I tried out the dyno feature. It seemed like it would be too high. I have the Cobb inlet and SF using stage 1. It shows something like 315HP and 365TQ. Could this be close to be correct?

Also I just used the weight settings that were in the AP. 3450 or something like that.

 

No.. That is much too high.

... Or too low if its Flywheel HP haha

 

the car weighs more than that.. what i did was drove on to a weigh scale with me in the car then typed it in to the ap. went for a run and it was like 260-280hp for a stock stage 1 mr

 

It must really be off. I did another run after that and raised the weight up and it just read higher haha. When I looked up the weight in the manual I tried out the gross weight which is like 4000 some lbs. After that it read like 500+HP and 600+ TQ lol.

I will try another run at the curb weight of 3517 for the GSR. I was hoping it would be more accurate. I will post up the new results. It will probably be next weekend before I get a chance to do it again. Thanks for the responses.

 

Higher weight while maintaining the same speed would raise the HP, not lower it.

 

inclines & declines seem to effect the numbers quite a bit too.

i'm not sure about the cobb numbers, but i find Virtual Dyno to be a valuable tool when it's used to track changes.
ie, install a part or tweeking your tune. go make a run on the same stretch of road in similar temperature conditions and you should be able to get a pretty accurate look at the relative HP difference.

 

All it is doing is seeing how fast you accelerate. It is then doing math based on what you gave it to determine torque/hp. If you do a run down a hill, you'll accelerate faster and the numbers will skew up. If you do a run up hill you will accelerate slower and the numbers will skew down. Same for putting in a higher/lower than actual weight for the car. It's only as accurate as the data you provide it. If you said your car weighed 10 tons, put it on jack stands and floored it, you'd probably get 100000hp or something, lol.

 

Exactly, it's just using basic math and physics. Read the following. http://www.motoiq.com/magazine_artic...-datalogs.aspx

Throw in a headwind, tailwind, uphill, downhill, weight difference, it'll all skew the readings.

Keep in mind that this is just a tool, just like a dyno. Keep the variables to a minimum and it should be repeatable.

 

This weekend I will give it a try and see what I can get to repeat. The road is really straight. I will let you guys know what I come up with. What numbers have you guys got with similar mods.

 

It wasn't a higher weight.. i drove on to a weigh scale and used the Exact weight of the car with me in it. then used the cobb ap to evaluate the estimated hp..

 

Change the dyno. Default is dynojet with CF of 1.09. The more accurate VD's have been done with CF 1.01. Go to options then change the dyno to custom and type in 1.01. Then fill out the SAE info of baro press and temp(can google the info). You will probably see the hp drop 20+hp/tq with these changes and should more accuratley reflet actual dynojet numbers you would get.

 

Im running stage 1 AEM 91 - AEM intake and HKS dual exit on my X and unsure of hp/tq numbers. I had the feature on Dynojet however was told to change it to Mustang Dyno, when doing so the numbers hange quite a bit...anyone know if VD should be considered accurate at all?

 

yes VD is accurate when you use a very smooth road to do your pull on, and log the minimum requirements. don't log injector duty cycle, fuel trims, or anything like that when creating logs to check for your power levels.

TPS, RPM, afr, boost, are all you really need to tick if using evoscan or something similar.

i have a dozen real dyno vs vd graphs that show its very close. it can be way off though as well, so be careful on the road you use. make sure its nice and smooth and flat.

read this thread for more info regarding vd https://www.evolutionm.net/forums/ev...-properly.html

 

What you need to do to make it accurate is....

-find a flat surface
-enter correct weight
-enter correct size tires
-enter correct air temp.

 

Like VDR, it can be somewhat accurate in perfect conditions if you input the variables accurately, but will never be real dyno numbers. It's a decent comparison tool to track your progress though.