MoTeC Global Forum

Hi Guys,
I know this question is quite i2 based but its pretty tuning based, so...
Has anyone used MoTeC logging to approximate Dyno software?
Yes, I know dedicated dyno software is the best..and I'd be interested to hear of any good basic dyno software.

However, a customer has access to a good but basic Dyno and we also have access to MoTeC logging kit so I was looking a making up a basic rig to get started outputting some usful info but always worth asking if anyone approached this before.
Our aim is to log: Torque and Power Outputs from Dyno, RPM, Throttle, Eng Temp, Oil P, EGT and Lambda from a PLM.
I openly admit, I'm more race data based and not been on the engine tuning side for a couple of seasons!
J.

JayDee wrote:Hi Guys,
I know this question is quite i2 based but its pretty tuning based, so...
Has anyone used MoTeC logging to approximate Dyno software?
Yes, I know dedicated dyno software is the best..and I'd be interested to hear of any good basic dyno software.

However, a customer has access to a good but basic Dyno and we also have access to MoTeC logging kit so I was looking a making up a basic rig to get started outputting some usful info but always worth asking if anyone approached this before.
Our aim is to log: Torque and Power Outputs from Dyno, RPM, Throttle, Eng Temp, Oil P, EGT and Lambda from a PLM.
I openly admit, I'm more race data based and not been on the engine tuning side for a couple of seasons!
J.

Yes...
Torque is a force measurement.

On a car...
The acceleration is based upon the physics equation F=MA
One could:
1) use a strain gauge to measure a torque directly
or

2) use an accelerometer to measure acceleration
3 differentiate the wheel speed or position to get acceleration
And then compute F based on M & A

Power is either force through a distance, or the derivative of energy versus time.

If you have a dyno then the aerodynamics forces are non existent, and you measure the force with a strain gauge (i.e the Dynos one) or the dyno's power generation, which is the volts*amps of an eddy current brake..

On a car one might use dE/dt for both power as well as braking energy analysis.
You either do the maths in i2 or you use a .dll and have i2 interface with the .dll

If you need help I am a S/W engineer and physicist by trade and background.

Another way, which might be easier...
Export the data as a .cvs file and use MATLAB or something else like python and GNUplot, to take all the data and separate them into 'cells' and perform statistics on them. The first step is to separate the throttle transients to understand the steady-state, and to understand the throttle transients effects.

The main thing that the dyno offers is to be able to get the steady state tune done safely and quickly.

Especially on the road, there are a lot of cells that are difficult to get to at the trailing and light throttle that not really dyno friendly. Combining that with altitude and heat as well as emissions and economy needs, usually means that a road tune has a lot of complexity. Whereas race usually spends most time in the idle and WOT cells.
Gaining insight into where the road car spends its time, and acquiring that data makes a good case for in-situ data collection on the vehicle and post-facto analysis.

Hi, thanks for the reply, My description of this project is bit of a simplification, I'm happy with the engineering side of the dyno and its operation, pro's/cons of road/engine testing etc, however the dyno in question is usable but does not have a modern software interface such as I've been around when working with larger projects. My main interest is if anyone had fed raw dyno data into a motec logger and produced an reasonable approximation of typical dyno graphs. I know it can be done at a basic level but anyones first hand experience may highlight limitations to this approach. J.

You should be good to go. Just get stuck into it.

Is there not already a dynosim type software that works off .csv datalogs ?

Ive definitely heard of one, cant recall the exact name of it though

I was doing it for years with a vane vp930 that I converted to use a load cell and roller rpm signal

Used a adl to log all parameters required ...it worked great was so good to be able to overlay everything
Best thing is I do only MoTeC tunes so you just CAN bus all engine data to adl and also have Dyno data on same log and time lines

Only down sides were ..no automated ramps - only manual turning of the load knob...after a while you get very consistent but no as good as auto mode
Dyno was maxed at about 200 kW ...

Late last year I bought a Dyno pack hub Dyno ....it's great ....but I miss the ability to overlay every detail ....
I am looking at getting the data transmitted out of the Dyno pack to my adl ...not simple but it can be done

John P