What’s the sweet spot for launch control?

[Striker's Stinger]

So I just got my jb4 installed with injen intakes and hks spark plugs gapped at .022. Holy shit. This car breathes differently. The intakes makes the car sound like a dragon breathing. Freaking car speeds up after every shift change, 93 octane, MAP2. I’m having a good time.

So my question is, I feel like since adding the intakes the car takes a bit of lag at the beginning but really makes up for it when the turbos hit. I’m wondering if I’m holding down the launch control for too long before letting go and maybe losing power in the launch or if I should just let my foot off the break as soon as I hit the gas and brake at the same time. Anyone have a sweet spot for their launches or what works best for them?!

 

[Snicklefritz]

I seldom use launch control. when I want to take off from a dead stop I use auto hold, push the gas to get rolling then hit the kickdown switch. when I do use launch control I let off the brake the instant the 'ready' sign comes up which is pretty much as soon as you push the gas pedal.

 

[Striker's Stinger]

I seldom use launch control. when I want to take off from a dead stop I use auto hold, push the gas to get rolling then hit the kickdown switch. when I do use launch control I let off the brake the instant the 'ready' sign comes up which is pretty much as soon as you push the gas pedal.

That’s so interesting the auto hold launch. I gotta try that! And I was waiting way after the ‘ready’ sign came on which could be why my launches sick. Are you taking off traction control when you do the autohold launch?

 

[Snicklefritz]

Are you taking off traction control when you do the autohold launch?

nearly always I leave traction and stability on. I have no idea what the difference might be with them off using the auto hold to 'launch.' now we both have something new to try.

 

[AtomicGTL]

2100-2600rpm is the sweet spot.

well for me anyway

 

[JHolding]

nearly always I leave traction and stability on. I have no idea what the difference might be with them off using the auto hold to 'launch.' now we both have something new to try.

Are you AWD or RWD?

I am RWD and use auto hold. I find that with traction control on, the RWD has traction issues from the start, even stock like I am. Once the tires start to lose traction, traction control kicks in and slows the car down.

With traction control off, I get some slight wheel spin on launch, but the nannies do not apply the brakes to get the spin under control and the car is much faster.

 

[Snicklefritz]

Are you AWD or RWD?

I am RWD and use auto hold. I find that with traction control on, the RWD has traction issues from the start, even stock like I am. Once the tires start to lose traction, traction control kicks in and slows the car down.

With traction control off, I get some slight wheel spin on launch, but the nannies do not apply the brakes to get the spin under control and the car is much faster.

I am awd. the rwd stinger is outside my experience. what you describe makes sense.

 

[Audible Silence]

when you say auto hold your talking about the "parking brake" lever you lift up?

 

[JHolding]

when you say auto hold your talking about the "parking brake" lever you lift up?

No. On the GT2 there is a autohold function, that allows the car to stay still without your foot on the brake. You can't build boost or anything, it just acts like your foot is on the brake while you are at a red light. When the light turns green you just mash on the gas pedal. You can actually take off faster as you don't have to release the brake THEN press the gas, you can just have your foot hovering over the gas pedal the whole time.

 

[rpoffen]

I think the only real solution for AWD is a TCU with the launch control torque limit disabled. The stock launch control is too tame, only lets you build up to 2100RPM or so and you can't get enough boost to prevent it from bogging down.
Likewise, if you don't disable traction control, any slippage will cause it to reduce throttle.
I have played with a brake snip type setup, but there are other issues with that.
Now, I have a Lozic TCU, and I have it timed just right (with the full treed at the track) so I build up to about 2600-2700 RPM and 6-7PSI boost at launch (WMI is set to kick in a 6) and it launches like a bat out of hell.

 

[Snicklefritz]

this evening I tried disengaging traction and stability when I got the front row at an intersection, speed limit there is 60 mph, so it's a great place to enjoy a good take off. anyway, two things happened when I got on the gas, I forgot that when you disengage traction and stability that you better not also forget that you are in manual gate, or else it bounces off the red line and disengages the trans until you get your shitz together, which I quickly did by bumping the lever out of manual gate and getting on the gas pedal again. the other thing that I noticed is that the forward collision warning icon was lit up, and it went out when I engaged traction and stability again, never noticed or saw that before.

 

[NS_Stinger]

I cant speak for myself but Ive heard quite a few people having success launching using the e-brake by holding it up and buulding boost before slamming it down and going full throttle.

 

[JHolding]

this evening I tried disengaging traction and stability when I got the front row at an intersection, speed limit there is 60 mph, so it's a great place to enjoy a good take off. anyway, two things happened when I got on the gas, I forgot that when you disengage traction and stability that you better not also forget that you are in manual gate, or else it bounces off the red line and disengages the trans until you get your shitz together, which I quickly did by bumping the lever out of manual gate and getting on the gas pedal again. the other thing that I noticed is that the forward collision warning icon was lit up, and it went out when I engaged traction and stability again, never noticed or saw that before.

I'll try that on mine when I leave work. I do not recall any other idiot lights lighting up when traction and stability are turned off. As to the manual gate thing I'm a '23 GT2, I have the e-shifter, I can't accidentally do that, and I rarely play with the shift paddles so I'm not sure how long it'll hold onto a gear before it takes back control.

 

[vipeboy2000]

I'll try that on mine when I leave work. I do not recall any other idiot lights lighting up when traction and stability are turned off. As to the manual gate thing I'm a '23 GT2, I have the e-shifter, I can't accidentally do that, and I rarely play with the shift paddles so I'm not sure how long it'll hold onto a gear before it takes back control.

if you are in sport mode or in custom mode with sport selected for powertrain, it will only go back to 'D' if you go below 4 mph even with the e-shifter.. of course it will downshift for you if you are slowing down, but it won't upshift for you. you have to pull the + paddle for 1+second to go back to 'D' .

 

[Audible Silence]

No. On the GT2 there is a autohold function, that allows the car to stay still without your foot on the brake. You can't build boost or anything, it just acts like your foot is on the brake while you are at a red light. When the light turns green you just mash on the gas pedal. You can actually take off faster as you don't have to release the brake THEN press the gas, you can just have your foot hovering over the gas pedal the whole time.

View attachment 77460

ah yes, i have that. i'll give it a try vs launch control. tho the dealer i bought the car from put some shit knockoff tires on the car so i dont have much hope till those are replaced.

 

[JHolding]

ah yes, i have that. i'll give it a try vs launch control. tho the dealer i bought the car from put some shit knockoff tires on the car so i dont have much hope till those are replaced.

It's not a replacement for launch control, by any stretch of the imagination. But it does feel much faster than releasing the brake and hitting the loud pedal from stop light to stop light.

With launch control, you are at least building rpms prior to launch.

 

[rpoffen]

this evening I tried disengaging traction and stability when I got the front row at an intersection, speed limit there is 60 mph, so it's a great place to enjoy a good take off. anyway, two things happened when I got on the gas, I forgot that when you disengage traction and stability that you better not also forget that you are in manual gate, or else it bounces off the red line and disengages the trans until you get your shitz together, which I quickly did by bumping the lever out of manual gate and getting on the gas pedal again. the other thing that I noticed is that the forward collision warning icon was lit up, and it went out when I engaged traction and stability again, never noticed or saw that before.

The forward anti-collision system is disabled when both traction and stability control are turned off. This is by design.

 

[rpoffen]

I cant speak for myself but Ive heard quite a few people having success launching using the e-brake by holding it up and buulding boost before slamming it down and going full throttle.

Doesn't work for me, doesn't even come close to being able to hold the vehicle in the staging lights at the track while I build boost.
The only thing that works for me all the time is to have a TCU with the torque limit disabled. I still am in sport mode with stability and traction control off. When the first yellow light comes on, I floor the gas pedal, while firmly holding the brake with my left, when the third light comes on, I release the brake. I am launching at about 2700 RPM with 6-7 PSI boost. Launches like projectile out of a cannon.

 

[Snicklefritz]

The forward anti-collision system is disabled when both traction and stability control are turned off. This is by design.

so are you saying that when the icon is on the system is off? if so then I had it backwards. I will have to look again but pretty sure I deselected forward collision along with all the other nanny systems.

 

[rpoffen]

so are you saying that when the icon is on the system is off? if so then I had it backwards. I will have to look again but pretty sure I deselected forward collision along with all the other nanny systems.

In the owner's manual, in the section on Forward Collision Avoidance (FCA), it states
"The FCA automatically deactivates upon canceling the ESC. When the ESC is canceled, the FCA cannot be activated on the LCD display. In this situation, the FCA warning light will illuminate."