G-Tech run in 928SP SuperCharger - 0-60 <4.4sec!
06-20-2006, 10:13 PM
#61
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Stopped by Andrew's house tonight and got a quick ride.
HOLY ****
That car is FAST!!!! It's the first time a car has actually thrown my head back far enough to hit the seat. I couldn't stop smiling and I was just the passenger!
HOLY ****
That car is FAST!!!! It's the first time a car has actually thrown my head back far enough to hit the seat. I couldn't stop smiling and I was just the passenger!
06-20-2006, 10:13 PM
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Originally Posted by Larry928GTS
The weight input into the G-Tech will only affect the horsepower and torque readings it gives. The weight has nothing to do with any of the time, distance, or speed readings. The RPM calibration will also only affect the horsepower and torque readings, and not the time, distance, or speed stuff. There is no provision to input aerodynamic drag, so if the weight is input correctly, and the RPMs are calibrated correctly, the horsepower and torque readings will be lower than those from a DynoJet.
Ummm..I am not quite sure the above is true either...
I know what the book says..I also scoured their technical information about this...but....with no adequate information...
The G-TECH....has 3 inputs...
1...The built in accelerometers
2...The signal from lighter...which I assume is reading the revs from the alternator AC..spikes...
3...User input....
If the quote was true....HOW does it know how far you have gone ??
If it was attached to a double decker bus....it would HAVE TO KNOW ITS WEIGHT ...surely ?
It has no gps...so cannot know that way....
Im still puzzled lol....
All the best Brett
06-20-2006, 10:21 PM
#63
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Originally Posted by Big Dave
Stopped by Andrew's house tonight and got a quick ride.
HOLY ****
That car is FAST!!!! It's the first time a car has actually thrown my head back far enough to hit the seat. I couldn't stop smiling and I was just the passenger!
HOLY ****
That car is FAST!!!! It's the first time a car has actually thrown my head back far enough to hit the seat. I couldn't stop smiling and I was just the passenger!
Then for ****s a giggles I lit 'em up and left about 200' of rubber.
Later after dinner I tried to do another run, but there was a cop just down the road, so I thought it best not to go for it. Thursday night is drag night down at the strip, so I'm now planning on going down there to have some safe legal fun!
06-20-2006, 10:35 PM
#64
Originally Posted by BRETT AINLEY
Ummm..I am not quite sure the above is true either...
Originally Posted by BRETT AINLEY
The G-TECH....has 3 inputs...
1...The built in accelerometers
2...The signal from lighter...which I assume is reading the revs from the alternator AC..spikes...
3...User input....
If the quote was true....HOW does it know how far you have gone ??
If it was attached to a double decker bus....it would HAVE TO KNOW ITS WEIGHT ...surely ?
It has no gps...so cannot know that way....
1...The built in accelerometers
2...The signal from lighter...which I assume is reading the revs from the alternator AC..spikes...
3...User input....
If the quote was true....HOW does it know how far you have gone ??
If it was attached to a double decker bus....it would HAVE TO KNOW ITS WEIGHT ...surely ?
It has no gps...so cannot know that way....
06-21-2006, 07:12 AM
#65
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Originally Posted by Larry928GTS
Do a couple of runs, change the weight input, do another couple of runs, and you'll see.
The accelerometers tell it the forwards acceleration. It then knows the acceration and the time of that acceration. That's all you need to know to determine how fast you're going, and how far you've gone. The cigarette lighter connection is reading RPM from the alternator. Power the G-Tech from a portable power supply or 12 volt battery on the passenger floorboard and it will measure speed and distance times just as well as if it were plugged into the cigarette lighter. Doesn't matter if it's a bicycle, double decker bus, or an a freight train as far as the not knowing the weight when it's measuring speed, distance, or time.
The accelerometers tell it the forwards acceleration. It then knows the acceration and the time of that acceration. That's all you need to know to determine how fast you're going, and how far you've gone. The cigarette lighter connection is reading RPM from the alternator. Power the G-Tech from a portable power supply or 12 volt battery on the passenger floorboard and it will measure speed and distance times just as well as if it were plugged into the cigarette lighter. Doesn't matter if it's a bicycle, double decker bus, or an a freight train as far as the not knowing the weight when it's measuring speed, distance, or time.
I know I am being dim here but....
IF you tell the accelerometers that you have started moving...
Then you move for say 10 seconds.......
HOW do they know how far you have moved ,with no gps and no weight input ??????
They know you moved...they know the speed of acceleration...they can even tell you stopped accelerating.....
But as they did not know where you started....how can they possibly know where you finished to measure the distance....
Apologies to all for not being very bright...lol...but I was bright enough to buy a 928...so that should excuse me a little
All the best Brett
06-21-2006, 07:56 AM
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Newton's 2nd law: F=m*a
The above equation also indicates that a unit of force is equal to a unit of mass times a unit of acceleration. By substituting standard metric units for force, mass, and acceleration into the above equation, the following unit equivalency can be written.
1 Newton = 1kg * m/(s^2)
One Newton is defined as the amount of force required to give a 1-kg mass an acceleration of 1 m/s/s.
Since the accelerometer measures force, and the computer measures time, and I assume it knows the mass of some known bit inside the G-tech, it should be able to calculate distance traveled. Pretty cool stuff.
The above equation also indicates that a unit of force is equal to a unit of mass times a unit of acceleration. By substituting standard metric units for force, mass, and acceleration into the above equation, the following unit equivalency can be written.
1 Newton = 1kg * m/(s^2)
One Newton is defined as the amount of force required to give a 1-kg mass an acceleration of 1 m/s/s.
Since the accelerometer measures force, and the computer measures time, and I assume it knows the mass of some known bit inside the G-tech, it should be able to calculate distance traveled. Pretty cool stuff.
06-21-2006, 08:11 AM
#67
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Originally Posted by BRETT AINLEY
I know I am being dim here but....
IF you tell the accelerometers that you have started moving...
Then you move for say 10 seconds.......
HOW do they know how far you have moved ,with no gps and no weight input ??????
They know you moved...they know the speed of acceleration...they can even tell you stopped accelerating.....
But as they did not know where you started....how can they possibly know where you finished to measure the distance....
Apologies to all for not being very bright...lol...but I was bright enough to buy a 928...so that should excuse me a little
IF you tell the accelerometers that you have started moving...
Then you move for say 10 seconds.......
HOW do they know how far you have moved ,with no gps and no weight input ??????
They know you moved...they know the speed of acceleration...they can even tell you stopped accelerating.....
But as they did not know where you started....how can they possibly know where you finished to measure the distance....
Apologies to all for not being very bright...lol...but I was bright enough to buy a 928...so that should excuse me a little
http://www.proamauto.com/gtech.htm
From the above link:
"How Does The G-TECH Work?
G-Tech/Pro Competition has three high-precision accelerometers that measure changes in speed. G-Tech/Pro Competition measures 1/4 mile time, by integrating acceleration. This is the same process used in Missile Guidance Systems and is known as inertial navigation. So if you start from Zero and you know how much your speed is changing, then you know what your speed is after a given time period. When you start from zero and you track time and speed that gives you distance as well. To measure Horsepower you will need to input the weight of the vehicle and the G-Tech will do the rest. A unique feature is G-Tech's ability to sense RPM's. RPM's are sensed through the cigarette lighter through a proprietary process so no installation is required."
In summary, weight is NOT a factor for the GTech to do 0-60, 1/4 mile, etc.
06-21-2006, 12:56 PM
#68
Brett:
If you tell me that you traveled at an average speed of 60mph for a period of one hour, I would know that you traveled a total distance of 60 miles. I wouldn't need to know where you started, where you finished, or how much the weight was, and it wouldn't matter. All that would matter is that I knew you went a distance of 60 miles and did it in one hour. If you also tell me the weight, I can calculate the horsepower then, since I'd know how much weight was moved how far and how quickly it was done. If you then tell me the RPM, I can calculate the torque based on that calculated horsepower and the RPM. That's basically what the G-Tech is doing. If you gave me an incorrect weight, the horsepower value that got calculated would be incorrect, but you would have still traveled the same 60 miles in one hour. If the weight and therefore horsepower value was correct, but the RPM was incorrect, the torque would be the only thing that would be inaccurate.
If you tell me that you traveled at an average speed of 60mph for a period of one hour, I would know that you traveled a total distance of 60 miles. I wouldn't need to know where you started, where you finished, or how much the weight was, and it wouldn't matter. All that would matter is that I knew you went a distance of 60 miles and did it in one hour. If you also tell me the weight, I can calculate the horsepower then, since I'd know how much weight was moved how far and how quickly it was done. If you then tell me the RPM, I can calculate the torque based on that calculated horsepower and the RPM. That's basically what the G-Tech is doing. If you gave me an incorrect weight, the horsepower value that got calculated would be incorrect, but you would have still traveled the same 60 miles in one hour. If the weight and therefore horsepower value was correct, but the RPM was incorrect, the torque would be the only thing that would be inaccurate.
06-21-2006, 01:58 PM
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Originally Posted by Larry928GTS
Brett:
If you tell me that you traveled at an average speed of 60mph for a period of one hour, I would know that you traveled a total distance of 60 miles. I wouldn't need to know where you started, where you finished, or how much the weight was, and it wouldn't matter. All that would matter is that I knew you went a distance of 60 miles and did it in one hour. If you also tell me the weight, I can calculate the horsepower then, since I'd know how much weight was moved how far and how quickly it was done. If you then tell me the RPM, I can calculate the torque based on that calculated horsepower and the RPM. That's basically what the G-Tech is doing. If you gave me an incorrect weight, the horsepower value that got calculated would be incorrect, but you would have still traveled the same 60 miles in one hour. If the weight and therefore horsepower value was correct, but the RPM was incorrect, the torque would be the only thing that would be inaccurate.
If you tell me that you traveled at an average speed of 60mph for a period of one hour, I would know that you traveled a total distance of 60 miles. I wouldn't need to know where you started, where you finished, or how much the weight was, and it wouldn't matter. All that would matter is that I knew you went a distance of 60 miles and did it in one hour. If you also tell me the weight, I can calculate the horsepower then, since I'd know how much weight was moved how far and how quickly it was done. If you then tell me the RPM, I can calculate the torque based on that calculated horsepower and the RPM. That's basically what the G-Tech is doing. If you gave me an incorrect weight, the horsepower value that got calculated would be incorrect, but you would have still traveled the same 60 miles in one hour. If the weight and therefore horsepower value was correct, but the RPM was incorrect, the torque would be the only thing that would be inaccurate.
Now why didnt g-techs explanatory stuff ..make it that easy lol
Many thanks
All the best Brett
06-21-2006, 04:49 PM
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Originally Posted by Larry928GTS
Do a couple of runs, change the weight input, do another couple of runs, and you'll see.
The accelerometers tell it the forwards acceleration. It then knows the acceration and the time of that acceration. That's all you need to know to determine how fast you're going, and how far you've gone. The cigarette lighter connection is reading RPM from the alternator. Power the G-Tech from a portable power supply or 12 volt battery on the passenger floorboard and it will measure speed and distance times just as well as if it were plugged into the cigarette lighter. Doesn't matter if it's a bicycle, double decker bus, or an a freight train as far as the not knowing the weight when it's measuring speed, distance, or time.
The accelerometers tell it the forwards acceleration. It then knows the acceration and the time of that acceration. That's all you need to know to determine how fast you're going, and how far you've gone. The cigarette lighter connection is reading RPM from the alternator. Power the G-Tech from a portable power supply or 12 volt battery on the passenger floorboard and it will measure speed and distance times just as well as if it were plugged into the cigarette lighter. Doesn't matter if it's a bicycle, double decker bus, or an a freight train as far as the not knowing the weight when it's measuring speed, distance, or time.
As much as..uh..i tried
i couldnt get the accleration to be abrupt enough to start the runs. Also, the movement of the airplane with the brakes on and the power up disrupted the acclerometers. Yeah, as said, the sensor knows exactly when the run is started which is when the the car moves. weight is not need for 0-60 or 1/4 mile.
when you go to the strip Andrew set the GTECH up and run it simultaniously with your runs. Get up to the line and staged...stop...hit the button and wait for the green light on the tree. It helps to get staged first as once the other guy gets stage they may run the lights pretty quick and you wont have time.
06-21-2006, 10:38 PM
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Tony- I was aboard one of AA's 757's [Rolls-Royce engines....] one night that was nearly empty- we were going to Dallas and I wound up in the cockpit. Chatting with the Captain, I asked him to do a max-thrust takeoff. Listen- you know the 757 better than I do, but dude, it was dead calm and I counted the seconds: That plane got to 80 knots in 9 seconds flat! 0-90 mph in 9.0 seconds-your Gtech won't record that?
How did you power it, by the way? Not 28 VDC I think...
N!
How did you power it, by the way? Not 28 VDC I think...
N!
06-22-2006, 12:13 AM
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Originally Posted by Normy
Tony- I was aboard one of AA's 757's [Rolls-Royce engines....] one night that was nearly empty- we were going to Dallas and I wound up in the cockpit. Chatting with the Captain, I asked him to do a max-thrust takeoff. Listen- you know the 757 better than I do, but dude, it was dead calm and I counted the seconds: That plane got to 80 knots in 9 seconds flat! 0-90 mph in 9.0 seconds-your Gtech won't record that?
How did you power it, by the way? Not 28 VDC I think...
N!
How did you power it, by the way? Not 28 VDC I think...
N!
I think the problem is that, although it is quick, it doesnt have the immediate launch like a car would. Its that launch that triggers the whole thing. If it is too slow the GTECH figures it as some sort of movement and aborts the run.
With the brakes set the "bucking" of the airplane at higher power messes it up..
Kinda stuck in the middle of two ways to do it.
yeah, empty they get up and move!
I ferried a 767ER empty from MCO to ATL one day...acceration doesnt even begin to describe it...9secs would have been slow!!
was a ****** to land though!
06-22-2006, 03:02 AM
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Wow. Low 12's has got to be possible. If you read this months Car and Driver they have quarters on a few cars including the GT500 Mustang, Vette and an M6. Can't remember th times on the first two( It think the Mustang was around 13.1) but the M6 had a trap speed of 120mph and a low 12 time if memory serves.. Lots more meat and electronics on that car to get it to hook up. So, solve the hook up and launch and you'll get the time.
06-22-2006, 12:58 PM
#74
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I love the "Rennlist" effect...
One person mentions product X and w/in the next week that companys stock goes up by a factor of 10.
Tony should be getting kickbacks from GTech.
BTW Tony, my Mr. Dyno has full programmable barometric correction factor, and IIRC drag capabilities. I should send it to you for trial as I've never used it.
One person mentions product X and w/in the next week that companys stock goes up by a factor of 10.
Tony should be getting kickbacks from GTech.
BTW Tony, my Mr. Dyno has full programmable barometric correction factor, and IIRC drag capabilities. I should send it to you for trial as I've never used it.
06-22-2006, 01:14 PM
#75
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So speaking of which...autometer makes a somewhat similar product in a guage format...thought it might fit rather nicely with my AFR guage into a Faussett doorpillar guage pod....Autometer DPIC, anyone know how they compare in terms of accuracy?