http://www.gtechpro.com/index.html

Anyone ever used one of these Performance Meters (or know someone who has)? They're claiming it's accurate to +/- 1% on hp and torque and +/- 2mph on the 60 ft, 1/8, 1/4 times. Anyone actually seen one in action and/or know if these claims of accuracy are realistic?

 

my friend had the first gen version. was not very accurate when we tried it out on my brother's gsr.

 

Hmm... maybe the newer ones are more accurate.
From what I've read, this thing plugs into the cigarette lighter (and that's the only connection to the car). I find it hard to believe that it is getting accurate engine readings through just the + and - readings of the cig lighter port.
Anyone else seen these before?

 

I have a newer one and have used it quite a bit and if you take the time to calibrate and set it up correctly it can be very accurate. But some vehicles you will have a hard time setting it up because it will get a "dirty signal" from the power source. It doesn't take readings from the engine thru the cig lighter, it uses the voltage reading from the cig lighter (or other 12v source if it's hardwired) to read the rpm's of the engine. It uses that reading along with the reading from the gyros, and gives your results based on the distance v. time formula. It's kind of weird how it works, but it's a good tool to have if you tweak you car a lot and want to see how different changes affect your cars performance.

One thing I HATE about it is the suction cup does not stay put and will fall out of your windshield causing it to "thunk" on the dashboard which can't be good for those sensitive gyros on the inside. It comes with a permenant mount kit but I can't bring myself to drill/screw into my interior. Well..hope that was helpful.

 

That IS very helpful.
I'm looking into this type of system to help with tuning my AEM EMS, so pretty fair accuracy is a must. I'm getting tired of shelling out appx $300 every time I add new components and have to have the thing dynoed. I know it will never be able to take the place of a dyno run, but one of these combined with the datalogger should keep me from having to dyno quite so often.
Thanks for the input.

 

They are pretty accurate, again if they are calibrated correctly...

It's just based on Physics and math, that's it... A gyro measures lateral acceleration, and based upon your car's weight (which must be input) it will calculate the speed, distance, and time when you are driving...

It just uses Calculus to constantly integrate with respect to time, the position function to get velocity function, and then it will integrate the velocity function to get the acceleration function... Just how an airplane is able to track it's speed, distance and acceleration... It's all mathematics...

it's only as accurate as the user/operator, just as a telescope is only as accurate as the observer...