1/4 mile times
 

Does anyone know how accurate those G-tech performance meters are?

Last night a couple friends stopped over at my house at about 10 p.m. One of them brought a G-teck thing and wanted to test my P5. He drives a 94 auto Cavalier and always claims he can beat anyone. So we went off to the local "1/4 mile test facility" which is a two lane road about 5 years of age that was constructed on an abandoned rail road bed. The temperature was about 35* F and humidity was about 52%. Also the altitude was about 550 ft above sea level. This was the first time I had even tested my P5, which is completely stock. I have not put one modification on it at all. We lined our cars up for a race. We had one kid stand there with a tee shirt to tell us when to launch. The G-tech was in my car. If you are unfamiliar with that device, it is a tiny box that uses a suction cup to stick to your winshield and I guess can configure 0-60 and 1/4 mile times all by the G forces experienced during the run. As soon as the kid waved his arm I dropped the clutch at about 3200 rpm. The clock starts on the meter as soon as the front of your car lifts, which is exactly when the clutch begins to pick up. I pulled about a car length and a half away from the cavalier and noticed 7.2 blinking on the meter, which was my 0-60 time. My final quarter mile run was 15.410 at 96.8 mph. I did not believe this for a second. I figured that the road must be running down hill. so we went to the other end (Some guys a few years ago actually measured with their odometers 1/4 mile and marked marked it with two yellow lines at both end) and started there. On that run I got a 15.680 at 92 mph. Could this be right? I never thought a 5 speed P5 coud break 16.5. I did a total of 10 runs and only two runs were over 16 secs. The 15.4 was my fastest run, and most of them were in the upper 15 sec range. Has anyone tested a P5 at an official drap strip? I am still skeptical, but I don't know how that meter can be off.

I have a G-Tech at home and I'll try it this weekend and see what my P5 5-speed records.

Sounds good man

Hopefully next weekend I will get to go to an official strip, and I will take the G tech with me. I can then compare the numbers with official time slips

I've seen several magazines test these and the consensus seems to be that they are 2-4 MPH high and pretty close on the times. Of all the tests I've read, the most that it was off was about 3 tenths. The reason they think that the speed is high, is because when you actually run on a 1/4 mile at a track, the speed trap is usually 30 feet before the end of the run and your actual speed at the 1/4 mark is usually slightly higher than posted on the board. In all the tests they said don't take it as gospel, but it is a useful tuning aid as you can set a baseline and then test mods. Also, the HP function is prettly close as long as you have the ACTUAL WEIGHT OF THE VEHICLE including driver entered. Same goes for any of the other tests. If you don't have the weight right, you'll get bad data. Weigh your car, then yourself, add the two and then enter it when you set it up.

I did this for my Twin Turbo Steath. It me gave a 370 hp and a 13.1 1/4 mile time. I went to the track and ran 12.9 and calculated the horsepower by the 1/4 mile time and trap speed of 108 mph. I came out to be right a 370 hp. So I would say the G-Tech is right on or really close. I took 3 runs and averaged them together. The best was my 0-60 of 4.5 secs. How I miss the hiss of those turbo's and AWD.

If your friends car is a five speed GS-R, then the first run could have been his driving. There are tons of different ways that he could have gotten a much faster run with the intake, not just the intake itself. I can't answer the problem with high power. I have seen official time slips of a GS-R that broke 15 secs with just an intake. If it is not a GS-R, TypeR or is not a 5 speed (autos seem to get fairly consistent runs) then it must have been the G-tech. If you did a bunch of runs and averaged them then I stand corrected. I have watched an Automatic 1.9L Ford Escort run a 18.8 and then a 18.1 after removing the aribox at the same track as the GS-R (the same day too) Removing the airbox all together is a huge increase in airflow to the engine, more than an intake I would imagine.

I drove 10 runs with the G-tech and then averaged the results. My average 0 to 60 was about 7.814. my fastest was 7.2 and my slowest was 8.8. The rest seemed to be just shy of 8 secs. my average 1/4 mile was 15.911 I think ( I already lost the paper that i wrote all my numbers on) and I forget the speed but I heard that is the biggest weekness of the G tech. None of these runs were on a perfectly level road though. I did 5 in one direction and 5 in the other. It was built on a railroad bed but the road has tiny dips and bumps the whole length of it.

just a thought
 

someone could try runing the 1/4 mile track with the g-tech and compare.

Since the G-Tech only has one accelerometer, it is very sensitive to tilt, both the unit and the car. I tried one on my old Accord, and it said I cut a 16.5@83mph, despite the speedometer never getting above 75. My Protege logged a 10.5 sec 0-60, and 19.1@68 mph. At LACR (about 2800 ft), I could cut 17.8@76 all day long (yes, I know my car is slow :().

I'll have to remember to take mine (G-Tech) with me the next time I go drag racing.

did anyone try a 1.8L lx on the track?I wanna know if its worth the trip to the dragstrip tonite..

When I first got my G-Tech I was at the track with it and could'nt get it set up right but the guy would gave it to me used it at the track that day with his '88 RX7 and it was close. You guys that are having probs may not be setting it up right. I'm gonna try mine out tonite in the P5 if it ever stops raining and drys up. I'll keep you guys posted.

hey i just ran my car today and my best time was 16.754 @ 82.68 mph, my r/t was .755 (not that great), my 1/8 mile was 10.794 @ 64.63 mph......just to let you guys know....

well from what i hear, if you set them up correctly, they are pretty accurate. a guy that i know from the street racin crue around here that has a really sweet 1995 TT Supra has had one in his car at the strip a few times, and it was quite accurate, on his best time he ran a 10.9 second quarter mile (running a 150shot of nos, along with all the other crap under his hood) and the gtech said 11.1 seconds..... so its pretty close.

I finally found my G-Tech and I'm gonna try it out tonite if the pavement dries up. I just replaced my stock air box with a APC filter and we'll see how if does. I should've waited to replce my air box and made some passes with it but oh well....i felt like a kid at christmas I just could'nt wait to play with my new toy.

Did you enter your cars weight in? G-techs are "okay," the tough part is knowing how much your car weighs. If you know that ACCURATELY, chances are you are getting weighed at the track and you don't need a g-tech anyway ;)

Check out the Tazzo, www.tazzo.com. Its like the g-tech, but you can calibrate it using track times :)

dave

G-tech time
 

I'm not all that sweet at driving a five speed, but the first time I ran my dad's G-tech on my car I got a 0-60 of 9.06. After that I couldn't get it below 9.6.