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Ground speed based launch control and DBW control

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Hi Everyone I am brand new to this sight and fairly new to tuning in general but I recently bought a few courses and have gotten really into it. I have watched the entire launch control course and the worked examples. Basically I am trying to figure out how to use or create the strategies from the video and the ECU I am using is the Haltech Elite 2500. The software appears to be a lot different then the Motec m1 and Link g4, thus I am having a hard time making any of the strategies in the video work. I did notice I can use a slip percentage based traction control in the Haltech. Is it possible to implement the same strategies using the slip percentage and an axis for ground speed? I also want to set a DBW throttle limit as discussed in the video since the car is a very powerful(over 1000hp). Basically I am having a ton of trouble trying to use any of the strategies mentioned in the video. Anyone who has this ECU and has made this work? Any chance a haltech worked example or even Elite Software Programmer tutorial course is in the works Andre? Greatly appreciate any insight on this topic.

Anyone have insight on this question?

I've just had a chat to the guys at Haltech to make sure I don't steer you wrong here. Right now there is no option for a ground speed based launch control strategy in the Elite. It's only configurable as a basic 2 step style launch control. Full functionality will come in the very near future though.

Thank you andre, very impressed you would do that. Greatly appreciate the help

No problem :)

Hey guys I am also interested in a Ground speed launch control with my Elite 1500. I have noticed that the launch RPM can be configured to have an axis of wheel speed. Does this mean that the Haltech is now capable of Ground speed launch control?

Good question, don't know the answer - 'cept, maybe, if you can impliment an intermediate means of converting a ground speed signal* into a form that the ECU can accept as a wheel speed input?

*if they are compatible, 'might' work, anyway? i would expect there is a compensating option for differing tyre ODs and tyre growth that may compensate for the signal frequency differences?

Be interested to see what they come up with.

Thanks Gord,

I have a wheel speed sensor on one of my front wheels (RWD car). I was just going to set the Launch RPM with reference to front wheel speed to allow 10% wheel spin through 1st gear for example.

If you have that option, try a few different percentages - you'll probably find it is between 5 and 10%, depending on tyre characteristics and track conditions. I would 'expect' the percentage to be about the same in all the gears - but talk to the chaps trying this and see what works for you.

With a solid rear axle, rear wheel drive, it may be a good idea to use the right front for the wheel sender, if you can, as the torque reaction will pull the left front first. Doesn't apply for IRS, though, as both should be pulled equally.

That's great info thanks Gord,

The signal comes from the front left in my case, as this is where the factory speedo cable comes from on the VW beetle. Being a street car, hopefully I keep it on the ground!

Launch control will only be active for 1st gear -- The basic ideal is to set the initial RPM high enough to both slip the clutch and spin the tires initially when you step off the clutch (in other words, don't stall or bog the engine), then reduce the "excess" RPM to stop the clutch slip while keeping up with the traction capabilities of the tire. By the time you get to 15-25 mph, you usually transition into your traction control.

I often see curves that have the RPM dip as the cars goes from 1 to 4 mph, then the RPM limit rises with RPM (reducing the slip slightly as the speed increases -- i.e. the RPM rises slower than the speed).