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g-tac turns iPhone into even cheaper performance meter
One day after spotting the "inexpensive" auto performance measurement tool Dynolicious for the iPhone, we've found another, and it's much cheaper. Liberty For One has released its own automotive measurement tool called g-tac, and its going for just $4.99. For less than half the cost of the Dynolicious tool, you get times and trap speed for the quarter mile, as well as times for 0-60 and 60-0. The g-tac utilizes the iPhone's (and iPod Touch's) accelerometer to determine velocity, so the phone doesn't have to be plugged into the car. The tool also graphs out your last three runs so you can hone your launch technique over time.
g-tac's feature list doesn't appear to have the robustness of the Dynolicious app, which also features metrics for Lateral Gs and horsepower, and there isn't much documentation to detail what g-tac can actually do. The early reviews aren't so hot either, as the first seven purchasers have averaged a rating of just 2.5 stars compared to the four star rating for the Dyonlicious app. Since cheaper doesn't typically mean better, we intend to test both apps against an even more expensive hardware unit, and we'll let you know if either iPhone app is worth your hard earned digital dollars.Gallery: g-tac iPhone app
[Source: Liberty For One]
Reader Comments (Page 1 of 1)
Injected 2:14PM (7/30/2008)
Very much looking forward to the performance meter shootout article.
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KeatMP 3:14PM (7/30/2008)
+1
Xcountryflyer 3:36PM (7/30/2008)
Love the new apps for v2.0 software. +1 for comparison test. As long as they keep updating the apps and getting them more stable and with more features, it'll be a win-win.
KeatMP 2:24PM (7/30/2008)
Me and my brother purchased dynolysious yesterday, and the speed readings were accurate but the horsepower rating was way off. It needs an update.
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Tim 2:59PM (7/30/2008)
Did you calibrate the software before you tried it? You have to go into settings to do that.
My problem is one of the accelerometers appears to be broken in my iPhone, as I can't get the final calibration step to complete.
srDRIVEN 2:25PM (7/30/2008)
what were you driving?
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tankd0g 2:46PM (7/30/2008)
Given what they have to work with it's an impressive toy but not of much use. Better purpose built products are only $150.
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YourNameHere 2:45PM (7/30/2008)
i tested the dynolysious software yesterday and i am really impressed with how well it works. horsepower rated were pretty close. (+ or - 5) 0-60 times were good and the g-load thing is cool to drive around with.
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arturo 3:05PM (7/30/2008)
can someone who bought this things be a little more specific. i am waiting for autoblog to compare this two with a real performance meter, the way i know if this is worth getting an ipod touch even sooner than i thought i would.
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KeatMP 3:16PM (7/30/2008)
Just wait for them to compare the two.
MikeofLA 3:02PM (7/30/2008)
D'oh, i just bought the Dynolysious.
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Allan 3:07PM (7/30/2008)
I wouldn't worry too much yet (i just bought it last night as well). If reviews aren't fantastic, no worries.
KeatMP 3:15PM (7/30/2008)
Yup, calibrated it and everything. The little speedometer was dead accurate, but the HP was off, and I cant figure out why.
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igottamini 10:08PM (7/30/2008)
Since the software has know way of knowing what the RPM of your engine or wheels might be, there are too many unknowns in the equation to find horsepower.
Even if you could calibrate it by tire circumference, like a bicycle computer, there's no way for the software to know what gear you are in...
I don't see this ever accurately giving a HP value.
The G's are what's fun. I'd have bought it just for that feature alone!
Dan 4:38PM (7/31/2008)
@igottamini: you don't need RPM for HP -- just accel, speed/velocity, and vehicle weight. Trust me.
You only need RPM to calculate torque. Again, trust me.
Ian 3:24PM (7/30/2008)
13.86 @ 121? Were you driving a 5000lb AWD automatic truck?
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HPJunkie 3:36PM (7/30/2008)
I'd love to see a 5000AWD truck get a quarter mile in 13.86 -- especially @ 121MPH
maybe it's photoshopped :P
Ian 3:44PM (7/30/2008)
You mean a Trailblazer SS? :p