I present to you Brad Barnhill's Virtual Dyno, [URL="http://www.bradbarnhill.com/projects/VirtualDyno/"]http://www.bradbarnhill.com/projects/VirtualDyno/[/URL] Yes there is no definition for our cars but making one is quite easy (you just need to edit the xml document in the programs directory to add the car, once you open it should be self explanatory) I made one for the cavy. You also need to edit your csv file from hptuners (basically just take the time, rpm, and tps columns and copy them into a new file). You also need to make these settings (in the options menu)



and then make a spread sheet that looks like this and save it as a .csv file



Then you can get a graph that looks like this.



Then increase your smoothing to make it look like a dyno graph should.



Pretty nice. And I think it reads high by a good bit of power. Let me know if you want to compare it to your VD or to any real graphs.


1994 Saturn SL2 Home Coming Edition: backup car
2002 Chevy Cavalier LS Sport Coupe: In a Junk Yard
1995 Mazda Miata R-package Class=STR
Sponsored by: Kronos Performance

WPI Class of '12 Mechanical Engineering
WPI SAE Risk and Sustainability Management Officer

That's sweet dude!! I love the virtual/desktop dynos mostly because they give a "shape" of the curve, even if the absolute numbers are off. They are just fun to play with.

We Megasquirt guys have MegaLogViewer, which can do pretty much the same thing. Your issue is probably somewhere in the engine speed to wheel speed relationship. I know you have the FDR and tire height, but did you provide a gear ratio and/or was this an automatic? In any case, there are a number of things that are inherently inaccurate about these "dynos" anyways. If you have an auto, there are problems associated with TCC lockup, there is a coefficient of drag that affects acceleration, you assume a perfectly level surface/street, etc. I will admit, though, they are fun to play around with.




I have no signiture

Yes I provided the gear ratio. If I could attach stuff I'd attach the xml document that defines all the pre-set cars to which I added a cavalier with a getrag f23. My issue is that I set it up for 205/55R16 tires and I did this run on 195/60R16 tires (my winters) BUT when I correct that tire diameter it makes the horse power go up. This is also using the dynojet correction factor, with the mustang dyno correction factor it looks much closer to what I expect I'm making like 215ish.


1994 Saturn SL2 Home Coming Edition: backup car
2002 Chevy Cavalier LS Sport Coupe: In a Junk Yard
1995 Mazda Miata R-package Class=STR
Sponsored by: Kronos Performance

WPI Class of '12 Mechanical Engineering
WPI SAE Risk and Sustainability Management Officer

Id be interested in supporting these vehicles. If I could get some information on them in the following format I can support them in future versions.

Also Id like to support HP Tuner Logs could someone send me a few? If so my email address is bradbarnhill at hotmail com

Car info format:

<CarMake>Subaru</CarMake>
<CarModel>Legacy 2.5i SE 07 (auto)</CarModel>
<Weight>3325</Weight>
<TransGear3>1.000</TransGear3>
<TransGear4>0.694</TransGear4>
<FinalGearRatio>4.111</FinalGearRatio>
<DragCoefficient>0.33</DragCoefficient>
<FrontalArea>22.00</FrontalArea>
<TireDiameter>25.07</TireDiameter>


Thanks,

Only thing I dont have is an exact weight.


1994 Saturn SL2 Home Coming Edition: backup car
2002 Chevy Cavalier LS Sport Coupe: In a Junk Yard
1995 Mazda Miata R-package Class=STR
Sponsored by: Kronos Performance

WPI Class of '12 Mechanical Engineering
WPI SAE Risk and Sustainability Management Officer

Leafy wrote:Only thing I dont have is an exact weight.

car weight?

mine is an 04 eco 5spd and weighed 2680 last I checked...

Last time I had the silver 04 lss on the scale it was 26xx

Damn so my guess of 2600 pounds with/driver was actually pretty good. Which is pretty scary considering that subie guys claim this dyno is pretty damn close... and well look at my numbers and think about my stock rods.


1994 Saturn SL2 Home Coming Edition: backup car
2002 Chevy Cavalier LS Sport Coupe: In a Junk Yard
1995 Mazda Miata R-package Class=STR
Sponsored by: Kronos Performance

WPI Class of '12 Mechanical Engineering
WPI SAE Risk and Sustainability Management Officer

My 99 Fully loaded auto Z24, with a full tank of gas, weighed in at exactly 3000lbs.




PRND321 Till I DIE
Old Motor: 160whp & 152ft/lbs, 1/4 Mile 15.4 @88.2
M45 + LD9 + 4T40-E, GO GO GO

While I will agree to a point with Whalesac about some of the assumptions, you have to keep in mind that actual dynos can be skewed too. So dont believe everything from your local dyno shop either. Ive seen some of their correction factors as high as 30% (1.30). So atleast this way you can save yourself some money when you want to see numbers. Also peak numbers are not what dynos are made for anyway. They are designed for giving you a baseline to tune from and then measuring after changes are made to see if what you did made a difference. So they are comparison tools.

Just my rant ... not that I am unrealistic and think that people dont use this for peak numbers either ...

Ohh yeah ... 1.0.8 was released yesterday ... enjoy guys!!!

1.1.0 was released on June 2nd. Just thought you should know.

1.1.1 was released to fix a few bugs in 1.1.0

Now that the app automatically checks for updates I can send out releases more often.

Im guessing interest in Virtual Dyno has faded on this forum (Im the only poster since Feb.) so Ill stop monitoring this thread now and if you need me you can find me on the HPTuner forums or the Evolutionm.net forums.

I just saw this now...this is cool!

Gonna use this for sure when I start tuning the new motor!

Also, let me see if I can dig up an old log of my car.

I dyno'd 169whp on the tune thats been in my car all year....if I can find an old log it should be a pretty good comparison.

Let me know how it turns out.