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Re: m62 ld9 build!!
Wednesday, September 04, 2013 1:57 PM
I was actually getting ready to do a little napkin math on the flows requirements before I clocked out at 5, but someone already beat me to it haha.

Something also to keep in mind is that the CFM your engine requires is directly related to the RPM at which it is turning. A 2.4L at 6500 RPMs will need less volumetric flow than one spinning at 8000 RPMs. So you could actually see manifold pressure decrease through the powerband if you choose to use a higher redline than 6500 RPM and keep the redline of the blower the same. This doesnt necessarily mean less power, but its another reason to not just spin your motor to the moon for the hell of it.




Re: m62 ld9 build!!
Wednesday, September 04, 2013 2:27 PM
people have been overspinning eatons for years with great results. these maps provided by eaton might as well be toilet paper as far as i am concerned. they are going to put a limit on it well below its ACTUAL rpm maximum to save face and bottom lines for warranties. i overspun my m45 for months and months without issue and so have MANY MANY others on here.

besides, look at the graphs, just because they stopped the plot at 14,000 does not necessarily mean thats where the redline is. it just means they chose not to rev it any higher for the testing graphs.

also, keep in mind, by doing smaller snout pullies it also speeds up the hit so to speak, so instead of max cfm at XXXX rpm, its going to come on a little bit sooner which also means it stays at full boost LONGER.. i watched this happen 4 times on my m45 setup. when i first put it on i was using an underdrive crank pulley, then i went to stock sized crank pulley, then the oversized crank pulley, and ultimately, going from the 2.5" snout to the 2.4" snout... the "hit" came on faster and faster with each change and i LOVED it.

the trick with these blowers is to get things as light as possible so when you DO these pullies that cost more power you are relieving as much spent on the blower power as possible. this means lighter rotating assemblies, pullies, flywheels, etc. i dont JUST believe in freezing cold IAT's chris.




Edited 3 time(s). Last edited Wednesday, September 04, 2013 2:33 PM


RIP silver car. You will be missed.
Re: m62 ld9 build!!
Wednesday, September 04, 2013 3:58 PM
SweetnessGT wrote:

Doing some really fast research for you:

Eaton Supercharger Data

That page shows that if you have a gen 3 model your recommended redline on the charger from Eaton is 14,000 rpm. That solves that question.

Here is a flow chart for the 3rd gen M62:



That chart was found here


I had a few minutes to sit down and look over everything better now that I'm home.

Im curious about this graph. Is it actually from Eaton? If Im reading it right (thats a big if with me sometimes haha), those flow numbers seem low compared to what I'm calculating. I've always been under the impression that for a roots S/C the inlet flow equaled the outlet flow since the air is being compressed in the intake mani and not the blower itself.

For there to be positive pressure in the engine the outlet flow of the S/C has to be greater than the air that the engine is consuming on its own without the blower.

From what I've calculated a 2.4L at 6500 RPM is consuming 865CFM of air. Just eyeballing it off of the graph, the S/C would have to be turning over 24000 RPMs to even make zero boost.

Ill make a plot of calculated flow based on the displacement and RPM of the blower if anyone is interested.









Re: m62 ld9 build!!
Thursday, September 05, 2013 9:55 AM
-Z Yaaaa- wrote:

people have been overspinning eatons for years with great results. these maps provided by eaton might as well be toilet paper as far as i am concerned. they are going to put a limit on it well below its ACTUAL rpm maximum to save face and bottom lines for warranties. i overspun my m45 for months and months without issue and so have MANY MANY others on here.

besides, look at the graphs, just because they stopped the plot at 14,000 does not necessarily mean thats where the redline is. it just means they chose not to rev it any higher for the testing graphs.

also, keep in mind, by doing smaller snout pullies it also speeds up the hit so to speak, so instead of max cfm at XXXX rpm, its going to come on a little bit sooner which also means it stays at full boost LONGER.. i watched this happen 4 times on my m45 setup. when i first put it on i was using an underdrive crank pulley, then i went to stock sized crank pulley, then the oversized crank pulley, and ultimately, going from the 2.5" snout to the 2.4" snout... the "hit" came on faster and faster with each change and i LOVED it.

the trick with these blowers is to get things as light as possible so when you DO these pullies that cost more power you are relieving as much spent on the blower power as possible. this means lighter rotating assemblies, pullies, flywheels, etc. i dont JUST believe in freezing cold IAT's chris.


There is so much wrong in this one single post that it blows my mind Brad.

If you didn't show up, completely ignore the math, throw all the engineering and testing into the wind and say "lots of people overspin their superchargers" - then I would have been disappointed in you. You've been ignoring solid fact for a long time, choosing rather to follow the fine line between "smart" and "dangerous". I thought you would have learned something recently.

You completely ignored the CFM aspect of a supercharger - the maps stop because the supercharger stops producing useful CFM at that level and starts to make a dangerous amount of heat in its place. A roots supercharger is a positive air pump just like an engine, it has a limit as to what it can flow in stock form. Just because you want to spin it to 16,000 rpm doesn't mean there is ANY gain whatsoever in the volume of air being put through the supercharger - in fact because the pressure remains constant or even slightly increases your Delta T map ramps up even further.

In fact I don't think you even looked at the Delta T map and read it right. Thats the temperature gain at a certain RPM & Pressure - ON TOP of atmospheric. Look at the map, add 2-3 more PSI and move the curve over 2,000 more RPM mentally and see just how much you're strapping on top of atmospheric. You'll be at almost 250 degrees on TOP of atmospheric - I don't care how much cooling you throw at it that's a disgustingly dangerous amount of heat to make a few more PSI and very little extra volume.

But you're right - go ahead and strap a smaller pulley on and overspin it.

Before you want to chime in I do realize that you had a ported and polished charger that will have good tolerances and a higher CFM flow rate... you probably WERE making some extra power past the intended use of the charger because of this. But a fast calculation shows that if you were running a 7" crank pulley (I think you were but I could be wrong) and the 2.4" pulley listed in your profile you were spinning 17,500 rpm @ 6000 rpm... let alone past that.

I dug up a M45 chart for your review... I'll assume you don't know how to read it but I'll present it anyway.




I may be wrong but I believe the stock pulley was 2.8" on the M45 GMSC... with the intended stock crank pulley the charger was slightly overspun at a 6500 rpm Redline (just shy of 15,000 rpm). We know that the GMSC made at most 6 psi in stock form(on a nice cold night) but usually averaged about 5... I'll be generous and assume 6 which is a pressure ratio of 1.42 which puts us right at the center where volumetric efficiency is at its peak ( close to 70% ). The bottom line is in M^3/hr but an online converter shows that 600 M^3/hr = 353 cfm... I believe it's a general acceptance that 150 cfm = 100 hp so the charger is capable of flowing about 225 hp into the engine at its intended redline of 14,500 rpm. This again sounds about right... not many people have gotten much more out of it than that - right?

The M45 is known to be most efficient at its lower RPM's and this map is showing it... many people dyno'd 165 whp in stock form with this charger which would be at about 250 cfm at a pressure ratio of 1.42... that CFM on this map is about 425 M^3/hr... so if you look GM intended to make its power in the meat of the powerband, not at redline... at about 60% efficiency. If we follow the map along that line you can see that after that point (11,000 rpm on the blower at the pressure ratio of 1.42) the engine would be at... 4000 rpm. If we follow the line the efficiency drops to 55% where the blower is making more heat right around 13,000 blower rpm or about 4700 rpm on the engine. It's still making power but less efficient and really any gain in rpm is being negated by heat. The delta T on the stock setup is 120 degrees F above ambient... fairly hot but that's why their power level is a bit poor and its why they tuned the car mega rich... in the event that some idiot didn't put high octane gas in and cried "warranty" after the grenade went off. That makes total sense. Oh and the charger is also chewing up 24 hp at engine redline... no wonder they only made about 165 whp or a 35 whp gain over stock. Of course - that's what GM intended for when they designed the kit.

Now, this is where your argument for meth comes in and ai FULLY AGREE with it. Those efficiency percentages change quite dramatically and power goes up. Even on a stock GMSC setup your meth advocacy rings true and the delta T would drop quite a bit bringing up the efficiencies on the map giving more power across the entire compressor map... but that's keeping the unit within its operating range.

But lets look at your final setup real quick... out of curiosity. I want you to see the math behind your claims...

A quick microsoft excel spreadsheet with my assumed characteristics of your car shows this chart of engine rpm vs supercharger RPM:

1000 2916.66
1500 4374.99
2000 5833.32
2500 7291.65
3000 8749.98
3500 10208.31
4000 11666.64
4500 13124.97
5000 14583.3
5500 16041.63
6000 17499.96
6500 18958.29

I looked up the post where you had corrected your cam timing making 6-7 psi of boost... so I'll assume you made 7 psi (far more efficient psi) but flowed more cfm. a 7 psi pressure ratio is 1.49 so we can realistically look at the 1.5 part of the map.

First off, at 7 psi and the RPM's quoted a fast glance at the Delta T map following its curve shows you were at about 215-225 degrees F above ambient before any kind of cooling at redline. Pretty high but you were doing your best to cool the charge and keep efficiency up. On a warm summer day we're talking about 300+ degrees before cooling after the rotors.

Second off following the map you hit the meat of the supercharger at just above 2000 rpm on the engine... the stock setup hit that area at around 2700 rpm. This is where your "hit" you describe comes in... you spun the charger up quicker enabling you to get into its range a lot quicker... and it looks like you were only slightly less efficient doing it. But then things change quickly after that and by about 2800 rpm you are losing efficiency. by 4100 rpm you were around 58% efficient before cooling and by 5000 rpm you were almost off the map at 50%... at this point if you look at the power consumption chart you were eating 30 hp to make your power.

But you weren't done... you still had some powerband to go on the engine so lets see how you fared by extrapolating since Eaton felt the need to "not test" beyond the 15,000 rpm... considering 14,500 rpm was where they deemed the charger was no longer efficient enough to plot.

At 5500 rpm you were at 45% efficiency soaking up almost 40 hp to spin the blower...

At 6000 rpm you were at less than 40% efficiency eating up what looks to be almost 50 hp to spin the blower...

And at 6500 rpm engine redline you were spinning the blower at 19,000 rpm... I can't even extrapolate how low this efficiency is but I'll assume its around 35% and about 65 hp to spin the blower.

Your delta T is around 225 at that point, you are literally making a ton of heat above ambient at a very low efficiency while gobbling up a lot of power to spin the blower... probably about as much power as your gain.

Lightening the drivetrain to help negate the loss in HP from spinning more helps your bottom line a bit yes BUT the point isn't the HP lost to spin the charger it's the fact you're losing that power to spin the supercharger where it's not even helping you make power anymore. Whats the point of losing 25 extra hp at that point if the charger can't breathe enough air and overcome the heat to make that loss worth it?

(Bear in mind these are all hypothetical numbers I'd need you to confirm your mods etc to solidify them but I think they're in the ballpark.)

Again I'll re-iterate... YES your cooling mods help shift all these and yes your ported blower will let you flow more cfm (horsepower) but the bottom line is the efficiency drop off on this charger from its intended redline to the one you were spinning is in the ballpark of 15% at a drivetrain loss of what looks to roughly be an extra 25 hp. It's a power soaking heat pump and wasn't intended to be run like that.

This is the equivalent of running a T25 turbo to 6500 rpm on an LD9... it simply isn't going to make any more power no matter WHAT you do it and a compressor map will show you the exact same data. It is designed to make great down low power at the cost of top end power... which is does very well. The M45 is designed in exactly the same way. I am digging around for a Gen3 M62 compressor map but I cannot find one as of yet... it's simply going to flow more volume though at those same lower RPM's and if you keep it in and around its intended redline it will stay moderately efficient.

I really hope looking at all that data makes sense to you and shows you why the manufacturers tests stop at a certain point on the map. They weren't being lazy and they weren't saying "hey this is the safe limit for the supercharger based on warranty specs". Can you overspin a supercharger? Sure if you aren't afraid for the bearings or rotors then of course you can... but does it truly give you a top end gain? Only the charts and math will show you the truth of what gain you may see at the cost of a faster deterioration. The bottom end gain is huge as the chart shows and you hit peak efficiency really quickly which is perfect for daily driving... but the gain up near peak torque is dropping off fast. At that point - as in the turbocharging world with a T25 - you need a bigger supercharger... which will sacrifice bottom end hit for top end power.

I fully expect you to say "people have been doing it for years and my rotating assembly is lightened and I am cooling the crap out of it and it worked awesome"... but you really need to lay the car on a dyno and work through the pullies while datalogging to see whats going on. Sure the car ran "fine" but what were the TRUE gains?

You've ignored sitting down and looking at an engine with an engineering eye for a long time, choosing to rather pick up information from others and the internet and apply that to theories that you have constructed. That's one way to do things but there's a reason that engineers get paid good $$ to design these engines and design these parts and provide the testing data. It's not guys with an internet connection working on their driveways being asked by GM to "engineer" a supercharger kit for their cars... right?

You can do things the way you do them on your own car Brad but to give advice to others to follow the same path is irresponsible - unless you plan to pay for Cody's engine if anything happens to it due to him following your advice?

There's being cautious, there's being stupid, and there's being smart. I'm trying to convince him to be smart and work everything out before he makes his decisions so he can make informed ones to bring his M62 dream to life. Bring your theories to Honda-Tech and see how far they go with extremely experienced and knowledgeable builders who go back and forth through data like this all the time. There's a reason all this data is floating around and a reason why these tests were done and a reason why every compressor made has a compressor map strapped to it that *shows* you its abilities.

I will say one thing - that ported charger of yours took it like a champ. A 32% overspin over its intended design is pretty hefty... G-Laders grenade at far less than that.

I would hate to see a piston in the event of a meth-kit failure, though.

Hopefully we can still be friends.

-Chris-



-Sweetness-
-Turbocharged-
Slowly but surely may some day win this race...
Re: m62 ld9 build!!
Thursday, September 05, 2013 12:19 PM
Oh and Brian... that chart shows that within its efficiency range the 3rd gen M62 can flow about 300 hp worth of air (150 cfm per 100 hp)... which sounds about right if not a tad generous.

I believe our engines only flow about 220 or so CFM through them but that's at 100% ve. Engine CFM calculation hurts my brain, to be honest. So many variables to consider not to mention that VE changes as it approaches and passes peak torque.

-Chris-



-Sweetness-
-Turbocharged-
Slowly but surely may some day win this race...
Re: m62 ld9 build!!
Thursday, September 05, 2013 1:37 PM
jeas chris, i feel honored that you would spent a good portion of your evening to try and "school" me.... however, i am sorry that in this instance i seem to be more "in the real world" than you seem to be. i go by what i have learned by actually doing it, not what some computer theorizes the experience should be. yes i overspun my m45, but not really that much more than others have or continue to do. ask them all, they will all tell you the same thing i do, overspinning it makes the car faster.

as far as your statement of me choosing to run the line between dangerous and smart i will say i resent that. yes it was dangerous to drive my car without a fire extinguisher. i will say it wasnt too smart of me to leave out the extingusiher but just because i did doesnt mean it has anything to do with my experience on the supercharger. the fact that you would relate the two together as such sadens me. i did what i did with my s/c because i did my homework on what people have actually done, NOT what a computer printout says. i went one further than most did and i feel as though it gained. it certainly do not feel it lost anything.

the supercharger was definitely being overspun, but not to the way too far extremes a 1.9" pulley would do. even i would never go that far. in fact, there truly is no way you COULD go much further. the crank pulley is as large as you can get without hitting the bolts on the timing chain housing cover. now, you MIGHT be able to squeeze a 2.35 pulley on the m45 snout by shaving off some more but it would be so close it would be mere thousanths from working or not working. we had to take some off the snout as well as in the inner diameter of the pulley to get the 2.4" on there. i feel the setup i had truly was the best an m45 can have. i did not get a chance to prove it, though.


i dont know where you got 300+ degrees but that is just not the case. you were however close, i dont understand what you mean by PLUS ambiant though?

i used an aeroforce interceptor gauge set on IAT for the following. i religously kept track of it as well...
m45 with 2.4" snout, 7" crank. 6500 engine redline. absolutely no cooling mods whatsoever. 80-90* day. crusing IAT's around 120-130*. 210-230* iat's under WOT. recovery sucks, it just stays hotter and hotter until you drive it on the interstate for about ten mins, then it comes down some.

same setup exactly, just using a 375cc meth/water nozzle set to come on at 5psi. 90-100* iat's under WOT. recovery is great, comes down right where it was before a pull. at night, i would see 75-85* wot pulls.

i saw the results with my own eyes, felt them with my own ass, and will continue to advise people to overspin their blowers because i feel works great.

yes heat is a killer of power. i have said it time and time and time again around here. i am not advocating overspinning a blower without cooling mods, thats just insane and will net nothing. it is imperative that IATs be kept down. this is why i have always been on the hunt for cooler IATs no matter how strange or ludacrous the method. if it works, id use it.

oh and whats this talk about a meth kit failure? seems to me the j-body world has more issues with failing fuel pumps including aftermarket than failing meth pumps. just food for thought. i only had one issue with my meth kit throughout using it. my anti siphoning solenoid would not hold back the lot of the engine vaccum at idle and low speeds. but that did not render the kit unfuntional, it just simply let fluid entire the engine under vaccum. i attribute this to use of tap water during experimenting when distilled water should have been used.





Edited 3 time(s). Last edited Thursday, September 05, 2013 2:23 PM


RIP silver car. You will be missed.
Re: m62 ld9 build!!
Thursday, September 05, 2013 1:40 PM
oh and i will say steigemeier's "porting" on the m45 really isnt much if anything at all. the boost triangle inside leaves much to be desired. i feel it can be opened up a lot more and more cfm can be put through the engine. i also feel this small boost window is why the m45 has been, as you said, limited to around 225whp without nitrous or a turbo upping things. they merely smooth casting flaws and might open up the tb opening some as well as the intake ports some but as far as that boost window is concerned, they dont do much and i feel can certainly do more to it. i havent seen a stock one to compare so i dont know just how much it was opened but like i said i feel it can be improved.



RIP silver car. You will be missed.
Re: m62 ld9 build!!
Thursday, September 05, 2013 2:14 PM
i want a specific post for this one.

please show me a real world redline of an m45, not just a plot graph that chooses not to show what it CAN do, morover what eaton warranties it at.

you say i overspun it 32% well i dont understand where you are getting the redline numbers from? again just because the graph stops at XX does not mean that the number it stops at is the redline.


the way i understand it the max rpm of a blower is limited due to heat build up in the snout. the bearings wont last long, or so i have read. steigemeier has come up with a nifty fix for this, boasting very good heat discipation with their "venom cooler". i have not yet found out exactly what this is but i am assuming its some type of heat exchanger built into the snout itself which cools the bearings and oil inside it. i plan on having them install one in my m45 snout and just running like a tranny cooler of some kind with a circulation pump to make it all flow. the use of this, along with lightening the rotors, opening up the boost window inside the manifold for more cfm flow, more meth/water and the use of a second water only purge system will net over 250whp from an m45 and reliablity to boot. just me.. hopefully i get the chance to see if it works one of these days.


Edited 1 time(s). Last edited Thursday, September 05, 2013 2:27 PM


RIP silver car. You will be missed.
Re: m62 ld9 build!!
Thursday, September 05, 2013 2:26 PM
Brad - before I begin... you said:

"all these graphs you present - NONE of them have anything to do with meth/water injection."

I stated VERY CLEARLY to you that you are correct in all your theories that your meth injection WILL INCREASE THE EFFICIENCY #'S on these maps. Re-read what I wrote ... I clearly stated that.

I ALSO said that any porting to your charger will ALSO increase CFM at any given point on the maps too, which will skew the map too.

I 100% conceded this to you Brad. Your air density will increase, dropping the Delta T and giving you a big benefit.


Also - I can understand you resenting that statement and I thought carefully about including it in there but I felt it needed to be said. You are all about overspinning the charger and using meth to make up for it. My comment had NOTHING to do with what happened to your car but rather the fine line you ran with the supercharger and the tuning. It's your car - you are very free to do that my friend but all I'm saying is to recommend that to others is irresponsible.


Next up you are talking about IAT's... are you getting this reading after the charger has compressed the air? Is this reading coming from the runners going into the head? Delta T is not an IAT reading, it's a IAT + compressed air reading. In a turbo setup I can read this post intercooler to see what the air intake is going into the throttlebody but you would have to get that reading in the runners of the supercharger. Let me know on that because if that's the case then of course this skews the maps in your favour. (I already conceded that didn't I? lol)


You keep talking about the "hit". I didn't ignore your argument - again read what I read. Read it again - maybe two more times. I showed on the maps with my spreadsheet that what you felt you were doing in fact was EXACTLY what was occurring - and yes you were holding your boost pressure LONGER. But you were holding it into a far higher supercharger range with a higher pressure ratio thereby making more heat in a compounding fashion. Look at the Delta T map and see the difference in heat due to pressure... now carry that past the 14000 map to the 19000 rpm that you ran on the charger. You made MUCH better power down low at the behest of the top end and at the behest of the superchargers efficiency range - by a LOT.


Lastly - I am not one to ignore "real world" results. I stated that you need to put your car on a DYNO and change your pullies and see what your real world results are. You will probably get horsepower to come on earlier and the torque curve will ramp up faster but the question is how much extra "power" were you making spinning the supercharger after the 14,000 rpm mark.

That data coupled with a temperature reading after the rotors as well as the usual stuff we need from the engine (timing advance/knock, afr's, etc.) will let you see just how efficient that meth was for you.

If you honestly were getting 100 degrees Fahrenheit after the air was compressed in the 5000-6500 rpm range then you definitely blew their stock maps out of the water, Brad. But your meth will ONLY affect the Delta T map as well as air density (efficiency) on the compressor map... your meth will NOT allow the charger to flow more CFM past the 14,000 rated mark.

You will make more EFFICIENT power out of the blower... yes. But you will NOT make more power than the blower is rated to flow. Not without porting it quite a bit and even then THAT is limited.

Re-read what I wrote and compare it to the data - I did not ignore what you said to me at all - in fact I proved some of it to be true and some of it to be dangerous. Your desire to keep the charge air cool 100% benefits the superchargers efficiency but the RPM that it spins at can be quite dangerous when you weigh in the fact that it's not flowing any more CFM, it's quickly exiting its efficiency range and it's eating up a lot more rotating horsepower to do so.

THAT is what I was trying to show you - that you had an awesome bottom end but you may not have gained as much as you liked in the top end. If you get that setup back up and running it would be very beneficial to you (especially to shut me up ) to get the car on a dyno and have it tuned.

I think you may have seen a hell of a torque curve with a big gain, and a 220-230 whp peak somewhere around 5000-5300 rpm with a quick drop off in horsepower after that point.


As an aside - I DO have real world data on a setup much like yours Brad. A slightly higher compression engine with cams, every bolt on, a 7" crank pulley and a 2.5" supercharger pulley with the meth NOT running... and I Dyno tuned it for 4 hours. I have over 25 graphs showing changes and I have a final dyno graph showing the characteristics of the engine on that pulley. What I don't have is compressed air temperatures unfortunately and what I didn't have was a functioning meth kit at the time. Torque peaked early as all my math above predicts and HP gain slammed into a wall before 6000 rpm. My tuning flattened this out so it would hold with a small drop off but the charger was definitely out of air.

The car made 209 whp and 198 wtq on a dynapak.... I can safely say the supercharger was running at its peak and past what I'd feel safe running it at RPM wise but it wasn't my car and the owner was thrilled with the results. As long as he's happy, I'm happy... but I still told him to put a bigger pulley on.

It wouldn't have made MORE horsepower after 6000 rpm... the CFM flow isn't there. But it sure as hell would have made more horsepower all the way along the curve, as well as torque. The curves would have been EXACTLY the same except higher on the graph.

Hopefully you can absorb all this, chew on it a bit and realize that in a sense we are agreeing on many aspects of this debate, but disagreeing on the safety vs. benefits of a supercharger over-spin.

I just want you to embrace the engineering side of things a bit - the more that people do this kind of homework the better their setups will be built and the more that top 25 WHP list will be pushed.

-Chris-



-Sweetness-
-Turbocharged-
Slowly but surely may some day win this race...
Re: m62 ld9 build!!
Thursday, September 05, 2013 2:29 PM
chris i edited my first post a lot after rereading your book. please go back and read, i took out a lot of it because i was wrong in some instances.


and yes, the IAT sensor is placed inside the manifold where it reads boosted air temperature.


Edited 1 time(s). Last edited Thursday, September 05, 2013 2:31 PM


RIP silver car. You will be missed.
Re: m62 ld9 build!!
Thursday, September 05, 2013 2:32 PM
-Z Yaaaa- wrote:

i want a specific post for this one.

please show me a real world redline of an m45, not just a plot graph that chooses not to show what it CAN do, morover what eaton warranties it at.

you say i overspun it 32% well i dont understand where you are getting the redline numbers from? again just because the graph stops at XX does not mean that the number it stops at is the redline.



Searching up on the internet I have not found anything 100% concrete unfortunately Brad. All research points to a 14,500 rpm redline on a Gen5 M45 supercharger... I REALLY wish Eaton had more info on their website about this kind of stuff.

The thing about a compressor map is that it's entire existence is to show the efficiency range of the compressor. Take a look at that map up there, the island is WAY to the left which is why it stops at the perceived redline.

Redline doesn't denote that the charger will throw up its guts all over the road... it's denoting the "choke point" for the charger... the point where it simply cannot cough up more air for you to make HP with.

I can get you to blow as HARD as you can through a McDonalds straw... thats the point where your lungs have no more CFM (flow) to give. Getting you to take the deepest breath you can and blow that hard longer isn't going to put more flow through the straw unfortunately - it's your limit.

Now I can hand you a paper towel tube and do the same. You will flow MORE cfm (volume) through this but at a much lower pressure and at less pressure to yourself and your lungs. That's a larger displacement supercharger right there... an M62 or an M90.

Hope that makes sense, man.

-Chris-



-Sweetness-
-Turbocharged-
Slowly but surely may some day win this race...

Re: m62 ld9 build!!
Thursday, September 05, 2013 2:35 PM
and what is this safety aspect you keep chewing on? are you worried the blower is going to spit its guts out or something? show me an m45 that has done it on a j-body being overspun and ill believe its dangerous. irresponsible to advise others to over spin? how exactly? are there any proven results that overspinning it decreases its liftspan? are there any proven results that show any negative effects by over spinning the m45? i certainly havent seen a one, but i could wrong. if you simply show me why its dangerous and irresponsible i could begin the path to recovery. just show me the proof and ill be on my way.



RIP silver car. You will be missed.
Re: m62 ld9 build!!
Thursday, September 05, 2013 2:41 PM
one big thing you failed to address... when using meth/water it actually physically takes cfm OUT because it displaces air LOL. so by using meth/water it actually makes a blower more restrictive. but because of its cooling properties and ability to add octane and an oxidizing fuel into the mix you can also make more power with adding in timing and the replacement of some gasoline with methanol.

again, id like to open up the boost window more to increase cfm. trying to squeeze all that air through that teeny little window is an exercise in futility. the edges of mine are rough and jagged, liking increasing turbulance and hot spots. like i said, there is much more room for improvement.



RIP silver car. You will be missed.
Re: m62 ld9 build!!
Thursday, September 05, 2013 3:08 PM
Well according to my math 7/2.5 stock m62 pulley on mine and md crank pulley ill still be over spinning at 19600 rpm so before i make a desision on a pulley ima run the stock blower pulley and md crank pulley and see what results i get power and boost wise with that set up and my intercooler etc then try other pulleys and see what hsppens temp and hp wise. I agree research is needed but i believe research only gives you a good starting point and past that these charts mean almost nothing to me there are way to meny variables once you start modifing things for any chart to be a one size fits all and im on brads team if it wasnt for ppl who push things and try new stuff our hobbie wouldnt even be here @!#$ if brad had dyno numbers who knows it could put the m45 set up on the map for being amazing. I dont care what a map says as fair as flow wise cuz this blower will blow a stock m62 gen 3 or 2 witch ever mine is outta the water but i will over spin mine perioud and run a venom cooler to help lessin heat soak ppl gotta think out side the box here this isnt science its call hot rodding wanting to go fast and brad they called me nobby in high school lmao


I Love My J ♡
Re: m62 ld9 build!!
Thursday, September 05, 2013 3:25 PM
nobby (haha) i dont know if the venom cooler is really gonna do a lot for heat soak but it may. i believe the general purpose is to sustain a more even temperature throughout the case while also helping cool the snout bearings and oil down increasing lifespan.

and as far as this CFM debate goes, chris... im wondering... is it the rotor size that is the CFM downfall or is it the size of the boost window in the case? i feel it has to be the window because mini cooper guys are somehow getting 250-275whp out of their eaton gen 5 m45s with a smaller engine.



RIP silver car. You will be missed.
Re: m62 ld9 build!!
Thursday, September 05, 2013 3:34 PM
Well they do claim it lowers temps significantly all togeather and it cant hert and i wish they had pics of it but it sounds like a coolant line they root threw the snout to cool oil and keet the snout heat from soaking case and adding to the heat being made by the compression of air but thats just my impression and thanks everybody for the math and charts you guys pirty much gave me all i needed and i really apreciate all the help :-)


I Love My J ♡
Re: m62 ld9 build!!
Thursday, September 05, 2013 4:07 PM
What's the map and efficiency of a 2.4 with 7" crank ad a 2.9 TVS .. Any maps? Whp goals?
Re: m62 ld9 build!!
Thursday, September 05, 2013 4:11 PM
id say with a built motor, stock compression, you should do 350whp pretty nicely on meth and tuned well.



RIP silver car. You will be missed.
Re: m62 ld9 build!!
Thursday, September 05, 2013 4:17 PM
What if a drop to a 2.7 or so pulley?
Re: m62 ld9 build!!
Thursday, September 05, 2013 4:51 PM
Holy roller blading martini drinking Jesus, I missed a lot today. I'll have to sit down and read those novels when I get back from the store.



Re: m62 ld9 build!!
Thursday, September 05, 2013 5:13 PM
So I can estimate around 350 to the wheels with a 2.6 pulley on the TVS.. About right? Sorry to thread jack..

Re: m62 ld9 build!!
Thursday, September 05, 2013 5:36 PM
lol its a lot to soak in brian. after rereading chris's novel a few times i concede that he is the winner. i will still stay true to my beliefs that overspinning the m45 is worth it (when spraying a ton of meth/water through it for cooling) but again, not much to go off of there because i have no dyno proof to back up my claims. one thing i feel needs noted here, in the beginning i advised AGAINST nobby's plan to run such a teeny snout pulley. i am all for overspinning when not when its going THAT far. i think chris needs to hear this because i feel as though he thinks i believe just throwing the smallest pulley on every blower is my best course of action and advise as such when this just isnt true. ive done research, ive known that there is a line between producing nothing but heat and no more cfm but you are never going to find that line if you lack imagination then just bow down and follow the manufacturer's stock guidelines.

i firmly believe a lot of the m45's downfalls lay within the inability to get the air that it actually IS producing through the case. i wish steigemeier would produce flow bench results for their port work on the m45 because i am not so sure its even worth the money. they do not go very aggressive with the porting.

which leads me to our next debate. portng a supercharger. i know next to nothing about it and would love to learn more. ive read SOME things like a good port job on the boost V window has a rolled smooth edge with absolutely no sharp edges or ridges and is best opened up to where the rotors are exactly paralell to the edges. anybody know much about it?



RIP silver car. You will be missed.
Re: m62 ld9 build!!
Thursday, September 05, 2013 6:48 PM
hmmm, so looking into getting my rotors coated, i found a company called jonbondperformance.com that can recoat the rotors. service is $150 if you provide the rotor to case tolerance or you can send the blower for them to do it but they also rebuild it, no exeptions. which from what i am reading, costs around 650 bucks. this i simply cannot fathom as to why its so spendy. the case bearings are literally $40 dollars. i will say that our m45 is the hardest one to replace them though because they sit in blind holes with no access from behind. my m62 uses the exact same bearings only there IS access to them from behind, so instead of having to die grind them out for removal, you simply set the bastard in a press and punch em out. so much easier, wow. but again, way too much money to install two case bearings and rebuild the snout. you can get snout rebuild kits on ebay for like $70 bucks. all you need is a press. we did it in 15 minutes on mine. ...ANNNND i will say that after god knows how many miles and gallons of meth and beatings while being overspun between chris taetsch and jered methe, i will say the used snout bearings and coupler looked and felt just as nice as the new ones we put in. the case bearings, however...were shot. my blower sounded like it had rocks being ground up inside they were so bad. but once i got those replaced it was as quiet as can be.

so, if anybody needs their blower rebuilt, hit me up i can do it.

JB-P boasts a 1-3 psi increase by doing their rotor coatings. ive read that it helps a ton with heat as well. i believe this to be a no brainer and will definitely be getting mine re-coated at some point.

so nobby, keep all this in mind for yours.



RIP silver car. You will be missed.
Re: m62 ld9 build!!
Friday, September 06, 2013 7:03 AM
Oh i noted that all 150$ sounds good to me 1-3psi thats what i like to hear thats for shure


I Love My J ♡
Re: m62 ld9 build!!
Friday, September 06, 2013 12:57 PM
I'm a bit busy today so I won't be able to get to most of the above for a bit but I did want to look at Shawn's question about the TVS - I assume it's the standard 1320 you want to go with so I found that map on Eatons website.

My first impression of the efficiency chart at a glance was "HOLY GOD - now THAT is a supercharger" - you'll see why.




^^^ Now THAT supercharger is meant to make some power - and do it efficiently. Look at how centered the island is on the map... yum yum yum. 1400 M^3/hr translates into 824cfm or approximately 540 hp of flow. Unreal.

I did some fast math on the 7" crank vs 2.9" pulley... it's not small enough.

Here is the math on a more optimal combo - 7" crank and 2.7" snout pulley putting the supercharger to it's soft redline on the compressor map (and still quite efficient):

1000 2592.5
1500 3888.75
2000 5185
2500 6481.25
3000 7777.5
3500 9073.75
4000 10370
4500 11666.25
5000 12962.5
5500 14258.75
6000 15555
6500 16851.25
7000 18147.5

It's hard to work out a pressure ratio since I don't really know what it's going to do... all we can do is assume. This blower is capable of a BIG pressure ratio - 2.4.... which equates to a very safe 20.5 psi of boost. Some people with ecos have taken it to 27 psi...

Let's assume you can get it to run at 14.5 psi. That's a 2.0 pressure ratio. If you draw a line across the 2.0 you'll see where you float and if you follow the RPM's you'll see that by 3000 rpm you'll be pushing almost 300 cfm or 200 hp of air at a very acceptable 67% volumetric efficiency before any kind of meth cooling.

Of course it keeps getting better because the charger gets MORE efficient as you hit the meat of your powerband rather than less efficient like the M45. You're at 4200 rpm and your efficiency has increased to about 71%.... and that's before you spray any meth. Looking at the chart at that point you should be flowing about 310 horsepower of air approaching your peak torque. You can assume you'll have a really really vertical torque curve with this supercharger.

After that the limitation is going to be your tuning and what your ENGINE can flow. This supercharger can seriously push the living crap out of an LD9 without losing a beat... it stays between 70%-65% from this point on and that's with zero cooling helping it. This is a supercharger that's made to perform between 2500-5000 rpm and clearly with the right pulley it's going to do just that.

You could literally run this to a 7000 rpm redline on a quad 4 and keep making power so long as the engine can breathe it in.


Cody - I glanced above and saw you don't believe in all these maps and all this math. Why would you throw this to the wind? This isn't the end all and be all of how the engine is going to do - as you said there are FAR too many variables to call this perfect but if you look at the above you can now see that Shawn can ballpark his expectations and choose his supporting mods based on what this supercharger is capable of. That's the entire point of doing all this work - so that you pair the right modifications with your compressor so that you can reach a set expectation.

He would have started with the wrong pulley and spun the supercharger too slow, now he knows to go with a 2.7 rather than the 2.9. Wouldn't you like to save some money and make some informed choices based on a bit of homework?


Hey Brad - you can wipe your butt with the above compressor map after you print it out. I think it'll give you a big boner and a reason to put the M45 up for sale.

Glad to see you coming around to the engineering side.

-Chris-



-Sweetness-
-Turbocharged-
Slowly but surely may some day win this race...
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