Gtech Pro
http://cgi.ebay.com/ebaymotors/ws/eB...category=46100
It is most useful for keeping track of what I like to call your "real world" HP and TQ. You need to have a deserted 1/2 mile of straight road that is nice and flat for this to work... and an actual scale weight of your car. I mean down to the lb, correcting for your last Big Mac and however much fuel is in the tank. Roll the windows up.
Here's the method: you set the GTech up to start a run, and take off in first MILDLY. You accelerate easily to about 4k (you've got a M6, I presume) and shift easily to second... now you just roll into the throttle for 2-3 seconds till you're at WOT. Run WOT to your redline and shift to third... then coast... then brake to a stop. Save the run, turn around, and do it again in the opposite direction. Repeat. That will give you four runs to average when you get back to your computer. Their software will give you a HP/TQ vs RPM graph that looks like a dyno curve.
I've found these measurements to be extremely precise, and the HP increases that I've seen on the dyno after mods show up almost exactly the same on the GTech. My max GTech HP is typically 88% of the dynojet max HP, due to aerodynamic drag and rolling friction.
If you were to combine a GTech unit with one of the new wideband O2 air/fuel meters that logs data, you'd have a combination that would allow you to assess your actual A/F ratios as the car is WOT under load... a more meaningful measure than when the car is on a dyno. And you'd be able to see the HP/TQ curves that correspond to that A/F data... a useful combination if you're one of the guys that does their own EFIlive or LS1edit tuning.
Or just think of it as a neat toy, and try to set new 60' and quarter mile records every time you drive!
Good luck,
Rich
Think of it as your own dyno... something you can use to confirm that "seat of the pants" measurement we all make.
ET: 13.37
MPH: 111.7 (slightly inflated because it takes speed crossing the quarter mile unlike average of last 200(i think) feet like the track does)
Horsepower: 345 (It says in the manual that Ram Air cars hp numbers will be slightly inflated compared to a dyno becuase of the air rushing in the hood compared to a dyno but still that's ******* sweet)
Oh yah, this was on cold Nitto's, with a shitty launch. I'm CONFIDENT that on a track, with a good launch, with heated tires, and power shift the 1-2 i've got 12.9's. Oh yah, what do you guys think about that horsepower rating?
Edit: I did that horsepower run in first gear, does that matter with the g-tech?
ET: 13.37
MPH: 111.7 (slightly inflated because it takes speed crossing the quarter mile unlike average of last 200(i think) feet like the track does)
Horsepower: 345 (It says in the manual that Ram Air cars hp numbers will be slightly inflated compared to a dyno becuase of the air rushing in the hood compared to a dyno but still that's ******* sweet)
Oh yah, this was on cold Nitto's, with a shitty launch. I'm CONFIDENT that on a track, with a good launch, with heated tires, and power shift the 1-2 i've got 12.9's. Oh yah, what do you guys think about that horsepower rating?
Edit: I did that horsepower run in first gear, does that matter with the g-tech?
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On the old GTech models, though, you don't have the ability to plot your HP/TQ vs RPM curve on your PC... so your results are likely caused by an acceleration spike instead of a computation based on the smooth peak HP seen near 6000 RPM. Try running a smooth acceleration run in 2nd gear as I described above. If you can generate four similar numbers by going twice in both directions on your "track", then I think you've got a much more accurate measurement.
Let me know what you come up with!

