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datkwikracer
12-11-2002, 12:58 AM
Does anyone have it and is it accurate? Would you reccomend it? does it work?
I'm thinking about giving it to a friend for x-mas.

RedSuns
12-11-2002, 01:06 AM
it is not accurate for SHIT.....but it is very CONSISTANT(sp?)....it can tell you the differences in mods that you do...try it out

datkwikracer
12-11-2002, 01:13 AM
u just hook it up to cig lighter right? or does it require other stuff too?

RedSuns
12-11-2002, 01:20 AM
not sure on the actual connections that it requires......but i know that it works off a simple INERTIA switch

SilviaDriver
12-11-2002, 01:57 AM
do not buy it

from wat i read its +-.3sec. plus ud have to mount it so that it lays FLAT! its mainly to measure ur Gforce etc. not really meant to measure 1/4 or anything but it does tho. i read somewhere about it but forgot some info. id link ya..but ud need a login for that forum.

Nerfdude
12-11-2002, 11:33 AM
i had one of the old style Gtech Pros... got it free with a set of BF Goodrich VR4's on my Lebaron &nbsp;<img src="http://www.zilvia.net/f/iB_html/non-cgi/emoticons/tounge.gif" border="0" valign="absmiddle" alt=':p'> actually, i found it to be pretty accurate. all you do is plug it into a cig lighter and mount it on your windshield like a radar detector, and then adjust it so the degree meter thing reads 0 degrees. then you enter your car's weight, select the function, and go run a quarter mile and it gives you the stats. mine's broken, though...

Dousan_PG
12-11-2002, 11:46 AM
i have an Apex Rev/Speed meter
i trust it a bit more of course. its plugs into my ECU and not my cig lighter..
has the same fuctions of the gtech and more.
good toy. i've not testedit yet on the 1/4 mile. i will ifi ever go to a drag strip(i dont care about 1/4 mile) and see how it compares with the official strip #s. hm

Racer X
12-11-2002, 05:56 PM
im not to sure about the new gtech but the old was quite accurate on 1/4 times within .3 usaly but the mph was higher probaly due to fact that drag strips average you last 60 or was it 100 feet either way the gtech does not.if you give it acurate weight it will give you hp that is close still no replacement for a chassis dyno but heh a few pulls will pay for one. btw new gtec has more functions than a rev speed meter or blitz equivlant and cost less (just cause its from j-land doesnt mean its better) just $.02 though

Dousan_PG
12-11-2002, 06:57 PM
RacerX,

please explain to me
how can something that plugs into my cigarette lighter be MORE accurate (if not same) then something that i wire into my computer's brain (ECU)?? because to me, something that's hooked up to my ECU i would see as being FAR more accurate.

please explain that to me!!!

gtech pro competition:
Reaction-Time
0-60ft time
0-330ft time
0-60mph time
1/8mile E.T and speed
1000ft time
1/4 mile E.T. and speed
Horsepower
Torque
RPMs
Braking distance
Handling G's
Accelerating and Braking Gs
RPM vs Time Graph
HP & Torque vs RPM Graph
Speed vs Time Graph
Speed vs Distance
Gs vs Time Graph

From (http://www.gtechpro.com/gtechprocomp_whatcanitdo.html)


Apex'i Rev/Speed Meter
Engine and vehicle speed, traveling distance, battery voltage, graphing, and stopwatch. Peak hold function for all measured values, timing of travel distance(0-100M, 0-200M, 0-400M) Timing of acceleration times (0-100km/h, 0-200km/h, 0-300km/h) Top 5 times are permanently stored. Horsepower calculation Outputs for engine RPM and vehicle speed to activate external relays (i.e.; NOS, shift-light, etc.) Allows speed limiter removal Measurement of acceleration, braking, and cornering loads with the optional G-Sensor

From (http://www.rotormotorsports.com/aprevmet.html)

to me, the Rev/Speed is FAR superior (especially sinc eyou can run shift lights off it and activate NOS..now for a drag car, that's AWESOME)

enjoy the cig lighter. its soo accurate. the only accurate thing its done for me is light people's cigs and that's about it! what is it there for!

check this for MORE good rev/speed info from Import Tuner:
IT (http://www.importtuner.com/tech/0203it_ppapex/)

Nerfdude
12-12-2002, 03:38 PM
um, i'm pretty sure you can get RPM's off of the cig lighter wire... isn't that the wire most people hook thier electronic tachs too for the rpm feed? i may be wrong, but i think i'm right... anyway, what does the rev/speed meter pull out of the ECU besides rpm's anyway? also, i'm noting the g sensor module is an extra option.... the only advantage i'm seeing is that it's permanently mounted and looks nicer. oh, and you can go "yeah dawg, i got apexi shit"...
oh, and it removes the governor limit on some cars. if it removes it on the ka or sr, i can see that as a nice advantage. but then again, if i chose to go with a gtech, all i'd have to do is cut one wire. and then i could buy more wire and a switch and mount it in the dash somewhere so i could turn the governor on and off... and i'd still have an extra 100 in my pocket.

Dousan_PG
12-12-2002, 03:45 PM
it pulls all its info off the ecu, speed (KPH -the one downside of it, i wish it was MPH). also does lap times (good for track use!<img src="http://www.zilvia.net/f/iB_html/non-cgi/emoticons/wink.gif" border="0" valign="absmiddle" alt=';)'>

yes gsensor is extra as well. mines mounted under my center console (i dont have auto seatbelts in my s13)

yes it does remove the speed limiter as well..i havent fixed it on my KA yet, gotta do the tranny wire (off 5th gear?). not like it matters, my final gear keeps my top speed down. i topped out at 160 KPH. i never go that fast anyways, cant get that fast going sidewasy on the track haha..

to me, looks is important. if i dont like my car's looks i wont be happy. i also believe in buying good quality stuff for my car. oh and my friend deals apex, so the deal is sealed haha..i already have an Apex S-AFC and i'll get an AVR and apex gauges, so i like it all the same stuff. most of the engine buildup will all be tomei...its just how i like to do things.

thats just my opinion on it. i am not knocking the gtech or anything, i just feel the RSM is more accurate and reliable and the functions are just as good if not better then then Gtech. my cig lighter lights cigarettes, not tell me what my car is doing.

to each their own.

piratepete420
12-12-2002, 04:06 PM
When you accelerate the front of the car is a little higher than the back. That throws off the gtech and it reports lower numbers. &nbsp;And a the things that plug into the ecu don't account for wheel spin.

Jeff240sx
12-12-2002, 04:10 PM
</span><table border="0" align="center" width="95%" cellpadding="3" cellspacing="1"><tr><td>Quote (piratepete420 @ Dec. 12 2002,6:06)</td></tr><tr><td id="QUOTE">And a the things that plug into the ecu don't account for wheel spin.</td></tr></table><span id='postcolor'>
I am pretty sure it does. &nbsp;But even if it doesn't have a wheelspin correction, I think that it would get the point when the speed reading goes from 15mph to 5 mph, and the rpms fall as well.
-Jeff

Dousan_PG
12-12-2002, 04:13 PM
</span><table border="0" align="center" width="95%" cellpadding="3" cellspacing="1"><tr><td>Quote (Jeff240sx @ Dec. 12 2002,3:10)</td></tr><tr><td id="QUOTE"><!--QuoteBegin--piratepete420+Dec. 12 2002,6<img src="http://www.zilvia.net/f/iB_html/non-cgi/emoticons/wow.gif" border="0" valign="absmiddle" alt=':0'></span><table border="0" align="center" width="95%" cellpadding="3" cellspacing="1"><tr><td>Quote (piratepete420 @ Dec. 12 2002,6<img src="http://www.zilvia.net/f/iB_html/non-cgi/emoticons/wow.gif" border="0" valign="absmiddle" alt=':0'>6)</td></tr><tr><td id="QUOTE">And a the things that plug into the ecu don't account for wheel spin.</td></tr></table><span id='postcolor'>
I am pretty sure it does. But even if it doesn't have a wheelspin correction, I think that it would get the point when the speed reading goes from 15mph to 5 mph, and the rpms fall as well.
-Jeff</td></tr></table><span id='postcolor'>
you know, i'll find out about wheelspin, i wouldnt be surprised if it does account for it, apex is pretty keen on this stuff. i'll get back to ya'll.

Dousan_PG
12-12-2002, 05:34 PM
<!--QuoteBegin--piratepete420+Dec. 12 2002,3<img src="http://www.zilvia.net/f/iB_html/non-cgi/emoticons/wow.gif" border="0" valign="absmiddle" alt=':0'></span><table border="0" align="center" width="95%" cellpadding="3" cellspacing="1"><tr><td>Quote (piratepete420 @ Dec. 12 2002,3<img src="http://www.zilvia.net/f/iB_html/non-cgi/emoticons/wow.gif" border="0" valign="absmiddle" alt=':0'>6)</td></tr><tr><td id="QUOTE">When you accelerate the front of the car is a little higher than the back. That throws off the gtech and it reports lower numbers. And a the things that plug into the ecu don't account for wheel spin.</td></tr></table><span id='postcolor'>
Now please show me how the Gtech is just as good/better/on par w/ the Apex one!! PLEASE TELL ME!!


from the Apex website:

Highly accurate 100m/200m/400m times with trap speed and wheel-spin correction, Horse Power Calculation, and Loss Power Calculation.


Apex Website to Rev/Speed (http://www.apexi-usa.com/meters_revspeedmeter.asp)

the entire info section:

Like the original, the new Rev/Speed Meter GP is a complete multi function measuring device designed to measure and monitor data such as vehicle speed, engine RPM, and elapsed times. However, the strength of the new unit lies in its differences. Probably the most obvious being its completely redesigned look. This new aesthetically pleasing model was crafted to match the likes of other highly popular A'PEX electronics such as the VAFC (VTEC Controller) and the AVCR (Boost Controller). The new screen utilizes the easy to read VFD (Vacuum Fluorescent Display) with built in light sensor used in many of A'PEX's line up. The new unit also delivers a host of new functions. Standard features include: Engine RPM, Vehicle Speed, Travel Distance, and Battery Voltage (All which can be displayed in real time graph mode, numerical mode, or analogue mode; 1-4 channels at a time.), Peak Hold, Replay (With 60 second playback.), Speed Limiter Cut, 0-100m/200m/400m times with trap speed, 0-100km/h/200km/h/300km/h times, Mid Range Acceleration (The user can preset any range of speed to measure.), Stop Watch functions, Best Time Memory, RPM Warning, Speed Warning, RPM and Speed Outputs (For external devices requiring an RPM or speed signal.), Tire Size Correction (For acceleration and timing accuracy.), and Vehicle weight input. One of the most exiting of the new features is the option to utilize the revolutionary A'PEX G-Sensor (Sold separately.). The G Sensor allows the unit to measure G forces in 4-way front/rear/left/right directions. This data can be plotted in a graph display to map acceleration characteristics and lateral G's on the race track, or used in an array of new features including: Highly accurate 100m/200m/400m times with trap speed and wheel-spin correction, Horse Power Calculation, and Loss Power Calculation. By taking advantage of the optional G Sensor, the user can produce extremely accurate power measurements. Usually, when measuring 0-400m times through the speed sensor signal alone, the meter will end measurement too early (shorter distance) due to wheel-spin. Using the G Sensor modifies the speed sensor signal, compensating for wheel-spin and producing impeccably accurate acceleration times.


Apex is superior over the Gtech...thats my opinion!!!

Toso
12-12-2002, 05:57 PM
I'm not sure if you guys drag race or not, but 0.3 seconds is a pretty big difference for ET's. Just thought I'd throw that out there.

LexusRules
12-12-2002, 06:11 PM
i had the Rev/Speed meter GP w/g-sensor on my GS as well and i love it. I took it out to put in my 180 but it broke... i dont know how.. but it did.. depressing!!

the one thing i think it does is gives you too high (good) lateral accel movements due to the cars sway it will read higher than it is. Other than that it was awsome and no complaints.

vsiev
09-05-2004, 03:56 PM
*sigh* ... ok the Gtech works like this.... you plug it in to your cig lighter. That gives it the 1) power (duh) and 2) the ability to read revs.

Inside the Gtech there is a gyro... that acts like a pendulum. This is why it is critical to get the thing set at zero when you start.... because when you begin your run, it measures how hard your car is accellerating with G-forces.
As you accel, the gyro swings to the back sending a signal to the G-Tech that you are hauling balls (or putting if you have a slow car...)

It is true it is about .3 off because honestly it is impossible to calculate these things off of just a cig lighter.... im amazed they did so well to begin with. Ingenuity. Eitherway, it is a good cost effective way to get you into the ball park of where your car stands... :Owned:

Salty_X
09-05-2004, 04:52 PM
Two years later....


http://www.gtechpro.com/gtechprocomp_howitworks.html
http://www.gtechpro.com/gtechprocomp_whatcanitdo.html
http://www.gtechpro.com/gtechprocomp_accuracy.html

thx247
09-05-2004, 05:40 PM
I wonder how it read RPM from the cig voltage...does it just filter electromotive noise from the coil or something?

90RS13
09-07-2004, 10:03 AM
The gtech gets RPMs from listening to electronic noise. All engines make electronic noise that varies at different RPMs. You program it by reving to a certain RPM, and telling the gtech where your at. It then knows what your engine "sounds" like, (electrically) at that RPM. That's how it gets RPMs. The rest is from three accelerometers, on three different axis. (x,y,z) (this is the same technology used for inertial navigation on airplanes) It's not a gyro.(which planes do use) Just 3 accelerometers. A gyro is something that houses accelerometers, so that they won't lose their orientation, when pitch, roll, etc, are introduced. The gtech has no gyro. That's why you have to do things different with it sometimes. For instance, it sucks at measuring lateral or braking G's because all cars have body roll. The accelerometers add any tilt of the unit, to their G's. It is highly accurate at measuring speed though. Horsepower runs have to be run slowly, so that you don't have any jerky pitch movements. Done like this the hp is very accurate too. You have to remember however that the gtech doesn't take into account temp, humidity, and other things like a dynojet would. It also is measuring this while the vehicle is moving, so you are seeing hp after wind resistance, rolling resistance and drag have taken their toll. This is interesting because, you can see how a different bodykit or wing effects your car. If a bodykit make more resistance, creates more drag, your hp numbers will fall. If anyone doesn't know how the gtech gets it's hp, it knows vehicle speed(from accelerometers) it knows vehicle weight(you tell it) from this it know torque, and from that it calculates horsepower. I hope this helps. If there are still questions, ask.

BTW I'm a communication and navigation systems specialist.

90RS13
09-07-2004, 10:05 AM
BTW I'm a communication and navigation systems specialist.

Hope that didn't sound arrogant or anything. I definantly didn't want it to.

Steeles
09-07-2004, 10:43 AM
its ok I just hope the moron that brought this back after two years of death was banned and beaten.

DTS
09-15-2004, 08:58 AM
apexi rev speed meter sucks, i have one and a gtech comp the new one.

the apexi does NOT measure 1/4 mile times it measures 400M, which is 20 feet short of a 1/4 the on;ly thing i like about it is real itme rpm and speed recording.

and you cant download graphs into your computer and analize them which SUCKS

gtech comp you can download all runs and analize them and better your lauching and shift points