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A public safety officer let me use his G-tech device today. I never heard of the thing. It is pretty cool. I did a couple of 0 - 60 runs 1st was 6.39sec second one was 6.48sec.
Then i did a 1/4 mile run out in the middle of no where. 1st run was 104.6mph at 14.43 second one was 15.13 at 98.6mph. they were in oppisite directions one had a little tale wind the other head wind so I will avaerage the two and come up with 101.6 at 14.78. This is with 3.25 t-lock rear end. and a C6 shifting manually
Then I did a Hp run it came in at 190hp rear wheels. That don't compute with those kind of numbers.
I would think the HP would be a bit higher. Then I read on a site earlier that with slower gears the hp number is going to be way off. Can anybody take a better stab at what my rear wheel HP numbers should be. I would think with those kind of numbers I would be looking at close to 300hp rear wheel. or am I way off??????? "YES I AM WAY OFF I NEED TO RETHINK MY CARB SET UP AND TIMMING. I NEED A DYNO!." WHat would be your guess if I had 3.70 gears over the 3.25???? anyone, anyone?
I figure you math dudes need some more work!
The G-tech is suppose to be Very very accurate with timing.
 

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CHecking my numbers on another chart on the net the MPH must be off on the G tech. mid 14 should only be low 90's low 13's would get me 104mph. May be my Hp is that low but I can't hardly believe that. Maybe i need to do some tunning with the timming.
 
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TFOB - 300 RWHP, would put that big heavy convertible into the 13s. So if you are running high 14s.... G-techs are fun, but it sounds like you need some "real" track time.
 

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A guy in my club has the G-tech. He said it is not that accurate and I also heard that from a few others. But then I also here from people it is very accurate. Who knows?
I know for sure you have to have it level or it will not work correctly.
 

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They are very accurate, I have one and use it at the track all the time to compare. It's all in the setup, It has to be perfectly level and in the absolute middle of the car and aligned perfectly straight and paralled with the car. The e.t.'s are very close, the speed will read a little high.
 

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I have a G-Tech and the most critical issue with them is the weight value you input for your car. If you underestimate you will get lower hp readings and, conversely, if you overestimate you will get huge hp readings. It simply calculates what horsepower would be necessary to get the amount of weight you input through the quarter mile in the time and at the speed you posted. I used mine at the drags and compared to the actual et's and found it to be consistently a little slower than the traps at the strip. Maybe .3 seconds. The relationship between et and final speed is not something that can be charted as a fixed relationship. If you don't hook up well out of the hole you will have a poorer et with a higher speed. You will also get the same results from a slow reaction time to the christmas tree. I ran a 15.10 @ 92 mph in my vert. That would correspond with your 15.13 @ 98 mph given a little wheel spin.

I wish I could find someplace safe to use the damn thing. Here in the SF Bay Area there aren't many unpopulated long, straight roads left. And, of course, the bloodless CA car nazis frown on that sort of activity so the constabulary really sticks it to you for such behavior.
 

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The G-Tech horsepower ratings are not the same as "rear wheel" horsepower. The G-Tech calculates it based on weight and accelleration. Thus, wind resistance plays a part in it. While your drive line would read the same HP on a chassis dyno if you installed it in any car, the HP of that drive line would drop off significantly in my Expedition because it would be trying to push that shoebox.
 
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