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GrandPrix98GT
04-03-2009, 04:29 PM
Went to the track last night. First time out since I've had the car. Managed to get 8 runs in, but I'm pretty disappointed in my times.

Temps were in the high 60s, 92 octane, about 7/8 tank of fuel, stock 18" wheels with the all season tires. Mods are: NEP OTR and a dyno tune. Car made 315whp and 335wtq.

Over the eight runs, my averages were:
60 ft: 2.33
1/4 mile: 14.549
1/4 mph: 98.38

Ran in regular drive and sport, and with stability control on and off. The car felt so slow off the line, felt like it had no power until somewhere above 2k. Not sure what the problem is.
GRRRR8
04-03-2009, 04:36 PM
Get down to a 1/4 tank or less and a 2.0 60fter and you are in the 13.70s easily. 8 runs equal a lot of heat soak too. I bet I could get a 13.50 or better in less the 3 passes. Its not how many passes, its how many good passes with the engine cooled down and a good 60fter that is a fast ET.
-Ray-
04-03-2009, 04:46 PM
Do you have a Dashahwk? Or a HSRK?
I'd be interested in seeing your intake air temps. Who tuned your G8?
GrandPrix98GT
04-03-2009, 05:34 PM
Do you have a Dashahwk? Or a HSRK?
I'd be interested in seeing your intake air temps. Who tuned your G8?

It was tuned by Dyno Tune Motorsports, near Columbus, Ohio. Don't have Dashhawk or a HSRK. I do have a ScanGauge II that I could probably use though.




Get down to a 1/4 tank or less and a 2.0 60fter and you are in the 13.70s easily. 8 runs equal a lot of heat soak too. I bet I could get a 13.50 or better in less the 3 passes. Its not how many passes, its how many good passes with the engine cooled down and a good 60fter that is a fast ET.

I hope the weather will be nice again next Thursday so I can try for some better times.
GeorgeInNePa
04-03-2009, 06:05 PM
Did they do a TCM tune or just an ECM tune?

The trans tune is just as important as the engine tune in these cars.
Atlas
04-03-2009, 06:13 PM
you just need more seat time to get use to the car...
locrzn#92
04-03-2009, 07:19 PM
Something is not right about the tune, only 315 with a Nep and tune. VM just made 340+ with the tune and NEP otr. Even the Cortex and NEP otr made 337hp. WTF?
Atlas
04-03-2009, 08:00 PM
Something is not right about the tune, only 315 with a Nep and tune. VM just made 340+ with the tune and NEP otr. Even the Cortex and NEP otr made 337hp. WTF?
dynos read all over the map... a better comparo would be the stock time vs the modded times, if he has them...
-Ray-
04-04-2009, 03:17 AM
dynos read all over the map... a better comparo would be the stock time vs the modded times, if he has them...

I agree, comparative numbers are the important factor as far as engine tune. Bogging on the line indicates to me that the car was heat soaked though.
Devilish34
04-04-2009, 04:35 AM
Maybe he has short legs and is unable fully depress the accelerator
jbradsh1
04-04-2009, 05:45 AM
Maybe he has short legs and is unable fully depress the accelerator

Well, I'm sure he'd find a way!
locrzn#92
04-04-2009, 11:00 AM
Lol
GrandPrix98GT
04-04-2009, 12:11 PM
They did two dyno runs on my car stock before the OTR and tune were done. Made 288/310 stock, then 315/335 OTR and tune. The car sat only about 20 minutes between runs. The tune included ECM and TCM. Unfortunately, I did not go to the track when the car was stock.


Maybe he has short legs and is unable fully depress the accelerator

LOL. I hope that's not the problem!
jbradsh1
04-04-2009, 12:53 PM
dynos read all over the map... a better comparo would be the stock time vs the modded times, if he has them...

Atlas, you should be a "hall of fame member" with your e.t. and speed. It still blows me away every time I see it. Hek, my cammed car is no better ... for the moment anyway. :devil:

Where is your shop ... even if you don't have one, you can set mine up. Must be a world record for a stock motor G8 GT with just a cai & a tune & X pipe. What's really impressive is that your 60 ft. time is a stinker but the car makes up for it and pulls like crazy to get a 111 mph trap. Just amazing.
johnh
04-04-2009, 05:23 PM
Check the tune, the PCM/TCM will limit torque off the line...and make it really slow out of the hole
jbradsh1
04-04-2009, 07:28 PM
Check the tune, the PCM/TCM will limit torque off the line...and make it really slow out of the hole

Sure. I wasn't criticizing him at all, no one could with that time & speed, it was just a frank observation.
'02 ws6
04-04-2009, 07:53 PM
Much is being looked @ the tune and not @ track surface, prep, conditions, and most importantly DA.

I first ran my GT in June last year, stock, with a DA of 6500+ft, best time was 14.9 @ 97 w/ 2.02 60ft, which IIRC corrected to a 14.0-14.1. Do you know what the DA that night was?

Granted that's still a fairly low time for a CAI/tune car, but the DA might be a big contributing factor as well.
BlackBerry8830/4.2.2 Profile/MIDP-2.0 Configuration/CLDC-1.1 VendorID/104
jbradsh1
04-05-2009, 07:00 AM
Much is being looked @ the tune and not @ track surface, prep, conditions, and most importantly DA.

I first ran my GT in June last year, stock, with a DA of 6500+ft, best time was 14.9 @ 97 w/ 2.02 60ft, which IIRC corrected to a 14.0-14.1. Do you know what the DA that night was?

Granted that's still a fairly low time for a CAI/tune car, but the DA might be a big contributing factor as well.
BlackBerry8830/4.2.2 Profile/MIDP-2.0 Configuration/CLDC-1.1 VendorID/104

Yep, I hear ya loud and clear. But it's an incredible time and speed no matter the DA.