I decided that the "COMP MODE" 2 step isn't good for track launches. It's more suited for slippery street conditions. For my track session today, I decided not to use "COMP MODE", and I decreased the rear tire pressure to 16psi. My first two passes were at 20psi, but some GTO guys cornered me and told me that they were rockin' with 16psi, so I tried it too.

track conditions:
75*F
calm wind
29.99"Hg
DA ~825'

My first few passes were 13.5's @106ish with 2.2 60' times.

After I got things figured out, I knocked down a few good passes.

60' 2.0000
1/8 8.60
mph 82.23
1/4 13.25
mph 107.2

60' 2.05
1/8 8.63
mph 83.16
1/4 13.24
mph 107.65

60' 1.99
1/8 8.50
mph 83.51
1/4 13.10
mph 107.64

Those were all with a 2800-3200rpm launch with a slow clutch feather, almost no wheelspin.

I think I could have gotten 12's, but the track closed after my 13.10 run.

 

Nice runs - buddy of mine just hit a 12.81 in his RS/SS yesterday.

 

I think I can get a 12.9 if I get a little more practice in.

 

Nice improvement.

 

Very nice!

 

All the numbers add up. Nice runs.

I'm not familiar with COMP MODE? Is that some kind of a traction/launch control?

Street tires?

 

Yes, I was on stock street tires deflated to 16psi.

COMP mode is an offshoot of traction control. It is engaged by pressing the traction control button twice quickly in sucession. When activated, the car's MFD says "competition mode" activated, and it is designed to optimize wheelspin for the best possible launch. If you hold the gas pedal on the floor with the vehicle stopped, a two step rev limiter activates, and holds the RPM at 4200. Once the clutch is released, the normal rev limiter datum is selected.

At the track, it doesn't optimize wheelspin, it just causes the car to badly bog down to 1700rpm on launch, and gives me a very consistent 2.25 short time, and a 13.55@106.5.

On the street, it might work great, but at the track, the surface is too sticky for the computer to understand what to do.

 

Ok so that's the launch control feature that people have been talking about. Sounds like it doesn't work well. Must be similar to what the C6's have had for a couple of years. I don't think theirs works great at the track either.

Sub 2.0 60ft's are very good for street tires.

I wouldn't have thought that lowering the air pressure that low would work with modern tires and their stiff sidewalls. I know racing my past Camaros with Eagle F1's/GSC's that lowering the pressure below 23-25psi would cause the middle of the tread to buckle up on launch as the sidewall wouldn't deform under the low pressure. This would result in a bigger loss of traction.