I just had my '09 CTS-V Automatic (completely stock with 3,000 miles) on a Dynojet dyno. The temperature in the shop was reading between 100 and 101 degrees F and very humid. The car's temperature gauge said 99 degrees F.
The shop owner thinks there is another 30 HP in it if the weather was better. I will run it again in the mid-winter to find out.
10-08-09, 01:39 AM
Considering the weather conditions, your numbers are damn good in my opinion!
Wait until the coldest day of the winter and run the car on the dyno, but see if the shop can strap the car down and let it cool down for about 20-30 minutes or as long as they will let it sit in order for your car's heat soak condition to cool off. If your car is heat soaked, the dyno numbers won't be accurate. You want the car to be run when it's in it's optimal temp "sweet spot" range when running it on any dyno.
10-08-09, 06:27 AM
I got 454 rwhp stock on dynapack at 100F and 10000000% humidity :P
Didn't check what I got after mods, but waiting on headers and to change my pulley from 9" to 9.5" then we shall see how high you can go in such crappy weather.
Aero1 i think you would only do that if you were looking to get a topscore or something. In my opinion you would want to have your car heatsoaked and fresh off the road so you can tune it to real scenarios and bad conditions. y'know, things that might happen when you actually drive the car.
Very good results, especially considering an auto and the weather!
10-08-09, 09:33 PM
Low_Et did you dyno your car in "competition mode" or did you just hit the "trac" off once ?
I just turned off the Traction control (pushed the button once). I thought the "Competitive Mode" just turned off Yaw Control.
By the way, the run was in fourth gear.
Nice... I always assume 18% drivetrain loss and 456 RWHP equates to exactly 556 crank hp.