NTMD8R

Note: this is only for people with MRC and PTM and think that you can turn all the "nannies" off using the center console control.

OK, to elaborate on some of those acronyms....

PTM - Performance Traction Management - integrates the Traction Control, StabiliTrak, and Selective Ride Control systems to provide
improved and consistent performance when cornering. The
amount of available engine power is based on the mode selected, track
conditions, driver skill, and the radius of each corner.

MSRC - Magnetic Selective Ride Control -Adjusts the shock dampening
firmness based on driving conditions to improve comfort and performance.

Stabliltrac - Active Handling (AH) - activates when the vehicle senses a difference between the intended path and the direction the vehicle is actually traveling. StabiliTrak selectively applies braking pressure to any one of the vehicle wheel brakes to assist the driver in keeping the vehicle on the intended path.

TC - Traction Control - activates if it senses that the rear wheels are
spinning too much or are beginning to lose traction.
When this happens, TC applies the brakes to the spinning wheel
and reduces engine power (by closing the throttle and managing
engine spark) to limit wheel spin.

The Driver Mode Selector **** is on the console behind the shift lever.
It has a button in the center to allow turning on/off TC and/or AH.

To turn off only TC, press and release the button. The traction off light illuminates in the instrument cluster. To turn TC on again, press and release the button. The traction off light displayed in the instrument cluster will turn off.

To turn off both TC and AH, press and hold the button until
the traction OFF light and Stabilitrak OFF light illuminate and stay on in the instrument cluster.

So this make sense.
This would mean that all the "nannies" are off.

Now, lets add in the MRC and PTM.
Here's where I was confused.

Performance Traction Management integrates the Traction Control,
StabiliTrak, and Selective Ride Control systems to provide
improved and consistent performance when cornering. The
amount of available engine power is based on the mode selected, track
conditions, driver skill, and the radius of each corner.

So press the center button twice to enter PTM.
You now make a single choice of 1 of these 5...
PERF TRAC 1 – WET ACTIVE HANDLING ON
PERF TRAC 2 – DRY ACTIVE HANDLING ON
PERF TRAC 3 – SPORT ACTIVE HANDLING ON
PERF TRAC 4 – SPORT ACTIVE HANDLING OFF
PERF TRAC 5 – RACE ACTIVE HANDLING OFF

I always go right for number 5.
The manual says "StabiliTrak is off and engine power is available for maximum cornering speed."
So I thought this was my optimum setting for autocross.

But I did notice that at times, I was till not getting as much power as I thought the engine had. I also did notice a "bog" sometimes.

I have since found out (and confirmed yesterday) that this is NOT the
optimum/maximum engine performance available.

So, merely do what it tells you to do to turn AH and TC off....
press and hold the button till both "OFF" lights appear.
That's It... nothing else.... zip.
Of course, you should have the MRC **** in "Track" mode to get the
optimum from the Mag Shocks for autocross.

I was pleasantly surprised at how much more power I had (maybe 10%-15%) at the Autocross yesterday... and no "bog".
I could actually spin the rear tires in 2nd gear while on the track.
So, obviously some "judicial" application of the "go" pedal is required.

I guess what it comes down to is:
PTM will always have some computer-controlled "interference".
MRC merely controls the shocks.

You can use any/all/none of the above, depending on your skills.

Theta

Great info!

slesher

Cool. Thanks for sharing

Magister Ludi

Thank You!
I, too, have experienced this unexpected bog or delay when I thought all nannies were off. I'm going to try your suggestion at my next event. Really appreciate you sharing this.

dencos

I found the exact same thing in my first two autocross's. I could not accelerate cleanly out of a corner, there was always a slight bog & hesitation, & you could hear a "burble from the exhaust. The manual doesn't tell you about holding the button down for 6 seconds to turn everything off.

Once you do that the car runs much better.

Now my only complaint is the throttle response both on and off the throttle. After driving my brothers C6Z06 his throttle response is instant, the C7 is not as crisp. When you let off the gas it coast's with no back compression to slow you down for a split second & when you accelerate it is not there instantly.
I really didn't notice until I drove his C6Z06, it fuel's much cleaner and crisper. The funny thing is our times are not that different. He is a much more experienced autocrosser than me, his times are about 3-4 seconds faster, but he is running Hoosiers and I have BFG Rivals. I think with comparable tires our time would be much closer.

I have been thinking about the Diablo Tuner, i've read it is supposed to make the throttle "crisper" , Any comments about the Diablo?

NTMD8R

From what I understand, the Diablo tuner will change the acceleration response,
but (again, to my knowledge), NOTHING (yet) will address the deceleration response.

Here's a thread which discusses this in quite some detail

https://www.corvetteforum.com/forums...-response.html

Skylane765

Thanks, I thought the same. I was using 5 on my Z/28 and it was holding power. So we just hold the button down until both lights light and all is off?

Www.zl1addons.com. John