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Going mechanical with a Moose Omega Marine IP

I was driving around today so I took a video of my fuel pressure gauge. I accelerated from 35-65. Pressure started at 23 and hit a low of 18. I wonder how much output suffers from that drop....

 
The biggie I see is he was using it in enertia mode, not load cell. Enertia dynos tend to give pretty "giving" numbers with diesels. Your torque numbers should be disregarded. I've talked to a few dyno operators about diesels, and they've all said without an actual true crank rpm signal, the torque number is a guess at best and should be disregarded(I asked about it because it is nearly impossible to get a clear shot at my balancer for an rpm signal). The enertia dyno will never fully load your turbo, and being in 3rd did not help for an enertia dyno either. When doing enertia on a diesel, you need to be in the highest gear possible to actually load the engine, and hold it under load for any amount of time long enough to get an accurate reading. The correction factor he was using was pretty low, so I wouldn't worry about that. When dynoing a diesel for the best most accurate results, the dyno operator will start bringing the engine on power around the peak torque point, they will start adding load as they bring it on boost, and once it's on boost they will push the button for the dyno to do it's thing where it will load the engine down until torque begins to drop, then it will do a controlled acceleration to redline over around 5-10 seconds of time. This way the engine reaches full load at all rpm points, and spends an equal amount of time at each rpm point to get accurate measurements.
 
THEFERMANATOR said:
The biggie I see is he was using it in enertia mode, not load cell. Enertia dynos tend to give pretty "giving" numbers with diesels. Your torque numbers should be disregarded. I've talked to a few dyno operators about diesels, and they've all said without an actual true crank rpm signal, the torque number is a guess at best and should be disregarded(I asked about it because it is nearly impossible to get a clear shot at my balancer for an rpm signal). The enertia dyno will never fully load your turbo, and being in 3rd did not help for an enertia dyno either. When doing enertia on a diesel, you need to be in the highest gear possible to actually load the engine, and hold it under load for any amount of time long enough to get an accurate reading. The correction factor he was using was pretty low, so I wouldn't worry about that. When dynoing a diesel for the best most accurate results, the dyno operator will start bringing the engine on power around the peak torque point, they will start adding load as they bring it on boost, and once it's on boost they will push the button for the dyno to do it's thing where it will load the engine down until torque begins to drop, then it will do a controlled acceleration to redline over around 5-10 seconds of time. This way the engine reaches full load at all rpm points, and spends an equal amount of time at each rpm point to get accurate measurements.
Click to expand...
The process you describe about loading the engine and then letting it do a controlled acceleration to redline is what I was expecting so it did surprise me when that's not the process it used. This whole wheel dyno thing seems like witchcraft anyway because it just doesn't make sense: horsepower is calculated from torque, not the other way around so the fact that the dyno apparently measures horsepower and then calculates torque is beyond me. Perhaps they use the electrical conversion of 746Watts = 1Hp by using electrical load? Regardless of how they do it, what you said is the same thing that my operator told me: that without an rpm signal he'd be able to get a horsepower number and not a torque number, so that is corroborated. Pulling in overdrive doesn't make sense to me in regards of accuracy. I would think you would wanted the closest to 1:1 in all gears to get a more true number. However, he didn't ask me what my final drive ratio is either, so I guess that doesn't matter. I do get that having it in overdrive would load it more, and would load the turbo more, but that should in theory just raise the horsepower higher if it makes the turbo do more. That explains the lower boost than what I see on the street. However I'm just not sure it's worth putting that added stress on overdrive in the trans. I think I'll pass on that. When I find a good load cell dyno I will still run it in direct. So I guess the bottom line is that the dyno finds a number somehow and we go from there.

Based on my 1/4 mile time, I don't think the horsepower number the dyno spit out is unreasonable. I also know at what RPM I shut runs 3 and 4 down, so I know how far off the RPM was off at the top end of the run. So rather than disregard the torque I am going to do a correction to it and we'll see how that stands up in future tests.

So we know that the Horsepower to Torque equation is HP=(TqxRPM)/5252. Solved for Torque it's TQ=(HPx5252)/RPM. According to the graph for run 4 I was making 343hp at 2926 RPM. Solved for Torque that is 615.67ft-lbs. Which is inline with the graph. So the math works.

The graph shows that I let off at just under 3350, when in reality I let off around 3650, so at the top end it's off about 300 RPM. So if instead I bump the RPM up by 300 RPM in the equation I will get different numbers. (343x5252)/3226=558.41. So according to this correction I was actually making more like 560ft-lbs of torque.

Regardless of any of this. I'm already working on plans to go back with my Ferret adapter to see if they can get an RPM reading off of that. If they can, then I'll go back for another baseline. The point of the dyno is for me to use it as a tuning tool, so if I can show that a change helped or hurt my power, that's what I need. When I have the opportunity I will make the 3+ hour trek to a place that dynos diesels more and see what kind of number they read. Or maybe I'll just yank the engine and take it to the engine dyno 2 miles down the road and bypass all the mumbo-jumbo.
 
THEFERMANATOR said:
The biggie I see is he was using it in enertia mode, not load cell. Enertia dynos tend to give pretty "giving" numbers with diesels. Your torque numbers should be disregarded. I've talked to a few dyno operators about diesels, and they've all said without an actual true crank rpm signal, the torque number is a guess at best and should be disregarded(I asked about it because it is nearly impossible to get a clear shot at my balancer for an rpm signal). The enertia dyno will never fully load your turbo, and being in 3rd did not help for an enertia dyno either. When doing enertia on a diesel, you need to be in the highest gear possible to actually load the engine, and hold it under load for any amount of time long enough to get an accurate reading. The correction factor he was using was pretty low, so I wouldn't worry about that. When dynoing a diesel for the best most accurate results, the dyno operator will start bringing the engine on power around the peak torque point, they will start adding load as they bring it on boost, and once it's on boost they will push the button for the dyno to do it's thing where it will load the engine down until torque begins to drop, then it will do a controlled acceleration to redline over around 5-10 seconds of time. This way the engine reaches full load at all rpm points, and spends an equal amount of time at each rpm point to get accurate measurements.
Click to expand...
Oh I forgot to ask: why don't the dynos just grab RPM from your OBD2? The dyno I was on had that capability, but since my OBD2 is only running glow plugs and ABS it was useless.
 
ak diesel driver said:
Be interesting to talk to your pump guy and see if he has any guesstimate of how many CCs your leaving on the table with the lower fuel pressure.
Click to expand...
Yeah I'll definitely do that though honestly I'm not worried about getting every drop of fuel out of it at the moment. This year I'm focusing on controlling the heat from the fuel I have by adding WMI and relocating my intercooler radiator to the front bumper. So maybe late this year or early next will be fuel system upgrades.
 
The 5252 figure is for a gas motor, it does not relate to diesel at all, that # is where the tq/hp should cross or meet on the graft for a gas motor, if it doesn't the dyno isn't set correct --- this again is for gas not diesel... there is no direct correlation between tq & hp like that with a diesel... the tq can & will be at much different places with us..

There is one dyno shop here that the operator knows how to skew the numbers to show what ever you want to see, no one other than kids use him due to the false numbers ...

On the other hand there is a diesel only shop that most serious folks use, he takes about 1/2 hr to set the dyno, he measures the tires, checks the air psi in them, he must know the gearing ratio, and you will be in direct tranny wise... and if you can't give him the info he needs he won't dyno it period....

I have seen several trucks make pulls there and he will load it much harder than can ever be done on the street to the point that it starts to pull the motor down.. he claims that's the only way to get true numbers with turbo diesels..

I wasn't going to say anything but sense it was brought up your pull didn't load the motor very much or it didn't appear to looking at the vids, and that is considering boost numbers as I saw them.

Non the less I think you are on the right track so far, keep up the good work :smuggrin:

And I'm NOT discounting your numbers here, I just think you weren't given a fair pulling session this time is all...
 
The point of dynoing in the highest gear possible on an enertia dyno is actually 2 fold. 1st part is it allows the dyno to have as large a sam0ling window as possible. In say 3rd you start your run at 40 and end it at 65 which gives it a 25mph window to read, but in 4th you could have started at say 50 and run it up to 90 which would have given you a 40mph read. This allows the constant load to have the most load against the engine as possible also, and it also reduces torque to the tires decreasing traction problems. As to the torque reading, it must know exact rpm's vs load to figure torque. Hp is how fast you hit the wall, torque is how far you carry it before you stop. So for hp it is sim0ly measuring how fast it is accelerating the rollers, but for torque it has to know exact rpm readings cs load to come up with an accurate torque value. This is also why most dyno operators won't use obd2 data readi,gs as they can lag behind by a half a second or more easily as j1850 is a slow data transfer rate at best.

As to your numbers, you already said your boost numbers were down on the dyno vs the street, so you know he wasn't loading it as hard as just running down the road does. That tells you right there the engine wasn't being pushed up, so your numbers may actually go up once you actually load it. I know though several duramax guys dyno'd on mustang enertia dynos, and got low to mid 500 numbers, then they tried a load cell dyno and barely broke 400. On the other hand, I've seen trucks that couldn't fully spool up the turbo only do 500 on an enertia dyno, but do alnost 700 on a load cell where they actually loaded the engine and got on boost. With the narrow rpm window of a diesel, enertia dynos just tend to not do well unless it was one with about a 5-6 foot diameter roller that weighs 10K lbs with an eddy current break to add extra load. Diesels need to be loaded down for the turbo to work, otherwise your just spinning your wheels. The dyno you used is capable of loading it, but I'm guessing he did enertia to save the wear and tear on his equipment.
 
Great summation. 1:1 no TC involved (fully locked) should be 'the way' for AT. Same thing for MT, 1:1 if at all possible. Load it like the earth it sits on. You cannot rotate the earth to cheat. Inertia is dynamic and is beyond my brain so this is where my comment ends. lol
 
The 5252 thing works for any engine, gas or diesel, 2 stroke, 4 stroke, any thing. It is a mathematical formula.
Torque= (HP x 5252) / RPM
HP= (Torque x RPM) / 5252

Diesel engines just dont normally hit tye high rpm to offset the torque and show the hp rating higher than torque. If you had a diesel engine that can produce 1000 ft lbs torque and can run 9,000 rpm, you would see a high horse power low torque engine at it's top end just like high rpm gas engines.

You can throw Watts into it also if needed,
1 HP = 745.699872 Watts

They are all constants, like an inch, foot, yard, mile. Just invert the formula and do the math.
 
pacificdrumma said:
Conestoga is now showing a "Super Moose", claiming 205cc fuel... who's gonna be that guy?
Click to expand...
Maybe some day..... Actually, IIRC, the pump they did for me was the largest they would do their standard warranty on. Above that they have to make custom parts that are really under a lot of stress to make that fuel so their warranty doesn't apply. HOWEVER, they said they would of course stand behind their work and they would fix the pump if it fails and be very fair with the repair bill. Since my truck is a daily driver and camper tower, that didn't seem like a good route. If ever make a hot rod 6.5 I'd definitely love to try that pump!
 
sctrailrider said:
The 5252 figure is for a gas motor, it does not relate to diesel at all, that # is where the tq/hp should cross or meet on the graft for a gas motor, if it doesn't the dyno isn't set correct --- this again is for gas not diesel... there is no direct correlation between tq & hp like that with a diesel... the tq can & will be at much different places with us..

There is one dyno shop here that the operator knows how to skew the numbers to show what ever you want to see, no one other than kids use him due to the false numbers ...

On the other hand there is a diesel only shop that most serious folks use, he takes about 1/2 hr to set the dyno, he measures the tires, checks the air psi in them, he must know the gearing ratio, and you will be in direct tranny wise... and if you can't give him the info he needs he won't dyno it period....

I have seen several trucks make pulls there and he will load it much harder than can ever be done on the street to the point that it starts to pull the motor down.. he claims that's the only way to get true numbers with turbo diesels..

I wasn't going to say anything but sense it was brought up your pull didn't load the motor very much or it didn't appear to looking at the vids, and that is considering boost numbers as I saw them.

Non the less I think you are on the right track so far, keep up the good work :smuggrin:

And I'm NOT discounting your numbers here, I just think you weren't given a fair pulling session this time is all...
Click to expand...

I agree with what you're saying, Chris, I need to get on a different dyno to get some "real" numbers or try to work with this one some more to see if they'll run it in load cell mode......but I do have to disagree with you on the 5252 thing. As Will stated, it's a mathematical constant that is used to calculate the one from the other. Any dyno graph you look at, at the wheels or at the crank, you can pick any point on the curve and calculate the corresponding horsepower or torque number by using that equation. Up until this weekend, I thought that horsepower was ALWAYS calculated from torque, but apparently in the case of wheel dynos, they measure horsepower and then calculate the torque. Just one other thing I have learned from this experience!

THEFERMANATOR said:
The point of dynoing in the highest gear possible on an enertia dyno is actually 2 fold. 1st part is it allows the dyno to have as large a sam0ling window as possible. In say 3rd you start your run at 40 and end it at 65 which gives it a 25mph window to read, but in 4th you could have started at say 50 and run it up to 90 which would have given you a 40mph read. This allows the constant load to have the most load against the engine as possible also, and it also reduces torque to the tires decreasing traction problems. As to the torque reading, it must know exact rpm's vs load to figure torque. Hp is how fast you hit the wall, torque is how far you carry it before you stop. So for hp it is sim0ly measuring how fast it is accelerating the rollers, but for torque it has to know exact rpm readings cs load to come up with an accurate torque value. This is also why most dyno operators won't use obd2 data readi,gs as they can lag behind by a half a second or more easily as j1850 is a slow data transfer rate at best.

As to your numbers, you already said your boost numbers were down on the dyno vs the street, so you know he wasn't loading it as hard as just running down the road does. That tells you right there the engine wasn't being pushed up, so your numbers may actually go up once you actually load it. I know though several duramax guys dyno'd on mustang enertia dynos, and got low to mid 500 numbers, then they tried a load cell dyno and barely broke 400. On the other hand, I've seen trucks that couldn't fully spool up the turbo only do 500 on an enertia dyno, but do alnost 700 on a load cell where they actually loaded the engine and got on boost. With the narrow rpm window of a diesel, enertia dynos just tend to not do well unless it was one with about a 5-6 foot diameter roller that weighs 10K lbs with an eddy current break to add extra load. Diesels need to be loaded down for the turbo to work, otherwise your just spinning your wheels. The dyno you used is capable of loading it, but I'm guessing he did enertia to save the wear and tear on his equipment.
Click to expand...

I see what you're saying about overdrive giving a larger sampling window. The meat of the run was definitely over quickly and I was struggling with traction thanks to my damn Gov-Lock giving me a one-tire-fire at operating speed. I still worry about putting that stress on overdrive though. If it was a run on a load cell, would running in 3rd make less of a difference?

I'm going to go back to the dyno and talk to them about this some more. The first thing I want to do is see if they can read rpm off of my Ferret adapter. The next thing I'd like to do is see if their dyno is capable of running in load cell mode and if it is, if they'd be willing to do that with my truck. Maybe like you said, they can do it and they just choose not to for wear and tear reasons.

Will L. said:
The 5252 thing works for any engine, gas or diesel, 2 stroke, 4 stroke, any thing. It is a mathematical formula.
Torque= (HP x 5252) / RPM
HP= (Torque x RPM) / 5252

Diesel engines just dont normally hit tye high rpm to offset the torque and show the hp rating higher than torque. If you had a diesel engine that can produce 1000 ft lbs torque and can run 9,000 rpm, you would see a high horse power low torque engine at it's top end just like high rpm gas engines.

You can throw Watts into it also if needed,
1 HP = 745.699872 Watts

They are all constants, like an inch, foot, yard, mile. Just invert the formula and do the math.
Click to expand...

Yeah Mr. White! Yeah SCIENCE!!
 
A friend of mine just gave me the pics and videos he took at the dyno Friday. He had some different shots of the runs, so it's fun to see the different perspectives. I like seeing the front suspension flex during the pulls. Enjoy.

Run 1 Outside Alternate

Run 2 Outside Alternate

Run 3 Outside Alternate

Run 4 Outside Alternate

Otto 1.jpg Otto 2.jpg
 
For best results you want a 1:1 ratio, but for enertia dynos you need overdrive to get the spread and traction. That was why I asked before hand what dyno. Your numbers may not change, but if your boost was down, then I'm betting the results will change(primarily the torque). Your hp doesn't sound far fetched for the amount of fuel you have. That dyno is just not optimal for doing diesels, but it sounds like you already know that.

As to traction issues, I remember a few years ago seeing a twin turbo duramax put down over 750 on his break in tune, problem was he was spinning the tires to the point they were smoking doing it. They had already brought out extra straps, but it was raining off and on, so water kept dripping onto the roller.
 
THEFERMANATOR said:
For best results you want a 1:1 ratio, but for enertia dynos you need overdrive to get the spread and traction. That was why I asked before hand what dyno. Your numbers may not change, but if your boost was down, then I'm betting the results will change(primarily the torque). Your hp doesn't sound far fetched for the amount of fuel you have. That dyno is just not optimal for doing diesels, but it sounds like you already know that.

As to traction issues, I remember a few years ago seeing a twin turbo duramax put down over 750 on his break in tune, problem was he was spinning the tires to the point they were smoking doing it. They had already brought out extra straps, but it was raining off and on, so water kept dripping onto the roller.
Click to expand...
Yeah after having the experience and reviewing the footage I've come to the conclusion that this isn't a great dyno for doing a diesel. Perhaps he could change it to a load cell operation, but if he isn't familiar with running it that way then would I really gain much? You know because then he may make a different error that totally skews the result. I do still feel though that this dyno and operator will work find for me as a testing tool. I can use it to test any changes I make in the future to see what the effect is on peak horsepower (if any). So I am still planning on going back to see if we can get a good RPM signal to work off of and then lay down some more runs. These runs should then be good ones to use as my baseline to compare to. For all of the testing runs I'll still just run in direct because I feel that it's more repeatable for how my trans tuner works and because I don't want to stress OD. When I someday go to a good dyno that can really load me, then I'll keep OD as an option if I need it. I appreciate your insight.
 
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