RomRaider

The Dyno/ET functionality has been integrated into the main branch of RomRaider as of the RC6 release. So if you'd like to try this feature out just install 0.5.3Beta RC6

Dale, did you manage to get the quartermile calc part working correctly?

I beleive so, no one has reported otherwise.

This is great. Roughly how accurate are the outputs compared to a rolling road? Has anyone tried?

Dynometers are only as accurate as the operator and dynometer allows - that is, most are very inaccurate due to the operator or the dynometer itself

whp calculated from Airboy's spreadsheet and now in RR itself (cheers Dale) will be much more realistic - they have been shown to closely match estimated whp calculated from 1/4 mile trap mph.

The results from Airboy's spreadsheet and now in RR are similar to Mustang/Mainline dyno results.

Leslie

What's an ideal test road for dyno? Just a flat road that's smooth all out?

Actually, once calibrated the actual Dynamometer (there are different types) is very accurate device per say. Also a “dyno” measures “torque” and via a math equation, you get WHP.

But as mentioned the operator is varying factor, but not very much.
What is more of a factor in measuring your actual power (be it WHP or HP at the crank) are these factors.
Your numbers will be effected even if keeping the same gas oct. on the same tank full.
Elevation (above sea level),
Humidity,
Air Temperature,
Your actual engine temp,
Type of oil used in engine, trany and diff,
Type of tyres,
Air pressure in tyres,
The way the car is strapped down on the Dyno <- this is a big one,
And yes the operator, but that is negligible.
And how do I know, well, we had 2 4Wheel Dyno. Your typical inertia mass dyno, and a Hydraulic Load (also called absorption) dyno. One weekend we were bored, so we did test on the same car ( a stock NA 2.5RS, as that car will give as consistent measurement as you can achieve).
As long as the car was never removed from the dyno (as in unstrapped and move then put back on) and nothing was changed, the numbers varied a bit during the whole days tests. If I remember correctly, it was about this time of the year, we did 3 pulls every hour (then averaged them out). I do not recall exactly by how much the difference was, but it was in the neighborhood of about 10%.
Now once we unstrapped the car, changed tyres, and oil, WOW, big difference in numbers !
Later that week, I took the same car to 3 other Dyno’s in town, and I tell you all, you should see the difference, talking 20%+ from one place to another.
What we can learn from this is few things:
Never trust a dyno – it just gives you a figure. (I know this conflicts my statement that a dyno is accurate, and it is, but it all of the other surrounding factors that make the resulting HP number erroneous)
Dyno “loads” your car differently than actual road will. So a car will not necessarily make the same HP on the road. (this mostly applies to turbo cars)
Driver makes the biggest difference !!!! cannot repeat that too many times.

There have been people caught modifying their dyno’s to show higher HP numbers then they should, we all know the reason for that.

Now what a dyno is great for, is one thing and one thing only (IMHO). No matter how inaccurate it is, it will give you an idea of how your motor is doing before any mods/tuning, and after mods and tuning. And using it for trouble shooting.

So don’t look or be concerned with the “final” high number, care more about what you had before and after.

I tried the dyno out and it was really cool, definitely a great tuning tool. One thing I noticed though, im not sure how the horsepower or torque is calculated in the program but im assuming they are calculated separately because the horsepower and torque curve are always supposed to cross at 5252rpm and when I used it they crossed at about 4500rpm???

If they were plotted on the same scale they would. Each HP & TQ have their own scale, the curve line colour and scale title colour are used to relate them.

Also note there is no correction factor to allow relating results of one run to another of a different day when the temperature, humidity and pressure are quite different. I have to add that...

Oh ok, I thought they were on the same scale. I must not have noticed that.

for some reason, the dyno was not working right for me. i set the rpm window to around 3k-6k, set the car and everything, and when i clicked record and went WOT, nothing would show up on the graph. i didnt check but maybe im not getting 100% tps... is the dyno looking for a minimum tps? also do i need to enable logging of certain parameters? or should it just work? i dont think it makes any difference but i was using an apv1 serial cable to log. i was able to connect and see live data so i wouldnt think that would be an issue.

There's no need to set any parameters. Select your car, press the record and any WOT data will be gathered. So yes you need a working TPS which gives >98% to use the Dyno tab.
You can log RPM and Throttle Angle, save it and then later open up the log on the Dyno tab too.

could you guys make it so that you can get an overlay of "total ignition timing" and maybe even "engine load" on the dyno graph??? I think that would help greatly with the tuning process

You might as well just use Airboy's spreadsheet then...

I took 2 wot runs today. Both vary, see png in zip file attached.

261.2 hp with 321 torque for the first.
388.7 hp with 388.2 torque for the second.

Graph of the run vary as well.