diegodog

is 140hpw on the gtech only testing first gear to redline in the ball park? I have a vehicle weight of 3200.

I am going out tonight to do midnight runs through the gears but just want to make sure this 140 hpw number is in the ballpark for 1st gear before I do a bunch of runs. The run was done on relatively flat ground.

stage 1.1 w/ Borla cat back on the k flash.

Xyntax

Just 140?! Man, I didn't know it was that bad.

diegodog

It's freaking raining here but if it lets up I am going to do some runs tonight. I was hoping to see 200 hpw with the borla and the claimed 20 hpw from 1.1 but I am highly doubting it, esp with the 140hpw 1st gear run.

Dont know much about cars so I am hoping the hpw will pick up in 2nd and 3rd but no idea if that holds true or not. I am also gonna shut the cz off once I get consistent runs with it on. Then we will see if the 500 bucks paid off.

LAter

Speed Racer

I have had better results using 2nd or 3rd gear. Just slowly pull away from and get it smoothly into the gear you want to use (2 or 3). Then floor the throttle and do not let off until you reach redline.

It also helps if the stretch of road needs to be smooth, level, and straight.

Genom

ALso remember the G-tech must have exact car weight. Guessing will get you a guessed HP number. Have your car weighed with you in it and a full tank of gas so you can properly put in the right weight.

Finally, A G-tech unit will always register a little lower than a dyno since it is in a moving car that is pushing through air, so depending on teh car's drag you'll lose a certain amount of HP, especially in 3rd.

r0tor

iTrader: (1)

yup, in 1st gear the run will be too short and the g-tech won't have enough resolution to get a decent reading.

Speed Racer

In the colder months I also ran into problems with wheel spin in 2nd gear (J flash, Stage 1). That is why I mentioned using 3rd gear too.

adrian-1

Third gear redline is in the 90+mph. That could mean a night in jail. I would recommend 2nd gear, redline is around ~70mph.

Omicron

A few of suggestions on how to improve the accuracy of your GTech:

- Find some scales and weigh your car so you're not guessing. Truck weight stations along interstates or racetracks have them.
- Find a dyno shop and dyno your car so you can accurately set base HP numbers. But first, make sure your read up on HOW to dyno this car, as it's not easy. Hint: You have to disconnect the rear ABS sensors to get anywhere close, or the car will go into "limp" mode and drastically cut horsepower at a time of it's choosing.
- Pick your best-guess HP number for the base calibration and stick with it. The GTech will give you good "change" numbers this way.
- Make at least 3-4 (5-6 would be better) runs for any given test. Average them, or pick the low or high ones... but stick with the same ones each time.
-Make your runs in 4th gear if possible, as it's a 1:1 ratio.

1stRX8

4th gear? On the street? Scary.

I have done all of my dyno pulls in 3rd b/c it doesn't stress the thing too bad. I want to know how much power it makes, not how long it will last.

From a testing POV, 4th is good though. If you are looking only for changes, 3rd should be just fine.

Omicron

Agreed.

Tim Benton

I had my FD weighed and plugged that in to the older model g-tech. It gave consistent range of rwhp in the 289ish, +/- 5. Then when I went to the dyno (dynojet248c) It came up with 296. Close enough for me to do like Omicon stated, use the same technique using the g-tech and the same run comparisons and it's usable data.

Tim

rev-2-9k

played today with a gtech and only got about 155.