JerryS4

A friend suggested that I try an iPhone app that does a very good job of tracking a cars power and acceleration using the latest sensors found in smart phones. Having read some reviews and watching the video, I purchased the Dynolicious Fusion app for $9.99 for my iPhone 5. It uses GPS, accelerameters and pretty good software to record and analyze the stats. Here is a video:


Anyway, after a few runs, my modified A7 with the Stasis ECU tune, quad exhaust and Injen intake came it at:

0-60 MPH = 4.75 seconds
Max HP = 375 hp
Fastest 1/4 mile = 13.34 sec

I am pretty pleased with the results of both the A7 and the software. This was with a 3/4 full tank so I will do again when close to empty. Anyone else have any experience with this app?

feralc

How much drivetrain loss did you put? It is a Quattro system with automatic transmission, less than 20% is not realistic.

JerryS4

Here is what Dynalicious Fusion's capabilities are from their web site:
http://www.bunsentech.com/products/fusion/index.php

Acceleration Tests (in 10MPH increments)
1/4 Mile Elapsed Time
1/4 Trap Speed
Elapsed Time and Trap Speed
Lateral G’s (current and peak)
Braking G’s (current and peak)
Wheel Horsepower
Friction Circle

I just plug in the model, car's weight, driver's & any cargo weight, and fuel tank contents. The software does the rest. Not sure if the HP is at crank or wheel but I suspect it is the net power to the wheels. I mainly wanted to see the acceleration and have the power to pass or accelerate with a few passengers. Did not do the skidpad test yet and likely never will since the A7 is not a slalom racer. Here is my second run graphic picture where the time was best but the HP was a bit lower:

feralc

you have it right there wheel horsepower, if you could not put drive train loss then it is wheel horsepower, a more accurate test will be weighing the car in one of those truck scales (they charge you 10 dlls) instead of the published ones, you never know the real weight until you actually weigh it, that what I did when I used the app in my former Mercedes.

aquarian

Very nice... Which Drive Select mode did you use for the runs?

JerryS4

Dynamic (or S mode) for these tests.

60614allroad

I got the app and a mount for the iphone. I did six runs, the best results (not all on the same run) were:

0-60 MPH = 4.54
0-100 MPH = 11.91
1/4 mile = 12.85 @ 107.9 MPH
Max HP = 369

Quite similar to Jerry's results. It's a fun app to play with; I'm going back out later to try it with the Allroad....

aquarian

Did you put the transmission in manual so the car could shift at redline for you, instead of the S mode where the car only shifts at below redline?

60614allroad

I did 2 runs in Dynamic and 4 runs in manual (2 of those with mild brake torquing at launch). The best numbers came from 3 of the manual runs; the best 0-60 came from one of the brake torque runs......I know, I know, brake torquing is bad for the car, I won't do it often....call it a poor man's launch control... ;8^)

feralc

All magazines test are performed with brake torquing, and I am sure the manufacturer test too. Also the launch control is basically the same thing I do not think ou can do endless controlled launches without harming the car, it is just too much stress for the transmission.