Accuracy of G-Tech Performance timers

[Guest]

yeah dont doubt it its just that as I said I dont know much about gtechs

[Benny]

I have a G-Tech Pro Competition and the power, torque readings can be quite accurate when the right vehicle weight is entered. I weighed my car on a weigh bridge before doing runs and I was quite suprised at the results. I can also down load the data to my PC and print all the graghs of time, torque, power etc. It's a great device and fun to use.

[turb06]

I take it this is the newer version that superseeded the one I have, how much was it?

Dazza.

[ktford]

14.5 quite acceptable for a stockie at "the bank"

Scotty

[ZAP]

Have a look at www.gtechpro.com, the GTech Pro Comp has been discontinued and replaced with the RR and SS versions. US$299.95 for the RR version is great value...now all I need is for them to make it in blue backlighting

[Trough Lolly]

  Benny said:

I have a G-Tech Pro Competition and the power, torque readings can be quite accurate when the right vehicle weight is entered. I weighed my car on a weigh bridge before doing runs and I was quite suprised at the results.

im still scepticle..

fair enuf u weighed your car.. say it was 1500kg. fair enough.

BUT my poitn still stands if u change the diff ratio to a shorter gearing the acceleration is still going to be stonger and faster than the stock diff.. therefor making the power figures to be greater than they should be..

its to easy to fool if it just runs of g-forces..

[ZAP]

I understand what you are saying, but the HP is not just calculated by G's.

The unit will measure gearchanges, RPM, curb weight, G's and even the squat of the car when you launch. It is a very impressive piece of equipment for the AU$400 it costs. While I would not think it is perfect, I would think with the accurate figures, it would be -/+10% on its readings.

It is not a replacement for the drags, but a handy tuning tool just as a dyno is

[Guest]

  Trough Lolly said:

[bUT my poitn still stands if u change the diff ratio to a shorter gearing the acceleration is still going to be stonger and faster than the stock diff.. therefor making the power figures to be greater than they should be..

its to easy to fool if it just runs of g-forces..

in this case the shockers if stuffed will allow more movement body roll showing more g's for a split second. I think the makers would have used a g sensor that compensates for this.

still scepticle like you though

[poida97]

In my opinion G-techs are far more consistent than dynos in their power readings. Dynos (as we are all aware) have great variances between each other and need to be recalibrated to maintain accuracy. There are also too many variables that need to be monitored in order to compare different dyno's readings.

G-techs work by measuring acceleration and time and they use those to calculate torque and power at the wheels. It is all mathematics. You can calculate the average net power developed at the wheels of any car with a quarter-mile timeslip printout. Is it an accurate figure? It is exact. The problem is that it includes power-sapping losses due to wind resistance, lack of traction, driveline friction, temperature, humidity, and driver ability. For that reason it is not the exact power that the car PRODUCES (the GROSS power output).

Your car's engine may be capable of producing 500 horses and it may be capable of running a 12 second quarter- but if you do the run at half throttle and it takes you 20 seconds- will a G-tech still show 500 hp? Of course not. The same applies to a dyno. Dynos have that one extra variable- that is that they need to be correctly calibrated.

[Turbo6man]

  Trough Lolly said:

  Benny said:

I have a G-Tech Pro Competition and the power, torque readings can be quite accurate when the right vehicle weight is entered. I weighed my car on a weigh bridge before doing runs and I was quite suprised at the results.

im still scepticle..

fair enuf u weighed your car.. say it was 1500kg. fair enough.

BUT my poitn still stands if u change the diff ratio to a shorter gearing the acceleration is still going to be stonger and faster than the stock diff.. therefor making the power figures to be greater than they should be..

its to easy to fool if it just runs of g-forces..

Diff ratios, wheel sizes, gear ratios have zero input to the G-Tech's calculations. It uses the force of accelleration measured over time - simple, no more no less. If you enter correct weight it can also calculate power. As has been said, it is a true or "real time" measurement of the force/power applied to the wheels and the power readings will be lower than what a dyno will show because it takes into account ALL outside variables acting upon the vehicle at the time of the "run".

If you're skeptical (or can't spell), go learn some physics or get a technical buletin from G-Tech to understand how it's done. And, as for accuracy it is more in the order of 1% not 10%. BUT - like any instrument it is only as good as the operator and errors can easily creep in if not used exactly according to the "book".