I would like to build my own dyno for tunning. Here is what I think might work. I have a couple of road compacters that I would like to cut the drum off of. I would then couple the drum to a generator. I also might be able to drive a hydraulic pump and force oil through a small hole. The whole assembly would be buried and the car would sit on the drum and turn it over. Sure I would not know the true horspower( Maybe I could with the generator idea) What I would have is a way to judge when i start tunning the car. Could I just put a constant load on the drum and build a circuit to read the speed of the drum? Then I would Start tunning In say, 400 rpm increments. Then I would look for the smallest TPS value to maintain the drum speed. Slowly the fuel and spark would be changed and the results recorded.

Would It work? Building the dyno would not be hard to put together, but would my idea with the tps work?

 

the mechanical portion of a dyno is fairly straight forward, especially if your only goal is to only apply some load for tuning purposes. The technical part is the data aquisition system and software to do the calculations. For instance if you have a 2200 pound drum and accelerate it from x rpm to y rpm in z seconds you can calculate horsepower.

 

Thanks for the reply,
Do I need to calculate Horsepower? I just Thought I could maintain a constant load (drag) , Make changes in fuel and spark, Finnaly I would watch the Tps value or speed of the drum to monitor changes
I know there are easier ways , 1/4 mile times, But I dont think a 1/4 mile time can tell if the car is making more power at any one rpm. I hope this makes sense

 

I friggin love it! That's an awesome idea!

If you decide to do it, I'll be glad to help with the engineering calculations and software end when it gets down to it.

 

I wish I were closer. I can weld and would be happy to help with the construction of this project. When you finish it, would you please post pics and specs so I can do the same thing?

 

I measured the compacter rollers today It doesnt look like they are going to cut it, All of them are 40 inches wide and they vary in height so I could not weld two of them together. I think I might have something better, what about using supersingles, I know, it sounds like something you would find on a burger king menu. No, a supersingle is the front tire on some semi trucks, it is as wide as two tires, I have access to plenty of them with rims, hubs and axles. Using a rubber tire would offer more traction than using the steel drums off of the compacter. After measuring tire to tire with a differential off of the cement truck It might work using the semi differential and simply couple the generator to the differential.
Hi Craig,
What do you think would be the best way to measure the dyno? Generator, use the power generated for caculations. or count the revolutions of the tire and compare the number to the TPS. If I went with the counting the revolutions from the tire I could put the dyno under constant load and use the speed off the car for comparison. The high frequency ouput of the t56 would offer plenty of resoluton.


Hey Jeepguy53 Ill take plenty of pictures along the way. It will be a month before school lets out and I have the time to work on the project. What would you use as your rollers? Do you have access to semi Supersingle tires?


Thanks for the your help and input guys

 

Hmm after looking around the biggest generator I have only takes around 150 hp to run. The biggest hydraulic pump Off of a cement mixer truck only takes around 50 hp to run. I would not be able to put a very heavy load on the motor. An easy way to burn off horspower would be to use the supersingle tires on a semi trailer axle. the semi brakes would be used to apply a load to dyno. I know the brakes would last for a while as long as I did not get them so hot they glazed over. Here is the trick, I need to have a steady load on the engine. Craig , do you know a way to use the map sensor (engine Load) to control a circuit that would control the semi brakes? The brakes are air operated so the circuit would have to slowly increase the pressure going to the brakes as they slowly fade.

 

You should be able to put together a quick circuit to provide a 4-20mA output, which can be used to drive an I/P converter which will in turn regulate a 20psig supply down to 3-15psig, variable and proportional to the signal. So, you put in 0-5v and get out 3-15psig. I think they have some broader range dealies too if you need more pressure.


For the rotational resolution, I'd think you would want some sort of pulse wheel or something that gives a frequency and you can use that to determine rotational speed and do all your math on that.

 

Thanks Craig,

What do you think about using the VSS or sender in the tranny for the rotational speed? Should be the same as measuring the speed of the dyno when its all tied together

 

Yeah, that could work fine. It'll vary depending on gear ratio, car type, etc though.

 

Is this circuit linear? I know the idea is to maintain a constant load so changes to fuel and spark can be recorded regardless of load. If I used the brake Idea it would probably work well for a couple of minutes ( load would be constant). After a couple of minutes the drum would start to build heat. When the drum expanded, more air would be required to push the brake pads against the drum with the same force. A simple regulator would do this, set it at 30 pounds and it would add more air as the drum expanded. One thing a standard regulator could not do is make up for loss of friction when heat is built. It would require more and more pounds of air to maintain load. This would be the tricky part I dont think a linear circuit would work. First the circuit would monitor the load of the engine (0-5) volts, user adjustable for various loads. As the brakes get hot the circuit must add a little more air to bring the load back to the correct load (0-5 volts). Again it would contiue to monitor the input and add air, however it will take more and more pounds of air to manitain the same load. ( In real life , Most Semi trucks have a gauge that tells how much air is being applied to the brakes down a long hill If the proper gearing is not used the brakes get hot and it takes more and more pounds of air to hold the truck back)
I really think using the large brakes would be the ticket for a good constant load. The amount of time that it would work before getting hot would depend on the load. light throttle
tuning would take longer to get the drums hot enough to fade. To tune WOT, put the car in a higher gear such as 1-1. Two 16 inch drum semi brakes would last for a while before they got hot and the tuning would have to be stopped to advoid glazing the brakes.
Thanks

 

Here's a homemade dyno used on motorcycles. Maybe you can get some ideas.

http://pages.quicksilver.net.nz/geof.../DIY_dyno.html

 

Thanks John, I couldent tell at first how he was measuring the output of the motorcyles. Looks like it is an inertia dyno that measures how long it takes the drum to speed up. Good setup to tune for 1/4 mile performance. If I cant build a load Dyno I would like to build a dyno similar to this one.

Craig, I have another question, Idea for you to look at.
Like the above posts. Use the semitrailor axle with supersingles. Again use the semibrakes to apply load. Here is the difference, instead of making a circuit to watch engine load And try to keep the brake pressure constant, Use a load cell. The trailor axle tires and brakes are all one assembly. This whole assemply would be held up by two large bearings so it can twist. An arm would be welded off of the axle assembly attached to a load cell. This load cell would do two things, first keep the axle from twisting in the bearings, Second it would give a output linear to the amount of brake force. I could use a circuit like the one you described above , only i would use the loadcell as the engine load reference. Brakefade would not be an issue . More brake fade=a lower outputvalue on the loadcell. The circuit would recognize the lower output and increase the pressue of the brakes until the Loadcell is happy

 

What would it take to make an adustable 0-6.5 volt switch? I found a loadcell that puts out 0-6.5 volts
YOU ARE BIDDING ON A NEW, COMTROL LOAD CELL, TYPE K DC LVDT WITH CONNECTOR.1200LB MAX LOAD. INPUT IS 6-30 VDC, OUTPUT IS 0.5-6.5 VOLTS DC (NOMINAL, OPEN CIRCUIT). OUTPUT IMPEDENCE IS 2.5K OHMS. CURRENT CONSUMPTION IS 40 mA, RECOMMENDED LOAD IS 100 K OHMS OR GREATER, BUYER TO ADD $25 FOR S/H TO THE LOWER 48 STATES.

If I could build an adjustable switch 0-6.5 volts I would control a solenoid that would apply more air to the brakes.

Ive got this thing figured Out Ill hurry and get some pics up.

 

I have an idea for a constant load: dynamic braking. It's used in many apps. in industrial and other settings as well. If you don't know what it is, it is when, after power is removed from it, an electric motor's windings are run through a loading circuit, such as a bank of big resistors or inductors. This slows the motor down much quicker when you need to stop it sooner or when you have lots of inertia to overcome. Basically, the motor becomes a loaded generator. And since every motor is a generator, well there ya go.

If you could find, say, a big-*** industrial electric motor on the surplus market for cheap (not unusual) it could possibly be made to work. Of course, you would not need to provide any power to the motor for this to work. Just connect the drum to the motor shaft via a nice wide, flat cog belt, conjure up some loading system and voila. Possibly, you may be able to find an industrial manufacturing machine surplus, complete with its big-*** motor and dynamic braking system intact, that someone may be willing to part out.

Just a thought. Hey, it's late man.........

 

Hi Gents,
I don’t want to spoil your fun, but I use an Accelerometer (Road Dyno) device for this purpose.
You can get you power and moment and other details from the device.
It is a device (4” x 2”) that you hold on your dash and you make several runs and after that you connect to your PC or Laptop to get the figures.
Actual you measure the acceleration (G forces) or deceleration (braking) but you also measure the corner (G forces) good fro track tuning of tires etc.
You can see this baby at:
http://www.roadtune.co.uk/dynoplus.shtml
I know that there is a USA representative.

See one of my results of My DynoPlus. (100 UK pound)

Regards,
Cobra289

 

Well, yea, but I think he's looking for something that he can run in his shop so he doesn't have to risk life and limb getting his tune right. You know, a static load so that he can maintain it for extended periods without having to slow down for granny, or dodge a pothole. Something that removes road hazard interruptions from the equation. That's my impression anyway.

 

Well, in that case, he could build what would essentially amount to a test rack. Get some heavy-duty conveyor belt rollers and bearings. Weld up a frame of sorts that he could drive the car onto that would keep the vehicle elevated a bit off the ground (6 inches or less is what I am envisioning). He could use some sort of friction brake on the rollers to simulate a load on the vehicle. I might even go so far as to incorporate some sort of chain or other secirung method to prevent driving the vehicle off the test rack when it under a simulated 100-mph run...that way he wouldn't drive the car through a wall.

 

Jeepguy553, I didnt even think about using rollers for a test track. How long to you envision the tracks 2 feet? That would be great for a low profile portable setup.

LnealZ28

Any idea how many horses can be burnt off using dynamic braking? I have a 50 horse electric motor. I dont know if it can burn off more horses than it produce as a motor, Eddy dynos work kind of like this, the car trys to turn a motor backwards that as power is increased to the motor. From what Ive read they are built with special cooling provisions to get rid of the heat. What would be nice is to find a waterbrake but im sure they are costly.

 

Actually, you could weld up a frame of sorts that would allow you to drive up a small ramp onto the test rack. Have the thing fabbed up so that the tracks run on each side with a pair of rollers under each tire. in the front, you could make a sort of "pit" for the front tires to sit in with a wedge at the front and rear to act as a sort of wheel chock to keep the vehicle from moving. The two tracks should at least be made such that they are as far apart as your axle is wide from WMS to WMS...in other words, the rack could be made such that it is the same width as your track width. A friction brake or something of the sort on each pair of rollers would apply a load to the tires and therefore on to the drivetrain and engine. You could set the friction brake up in such a manner as to have it variable to simulate different load conditions.

 

I just need a circuit that can be sense a voltage. It needs to be variable in small increments. It will act as a switch point for a relay. So here is how it works. The adjustable voltage is set at a value. A circuit to run a solenoid applys air to the truck brakes. The loadcell reads the torque and when it gets to the preset value it turns off the solenoid. When the brakes fade and the torque starts to drop the loadcell value falls below the preset point . more air is automaticly put into the truck brakes to maintain constant torque.
Ill use my wideband and rpm convertor to read rpms. If I know the rpms of the motor and the torque of the loadcell I should be able to calculate horsepower. It would also be easy with the rpm convertor to read the loadcell and setup a graph that shows acutal torque.

 

If that load cell and torque sensor is anything like I am thinking it is, you better have some $$$. The ones we used in the Navy to calibrate torque wrenches were EXPEN$IVE. They weren't anymore than about 4 inches in diameter, but they were VERY precise and could measure down to 1/100 of an inch-pound or better.
It IS a cool idea. Let's see if you can pull it off. It would REALLY be cool for tuning your ECM in the garage.

 

Hi Jeepguy 553

I know loadcells can be expensive, We have a cement silo that can weigh a 100,000 pound silo in 10 pound increments. We have the whole silo on 4 loadcells. An bucket system inside of the silo dumps cement powder into the cement truck. It works great because we are always within 10 pounds of the required cement powder and we know how much powder is left in the silo. I went to ebay and sure enough there are loadcells. some of them that I think would work are less than 200. The loadcell requirments could vary up to 5000 lbs. I would just have to adjust the loadcell arm. Example, car makes 400 lbs of torque, tranny is in 1-1 gear, rearend is 4.10 ratio. Car tires are about half of truck tires 2-1

The torque is now multiplied 6 times. so I need a loadcell that can handle 2500 lbs with a 1 foot loadcell arm. 1250 lbs with a 2 foot arm.

 

I don't know off hand but I have a friend who is an electrical engineer and I will talk to him about it. The power would have to be dissipated somewhere. The more the load on the windings and the faster the RPMs are the greater the load presented by the motor would be.

EDIT: Just remembered that Craig Moates may be able to help with calcs, if you were interested in pursuing this approach.

 

Gotcha, Austin. Good idea. The load cells we used in the Navy were probably far and away more than you are gonna use. These things were about $8000 each (I think). They were some kind of piezoelectric cell with a socket in the middle for the proper size drive (1/4", 3/8", 1/2"). The whole machine would move the torque wrench until the operator told it to stop. Usually at a preset value. We could then calibrate the wrench to read what the loadcell said it was supposed to read.

 

Not all eletric motors are configured so that they can be a generator too. Been a long time since I had my theory classes so I can't remember the correct terminology to tell you what to ask for. But that wouldn't be hard to find out. AC motors are designed to run at specific rpms as far as cooling goes. You'd need to monitor the temps to prevent burning the windings. The motor efficiency is stamped on the label plate. Just divide to the hp # by the efficiency to get the load. The normal range is 0.8 to 0.95. 50hp is only good for part throttle tuning. Not to mention you need a place to send all of that electricity. Load banks aren't cheap.

A hydraulic setup would be the smallest foot print, but with your small pump/motors, you'd need to put several in parallel to get the required HP. It would require a drive system strong enough for all of them. And make a cooling system.

The load cell actually seems to be the easiest. If you use the switching method for pneumatic control. Your engine load may end up looking like a saw tooth pattern. You'd get a step change in load every time the air was increased. You may be able to set the switch points close enough togethor to get a relatively stable brake load. Depends on how fast the shoes fade.

There are 3-15 psi and 6 to 30 psi current to pneumatic converters. There are also 0-5vdc to pneu. converters that aren't as common. You can also convert 0-5vdc to 4-20ma. A cheap new 3-15 is about $300. Used prices will vary to close to nothing. 6-30 and the voltage to pneum. converters are less common. Depends on where you live. What kind of industy is near you. A cheap controller is about $300 new. They can usually be configured for a current or voltage input and a current or voltage output. So you'd just hook the cell straight to the controller and the output to the I/p converter. The output of the I/p to the control side of the air brakes or to an air cylinder to increase the leverage on the air brake controls.

I would imagine that someone could design and build you a card to do the electronics for the switching or the current control side for a lot cheaper. As long as the labor is free. The switching circuit should be really simple I would think. Similar to a DIYWB.

If you want an actual dyno instead of a variable load cell, a single heavy roller with a speed sensor is a better way to go.
If you can fill the roller with water, it dramatically increases the load. I never did much rotational physics calcs so I remember next to nothing about them. Craig can probably do them real quick if you give him the diameter, drum wt, and water volume.
And any ratio changes between the vehicle and drum.
For accuracy, you'd need to cal your dyno to another one with the same car weather etc.

 

Well what I meant was that motors produce back EMF which is reflected back into the power source. But yea, just any old motor may not work properly for this, which is why I suggested that he find a setup with the DB system intact. Load cells could very well be the practical answer.

 

Thanks for the great Info guys,

I think the shoes would last for a while without fade. I thought of another way to do the test last night. Put the car in 1-1 gear and slowly bring up the rpms, At the same time bring up the psi to the dyno brake. The brakes will be applied so the car can be WOT at say 5000-6000 rpm. slowly increase the pressure to the brakes and remain at WOT. The motor will start to slow down because of the load. Engine RPM, Loadcell Torque, wideband AFR, and Tps will be logged. Next make fuel/spark changes and do the run again. At a given TPS value if the car can produce the same torque number on the loadcell at a higher rpm then power was increased. This way the brakes would not have time to fade and I would not need a switch to maintain load. I would only need to convert the loadcell to 0-5 volts so I can log the output

 

You might want to go over to Land and Sea, they are the folks that build the dynomite dyno's they also specialize in off the wall dyno's like for snowmobiles, R/C cars, and go carts. They also sell individula parts, as well as some really nice software that will map everything out for you. Check them out.

http://www.land-and-sea.com/

This particular page has some cool stuff on it.
http://www.land-and-sea.com/data-acq...ynamometer.htm

 

Will super singles last at 100+?
Probably need a new car if they come apart.
Can I watch a 6k run? From a safe distance


Not trying to start anything here...

Generators produce counter EMF. Since they are the power source, it just shows up as less output.

Most of my schooling wasn't EE related, but I fail to see what counter EMF has to do with a home dyno.
If the motor doesn't have brushes, then you can't make it into a generator. No way to apply a mag field to the rotor. Is what I meant. There are technical terms for all this that I've forgotten.
I just go and get the label plate data and order a new one. Never have time to look any further.

 

That is a good point, I would think they would last Ok because they dont have a lot of load. The fastest I have tested them is 75 mph on the front of a concrete truck.



One of my problems right now is getting some 5 inch bearings to hold the axle. $$$

 

Thought of something else. The size ratio of my car tires to the super single tires is around 2-1 . Speed will be cut in half. If I do a run in 4th gear 1-1, with a 4.10 rear the car will run around 120 mph. The supersingle tires will only run 60 mph. Sure a supersingle can still blow but the consequences are lower than blowing a tire on a 75,000 pound truck.
Thanks for your input that is something I probably would have overlooked.

Also thanks BMmonteSS for the website link, great Info

 

The way I see, the axle speed is cut in half. The tire OD's cover the same distance. So are at the same speed.

You might try putting bearings in the walking bar axle end. Just make a slotted end link for the top to slide in but still be secured.

 

I want to pull this thread out again, I have more time with the summer break to get serious with the dyno. I thought of another idea that I would like some feedback on. What if the loadcell was in the cable/chain that held the car back? The axle assembly would no longer be on a pivot it would be secured. As the brakes were applied for the dyno axle the car would pull harder and harder on the chains that held it back and the inline load cell.

 

Not sure about that. I did see some stuff on dyno in a magazine recently. You might want to check that out. Wish I had some more info for ya. DIY-DYNO would be a great project. :hail:

 

rather then a frictional brake that wears out, why not just do it like a real dyno.

a waterbrake..

the energy is used to heat the water(water can hold ALOT of energy), and then the water goes thru a cooling place and then back into the tank. the larger the tank, the more BTUs it can absorb.... meaning, the radiator or whatever is dissipating the waters heat doesnt have to be huge. you just cant run it forever...


i realize that you want to use the truck axle setup because its together and appears easier, but i doubt it will end up doing everything you want it to.

 

The artice I read did show several shots of a dynojet(I think that was the company). It uses a truck axle.Not sure about the brakes...

 

I researched the waterbrake Idea and I agree it is better than a friction brake but I cannot easily find a waterbrake. I have access to semi truck axles and I think the brake would last Ok

 

for those of you who have actually had experince with a dyno how are the dyno runs done. Do they maintain load or rpm? Do you think that this would work? First bring the rpms of the car up and at the same time apply the dyno until the car sits at 6000 rpm with enough load so it will not overspeed. Next, while continuing to hold the throttle down, apply more load. load will contiue to be increased and rpms will drop until say 1000 rpm. both the torque and rpm will be recorded and graphed. Next make changes to the bin and try the dyno run again to see if the changes helped. If the engine has a higher rpm for the same load then the changes are in the right direction.
What do you think would it work? I also thought about using the cruise control to maintain rpm. Then the load could be applied until the car could not hold the same rpm As soon as the rpm drops then the car is at its max.
Also does the car need to be dynoed for different throttle positons?
Thanks for all of your input

 

How are you going to ensure that the load is consistant? With a friction device, it will change significantly with temperature. If you were to do 2 runs back to back, the second would be a different load, due to heat. Just think abou thow your cars brakes work. They work better after getting a little heat in them, but too much heat will make them drop off.....

 

The second run might require more air in the semi brakes to get the same load, but it is not the air or force of the brakes that will be recorded. the load on the engine and the rpm will be used for comparisons. It might take more air to reach the load but it can still be held at a constant.

 

I WAS going to stay out of this as I had a similar idea. But in the interest of DIY this is what I was thinking. Use a thirdgen drum rear (same width, just add some old wide tires) setup like a floating rear (like your load cell idea) come up with a way to add some breaking to the drive shaft and use two master cylinders to control the breaks. One would be used to “set” the load, the other would be attached to the torque arm and “adjust” the breaks dependant on the “twist” of the rear. A lot like the hydraulic breaks on a slip neck trailer. The more the trailer slides forward the more pressure on the master cylinder. The more the torque arm moves down the more pressure on the second MC. So you would have two breaking systems; one on the drum breaks on the rear, one on the breaks that where “added” to the drive shaft output (input). You would use one to “set” the load and one would “control” it. There would need to be some kind of spring on the torque arm and probably a shock of some kind (was thinking motorcycle shock as I have half a dossen) to keep the assembly for oscillating.

This would be good only for short runs (a minute or so). This should be long enough to get a TPS reading at a given load and adjust timing and what not as needed. I was NOT thinking of this as a way to measure HP/TRK, just a way to control the load on the engine at a given RPM/LOAD. It would NEED a cool down time in-between runs, but this when you would be changing things and burning a new chip.

Was thinking it would be better to load the drive shaft input (output) and use the drum breaks to “control” the load.

Any thoughts on this? Anything you can use?

Legal notice: I did not post this to start “the 10 bolt rear is week” argument.

 

I figured it would be easy to do. Just need a wheel that's similar in weight to the car. Then take the car to the correct gear and go wot. While doing this measure the time it takes to move the weight from like 2000rpms to redline(engine rpm). Using a magnetic or optical device to sense the weight/roller's rate of acceleration is all that would be needed. Well...that graphed against time and engine rpm. Just need the brake to slow the wheel down afterwards. It would seem that any brake would work.


Why use a device to simulate load when weight should work alone,yes?

 

Needaz, I think we are thinking a lot along the same lines. the thing I really liked in your idea was using mechanical means to maitain a constant force. I was trying to think of a way to maintain force usings sensors and it was getting too complex. Another thing I think might work is to controll the rpms using the load. As more load was applied the rpms would drop. At the end take the torque Times the rpm and divide it by 5252 to get hp.

11sorbust, Your idea would work great to tune acceleration runs, I want to be able to maitain a constant load so I think I will still have to use a brake. A easy way to try the inertia dyno would be to calculate the weight of the semi tires/rims/and hubs. the brakes would be backed off and the assembly would be used as the weight,

Thanks guys for your input, alot of great ideas comeing from this thread. here is a link where I will order my loadcell and signal conditioner. The loadcell is 130 and the conditioner is 80 dollars. I should be able to put together the dyno for under 250
http://www.a1scalesource.com/comp01.htm

 

11sORbust, your idea would be great for tuning WOT, we’re talking about being able to do WOT and part throttle easily in your driveway.

AustinT, my thought was to try and keep things simple as possible. I was thinking of using a pump of some kind off of the drive shaft. First thought was a large water pump pumping into a small tank (to help even out the pressure) then through a screw valve of some kind (with a good range of adjustment) then right back into the pump. It would take a BIG inefficient pump and some high-pressure hose and fittings. I think with a big enough pump and tank this would be all that was needed, using the breaks may not be necessary. But it would take a pretty hefty amount of water. But I don’t have a pump so I tried to come up with some other ways.
“Another thing I think might work is to controll the rpms using the load. “ But then you’re getting away from keeping a constant load. My thought was to maintain a consistent load at a given RPM, then adjust timing and A/F so it takes the minimum amount of TPS to maintain that RPM under that load. Really making it E-Z to dial in every spot. It would even help out with the PE and AE tables. I haven’t done much tuning, but it seems that if this could be done on the cheep it would be a great help.
Those hydraulic pumps that you mentioned taking 50HP to run. Is that 50HP to run at normal pressure or 50HP MAX. If it’s 50HP at a normal pressure I wander how high you can push them before they pop?

Now if I had some spare time and money……….

 

Maybe an irrigation pump, water truck transfer pump, fire fighting equipment (on truck or in building) pumps. If you could track down a cheep used takeoff pump from a fire fighting rig that could work, some of the big ones take something like 300 HP to run under full load (and can empty a small pond in a couple of minutes). Something like that in a closed loop with a way to control the output pressure could work. Or even in a open loop, got a swimming pool?
Time and money…….

 

Part throttle stuff? That's a different story. It'll be near impossible to simulate the load. It changes with each gear. Part throttle stuff should be done on the street,IMO. There is no risk to limb or life logging part throttle data(usually). It's not like making 100mph+ runs on the street. I thought you was using this for WOT. Really it just takes a couple of times logging to get the part throttle stuff good. Besides, simulations have small bearing on real world results. Think how much stuff you'll have to do to get a real comparison to the street. One thing is that you'll have to use something to simulate wind. And that device will have to match the wind speed to mph. Not to mention other things that will be needed to compare to road driving..That's if you really want to totally simulate the part throttle stuff. Imagine how much work it'll take to sim a hill. Each car is going to have different load values for the same hill,generally. Then you have a million different types of hills. I like to tune the car for the conditions it'll be used in. That means logging data where the car is going to get used,more or less. City driving will require a different programming than a country driven car.....


Good luck on the project though. I'm not trying to say it wouldn't work, anything is possible. I just think it'll be really hard to honestly simulate the load for different conditions and cars. If you do get the project up and running then you should take pics and make a diy page.

 

Correct me if I’m wrong (I’m new at this) but wouldn’t the engine “see” a strong head wind as an increase in load and a big hill a large increase in load? So we should be able to simulate a hill by an increase in load. The transition maybe a little harder but isn’t it, in it’s simplest terms, a load on the engine? I know this doesn’t take gearing into consideration, but this could be done in 1:1, or even in first, if you could load down the engine enough?
What em I miss’n?
Would it be beneficial to ruff things in using this then if needed fine tune the odd ball stuff from data logs?

 

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<p>Here are a few pics of the progress of the Dyno.</p>
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