PTO Dyno

[jgendr]

Hey all, been reading lots of stuff here and lots of Ideas and great posts.

I have been into diesel trucks ever since I bought my 01 Dodge, I have admin'd a couple of website's on hotrodding our toy's. I have learned tons on how to juice up the dodges and such. We have get-togethers to see how our tinkerin has helped. I'm proud to say that my 01 dodge lay's down and impressive 535hp and 1132lbf of torque where the rubber meets the road and I get an impressive 23 mph on the highway. We certify these numbers on a big dyno machines at our events.

Now I'd like to try tweaking my yanny just to see what I can get. I have searched the web and have found a couple of pto dyno's on fleebay and some new ones too. these are the ones used in the Nebraska tests. I want to build one just for S & G's, ( because I like to play) and start some tweakin.

Here is my thoughts:

1. An old electric break utility trailer axel (for creating a load)
2. a 1000lb load cell (to measure the load)
3. a inductance transducer ( to keep track of RPM's)
4. A PTO shaft and slip clutch ( Just in case! LOL )
5. A data logger ( to log all that data for compairision )


Have any of you bright folks out there ever thought of trying this and if so Give me some of you thoughts and suggestions.

I want to show some real world results of what a little tweaking can net you and pass that info on to all! If I can conservatively double or triple the hp in my dodge I know these little power houses are capable of far more than they are built.

If you could get (Safely 10 - 20 - 30 more HP) out of your tractor wouldn't you want to know how? Heck the sled pullers can do it why can't we?

Thanks in advanced

JG

 

[bobodu]

Personally, I'd fear tearing up a drive line hooking a dyno to my PTO with a hopped up engine. Wheel slipping is one thing,but how would you calculate a safe slip on a PTO?

 

[jgendr]

Easy, you can calculate the slippage, by calculating your target hp and troque you are shooting for. Simple calcuations:

Torque = JM * rpm per second / 9.551
where JM represents the Polar Moment of Inertia of our inertia dyno's flywheel.

If we don't know the Polar moment of Inertia for the flywheel (and our flywheel has a constant thickness cross-section) we can calculate it with the formula:
JM = (W * r ^2) / 32.16 / 2
where W represents the flywheel weight in pounds and r is its radius in feet.
Once you have the torque, it is easy to calculate the horsepower with the standard formula:
Hp = Torque * rpm / 5252
Keep in mind that the rpm in the last formula must be the average rpm during the sampling period.

 

[dqdave1]

yah, that is what I thought !!!!!!!!!!!!!!!!!! whatever you just said???????????
You know more about dynos than I ever will. Maybe I need to stay a a Holiday Inn Express. I can turn the key on my New Holland and move the throttle for more power!

 

[jgendr]

ROFLMAO!!!!! Now that was funny!!!!!!


very simple, The axel will be used as th load, the break backerplate will be free floating and the load sensor will be set at 1 ft from center off the backer plate. the hub of the axel break will be hooked to the tractor via the pto shaft.

so that being said, as the tractor is set to pto speed (540) the hub rotates. as you apply an electrical current to the trailer break it starts to put a load on the pto. that load is measured by the load sensor in actual foot lb's of torque. as you apply more current to the break assembly more torque is required to overcome the force.

so if my tractor is rated at 28 hp at the pto the calculation looks like this:

28hp = torque * rpm / 5252
torque= 28hp * 5252 / rpm(540)
torque = (28*5252)/540
torque = 272.3 ft lb's



So theoretically adding a turbo at 5 - 7 lbs of boost, a litte more fuel, and a little more timing will give you aproximatlly 10 - 12 hp.

Adding 7 - 10 lbs of boost will = 15 - 20 hp, 10 - 15 lbs of boost and an intercooler could get you upwords of 30 + hp.

 

[zzvyb6]

Well the high road would require a computer, National Instruments A/D Card, maybe some software (Student version of Matlab or Excel), the load cell, tach and some conditioning amplifiers. A nice science project.

Taking the low road would take a water pump or generator, some maybe an adjustable resistance load. Use tractor rpm, and water pressure for indication of load and hp. Trailer brake is a good idea. Assume you mean to attach a moment arm onto it and measure the braking force. A grain platform scale can be used for this, too.

Any way to combine hobbies so you could buy a truck power absorber and use in on the tractor?

 

[SPYDERLK]

Here is my thoughts:

1. An old electric break utility trailer axel (for creating a load)
2. a 1000lb load cell (to measure the load)
3. a inductance transducer ( to keep track of RPM's)
4. A PTO shaft and slip clutch ( Just in case! LOL )
5. A data logger ( to log all that data for compairision )

If you could get (Safely 10 - 20 - 30 more HP) out of your tractor wouldn't you want to know how? Heck the sled pullers can do it why can't we?

Thanks in advanced
JG

Great list! Consider, to avoid heat problem:

1. 
   Lower a bushog into water.
   2. Is this a torsion/torque cell? That would work on the hog arrangement.
   4. Slip clutch only needed if hog locks up.

larry

 

[jgendr]

Well the high road would require a computer, National Instruments A/D Card, maybe some software (Student version of Matlab or Excel), the load cell, tach and some conditioning amplifiers. A nice science project.

Taking the low road would take a water pump or generator, some maybe an adjustable resistance load. Use tractor rpm, and water pressure for indication of load and hp. Trailer brake is a good idea. Assume you mean to attach a moment arm onto it and measure the braking force. A grain platform scale can be used for this, too.

Any way to combine hobbies so you could buy a truck power absorber and use in on the tractor?

Thanks ZZ;

That's more on the line of what I was thinkin. Eventually I would like to use some sort of Data aquisition system for more reliable results, however initally manual calculations will be used. Keeping in mind this is on the cheap just to prove concept and baseline readings for power mods.

Explain the power absorber to me, I'm not sure what you talking about. I'm open to all contributions, cause that's the way progress is achieved.

thanks

 

[SPYDERLK]

Explain the power absorber to me, I'm not sure what you talking about. I'm open to all contributions, cause that's the way progress is achieved.

thanks

Beating water or air is a good way to absorb power. Hence the suggestion to vary your load by lowering a bushog into water. Rev it up, set hydraulics to lower bh slowly, observe the power curve.
larry

 

[DRL]

How about mounting a big water pump like an irrigation pump so it came pivot a little, then stop it from pivoting with the scale. Slowly close a valve on the output of the pump and read torque on scale. Would not have to worry about heat like with the brakes.

DRL

 

[bobodu]

So you can figure the target torgue etc.....can you guesstimate when something in the driveline is gonna let go??? I know pulling an engine is a pain but it pales compared to a broken tranny.

 

[john_bud]

I'm proud to say that my 01 dodge lay's down and impressive 535hp and 1132lbf of torque where the rubber meets the road and I get an impressive


23 mph


on the highway.


JG

So, you're the joker that's going 23 mile per hour on the highway, eh? Typical dodge guy.....



(just yanking your chain !)

 

[Treemonkey1000]

So, you're the joker that's going 23 mile per hour on the highway, eh? Typical dodge guy.....

(just yanking your chain !)

NOw that one made me laugh! Is he all white hair and can't see over the steering wheel as well? They sell strobe light tachometer testers that are pretty accurate to test PTO RPM. I test those types of things here where I work. As far as loading the PTO shaft why not drive a hydraulic ram to it's limit or have a valve that restricts the flow but increases the pressure required to drive it? Is that making sense?
I am in the camp that my little Kubota is not new so I don't want to hop it up an break it. Getting a little more performance is nice to have.. Maybe funny car headers and wrinkle wall ag tires?

 

[jgendr]

So, you're the joker that's going 23 mile per hour on the highway, eh? Typical dodge guy.....



(just yanking your chain !)

ROFLMAO!!!! Ah No, 65 - 70 is good for me and yes I do get 23 MPG's. Good one though. But I do have a freind that resembles that remark HA HA HA!!! save that for another story.

Treemonkey; I'm very interested in what you said. do any of the tach you are talking about rs-232 or usb capable? if so post somemore info. Manufacture, part #'s and such. My Yanny has the same motor as the fx24, fx32 and fx42. So if the right combination of mods can be done I can theoretically juice it up to 42 pto hp and not exceed the limits of the tractor. a 14 hp gain at the pto isn't somthing to not considerif it is cost effective. What is cost effective you ask? How's $250 or less. Interested now?

 

[Treemonkey1000]

Ok I will look at work tomorrow for some of the Tachs. I don't remember them being USB ported. They read out on a LCD display. But I Imagine there are some with USB capability.

 

[dfkrug]

Great idea, JGENDR. I hope you follow it thru. A recent TBN poster has
completed a small simple turbo installation and could use a dyno.
http://www.tractorbynet.com/forums/...oject-tractor-contined-turbo.html#post1329205

As far as loading the PTO shaft why not drive a hydraulic ram to it's limit or have a valve that restricts the flow but increases the pressure required to drive it? Is that making sense?

Regarding the use of hydraulics to make a controllable measurable load, I
would use a PTO pump as TREE suggests, but use it with an adjustable
constriction (valve) and pressure monitoring. You would have known
volume, based on RPM and pump displacement, and you increase the
restriction until the engine starts to slow down. Your oil will heat up,
but not as fast as dry brakes.

Keep us posted. Good science is about controlled experiments and
measurable results.

 

[xlr82v2]

Here's something I found on Google...

Tractor Dynomometer

 

[SPYDERLK]

Great idea, JGENDR. I hope you follow it thru. A recent TBN poster has
completed a small simple turbo installation and could use a dyno.
http://www.tractorbynet.com/forums/...oject-tractor-contined-turbo.html#post1329205



Regarding the use of hydraulics to make a controllable measurable load, I
would use a PTO pump as TREE suggests, but use it with an adjustable
constriction (valve) and pressure monitoring. You would have known
volume, based on RPM and pump displacement, and you increase the
restriction until the engine starts to slow down. Your oil will heat up,
but not as fast as dry brakes.

Keep us posted. Good science is about controlled experiments and
measurable results.

Hydraulics is a good way to go but, pressure and volume only gets you within about 20% of the true HP due the unknown loss values. You could assign a 15-20% number to it and come close, but since the plan is to measure PTO output torque and rpm you really only need the hyd to provide a custom tailorable load. The other measured parameters provide the accurate HP measurement.
larry

 

[dfkrug]

Hydraulics is a good way to go but, pressure and volume only gets you within about 20% of the true HP due the unknown loss values. You could assign a 15-20% number to it and come close, but since the plan is to measure PTO output torque and rpm you really only need the hyd to provide a custom tailorable load. The other measured parameters provide the accurate HP measurement.
larry

It is true that hyd systems are only about 85% efficient in transferring
power. However, calibration of the resulting system would determine
its efficiency within the range of expected hydraulic flow rates. A poor
man's calibration would be to test tractors that have published standard
PTO outputs. Also, don't forget that comparing PTO outputs before
and after modifications would still result in a good measure of the output
CHANGE.