I got my GTECH off ebay today ($50 brand new on ebay) and I will be doing some tests tomorrow. It rained all day today so I couldn't really play with it. Just playing with the g's was awesome. I still don't get how this thing knows when im going 60 mph or when ive gone 1/4 mile, but its been tested and proven. I'll let you guys know what my vert can do tomorrow! I just need to get an exact weight for the HP reading. With only a cat back and intake i don't think I'll like the numbers, but I'm sure it will motivate me for some more mods! After I give her a good tune up this weekend I should put up some better numbers.

 

i want one. i haven't ever really played with one in person, but it seems like a great tool for a tuner to have.

don't take the numbers as gospel, though. In a few cases, the g-tech has proven to match dyno numbers, but really...it's just a tool to let you know what your mods have done for you.

do a bunch of baseline runs and average them. Then, compare those to runs after each of your mods. It's a good way to tell how much power you've gained.

 

They're cool. I got mine for ~40 when they were blowing them out; it was a great buy. If yours does not read exactly 1.00 g when the display is vertically facing upward, or -1.00 g when downward, you can take the case off and turn a small potentiometer screw on the PC board to adjust the gain and get it back to +- 1.00 g when vertical. Here is a pic if the guts:



The potentiometer screw is the tiny silver circle in a black square, between the two blue capacitors.

 

^ Hey, thanks!

 

Now that's more new info for the day. Nice. New Turn signals, and fixing an inaccurate G-tech, you guys rock.

 

You will find it brutally accurate.

My stock TII showed 170 net HP.

Do get an accurate weight before doing a horsepower test.

 

are you serious? They are the most criticized piece of equipment I've ever seen.

They're horribly inaccurate. If you ever try to say you hp numbers are such-and-such, as stated by G-tech, people who know their **** will laugh at you. Same thing with 1/4 mile times. If G-tech tells you 15.00, but you've never been to the track, again, people will laugh at you.

 

Maybe people who are afraid of technology will laugh at you.

There's no good reason why an accelerometer measured 1/4 mile time can't be *reasonably* accurate. (Horsepower numbers are subject to a lot more factors.)

I surely wouldn't use one the judge any sort of competition, but it's not like the 1/4 mile time is going to be totally useless. It's a lot better than the famous "butt dyno".

 

To get good readings, you do have to be very precise in mounting & setting a G-tech.

My time slips & G-tech readings matched within .1 sec & 2MPH. (15.1 @ 91)

As for HP testing, the door sticker weight is useless.
You have to get on a scale.
My TII with me, my stuff, & a half tank of gas = 3320.

 

yes, it's definitely better than the butt-dyno. And you can track changes from one state to another of your vehicle (ie., the difference between stock and with a cat-back exhaust).

But for overall numbers, it's not all that great. Maybe it's how people calibrate them or something, but it's not something to solely rely on if you want solid numbers.

 

If you're finding it that badly innacurate, you're using it for the wrong purposes.

I find it useful for telling me how much power I'm getting out of new modifications, even different brands of gas, vs what I had before.

You have to do like five runs each, then average out the top three runs. You need that consistancy.

 

i mighth ave to start this in a new topic, but obviously my car isn't running right. My 0-60 times and hp were TERRIBLE. I noticed a lot about my car recently (ive only had it for a month) and im definately going to put some hours into it this week.

1. It backfires when i shift above 6500
2. I get NO power around 6000 and higher
3. I get a popping and pinging out of my drivers side tail pipe at idle

I was getting an 02 sensor code before and that pressure sensor code too i believe. Ill check those out, swap the plugs (should i get 2 leading and 2 trailing plugs?), maybe a fuel filter, and I'll see how much better i do.

IT said somewhere around 80 hp. I estimated thwe weight and everything so its not that accurate. In an S5 Vert i should be getting quite a bit more, even at the wheels. I may try some fuel system cleaners too.

 

The only hard part is that when doing the quarter mile with the Gtech your reaction time is perfect, because when you start moving the gtech starts. The track experience is alot different from finding some open road and running the Gtech. The Gtech is a fun toy though.

 

When I first got my car. (Before I noticed the fuel pulse dampaner was leaking) I did a Gtech run. Not knowing the weight of the car, and before I was doing many searches on this board.

The car had an alignment/balance problem on the tires, it would start to shake above 50, and the shifter bushings were gone, as well as a somewhat clogged/melted cat. I haven't run the car with it since I fixed all this stuff, so the graph is not very acurage. I still suck at launching also.

Just figured id share a picture of what information gets loaded on the computer when you download it from the gtech.



It also is probbably lower/inacurate then it should be becuase ive got a couple exaust leaks and 115k on the motor. Once I get the car in better shape I will do the run again. I bought the car from a young fellow who wanted to add big wings, paint it yellow and put ugly rims on it. So im fixing his mistakes and trying to restore it to its stock beauty.

There is also a friends GTUs run, but he insisted his car weighed 2600 lbs, but I think he was full of it, anyways I put his run on there too....

It looks like my car really beings to drop off above 5k. Im not exactly sure why yet, but its on the list of things to be checking out. (I have a 1988 TII)