found here - warning; it's a lot to digest:

http://forums.corral.net/forums/5-0-5-8-engine-tech/1253086-eaton-m112-install-5-0-ltd-pics.html

This is just my latest round of screwing around with an M112. I really think you'd be hard-pressed to argue against the hard data and empirical evidence in there.
Neither am I. Good luck trying to convince people on here that the air charge temps after the compressor get cooler as you go down the track.

Rodney
 

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I used Eaton 112 rotorpack in a Magnum Powers case and spun it 24K RPMs for years at the track. This in a Lightning pickup. Still have the blower in the garage just in case someone equals my times with similar equipment.
 

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Neither am I. Good luck trying to convince people on here that the air charge temps after the compressor get cooler as you go down the track.

Rodney
Re-read my post. Please don't mis-quote me or put idiotic words in my mouth.
 

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^ That's partly right - but you'll never see 230* intake temps at 7-8 psi. Where you will see 230* intake temps is without a decent working bypass during cruise. Under boost, the charge will actually cool off. These blowers are excellent at moving air, and at slower RPMs actually more efficient than TVS blowers. Where they start to fall down is under high boost levels.
:confused:
 

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LOL - and the sentence before it reads what?

"Where you will see 230* intake temps is without a decent working bypass during cruise."

Nowhere do I actually mention what happens during a pass. For the love of God, people - READING IS FUNDAMENTAL!

Here's real-world, firsthand proof:

http://forums.corral.net/forums/10838241-post693.html
 

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Re-read my post. Please don't mis-quote me or put idiotic words in my mouth.
Well then there's where the confusion is. I responded to your post and made some comments. You didn't respond or comment on any on the points I made and instead referred me a link.

That link is 30+ pages long. Don't have the time to go through it. The last page has nothing to do with supercharger and has a lot of links to music videos on youtube. If this isn't what you meant then respond and address the points I made.

Rodney
 

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With all due respect, I don't have the time or desire to spoon-feed you what you should already know as a purveyor of meth injection (BTW - "specialists" (in your sig) doesn't have an apostrophe in it in this case). The information in the thread I referenced is accurate and voluminous; because there's so much of it, I've done my best to intersperse it with humor to make it an interesting read. You really should take some time and read it, you'll learn a lot; as the information you've shared is anecdotal and not accurate. When I don't know something, I say so - as you can tell about my post regarding the M122. That's how I learn.

The OP could probably glean quite a bit of useful info from it as well. I took the time to do it to "share the wealth;" I'm not interested in selling anything to anyone. I enjoy hotrodding.

Ct. Topgun - what numbers did your lightning end up putting up? I've never pushed any Eaton over 20k...
 

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LOL - and the sentence before it reads what?

"Where you will see 230* intake temps is without a decent working bypass during cruise."

Nowhere do I actually mention what happens during a pass. For the love of God, people - READING IS FUNDAMENTAL!

Here's real-world, firsthand proof:

http://forums.corral.net/forums/10838241-post693.html

Are you serious? Busting my balls over the statements I have posted and using this as proof. You have air charge temps at 220-230 while in vacuum cruising. Thats a huge problem right there and not normal. Might be because the blower is sitting right over the headers.

Then the moment you crack the throttle and move some air the temps drop a little over ten degree's. Really? You never went full throttle and no one can really tell what the run time was or what the outside air temp is? How about you bring the engine up to temp and data log a full pass at WOT. Where's the IAT? Is it still in the #5 intake runner? Move the sensor and place it in the discharge tube you fabricated connecting the blower outlet to the throttle body. Sensor gets heat soaked in the lower intake manifold.
 

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With all due respect, I don't have the time or desire to spoon-feed you what you should already know as a purveyor of meth injection (BTW - "specialists" (in your sig) doesn't have an apostrophe in it in this case). The information in the thread I referenced is accurate and voluminous; because there's so much of it, I've done my best to intersperse it with humor to make it an interesting read. You really should take some time and read it, you'll learn a lot; as the information you've shared is anecdotal and not accurate. When I don't know something, I say so - as you can tell about my post regarding the M122. That's how I learn.

The OP could probably glean quite a bit of useful info from it as well. I took the time to do it to "share the wealth;" I'm not interested in selling anything to anyone. I enjoy hotrodding.

Ct. Topgun - what numbers did your lightning end up putting up? I've never pushed any Eaton over 20k...
Buddy I think your project is cool. Not trying to knock it. I'm sure you had fun doing it too. As for your comment on not having time to "spoon feed me" what I should already know. You can keep that to yourself.

If you've done a lot of work with eatons as you said you have you would know those air charge numbers at cruising are excessively high to begin with. If you are going to patronize me and this is the example you are going to use to validate your post then that explains everything.

Your excessively high air charge temps probably everything to do with the blower sitting over the header, pulling hot air from the corner of the engine bay off the header and IAT location. The information I shared is accurate and won't standby and have you say otherwise. This build has its obvious short comings and shouldn't be compared to other builds.





Robert Pearson's SVO Supercharged Ford Thunderbird 4.6L SOHC V8 With Stage 1 Adjustable Boost Activated Trunk Mount Water Methanol Injection System

  • Ford Racing Non-Intercooled SVO Eaton Supercharger (Eaton M112), 7 lbs of boost
  • 245 degree peak air temps before water methanol injection (during 1/4 run on 90 degree day)
  • 120-130 degree peak air temps after water methanol injection (during 1/4 run on 90 degree day)
  • 296 rear wheel horsepower without water methanol injection
  • 352 horsepower after water methanol injection
  • 56 horsepower gain (19% gain in power)
  • AIS Stage 1 trunk mount water methanol injection system
 

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Rodney: Read more, talk less. You clearly have no idea what you're talking about. Read that whole thread and learn; or don't. I don't care. Your grasp of how these things work is tenuous at best. 130 mph at 3,300 lbs with a 306/Eaton M112 combo with no charge cooling on pump gas clearly shows I know what I'm doing. And there's more to be had; once I replace the block I've split in half.

To the OP - my apologies; I was trying to be helpful. I'm done here.
 
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