Discussion and questions related to the course Launch Control
Hey Andre.I am facing some problems with my motec m800.I cant understand which parameters I have to use from motec.Can you help me??My engine is 600cc Honda CBR 07',naturally aspirated.It has a clutch not as a pedal but like a lever close to the steering wheel,not DBW,not launch switch exists.Its rev limit is at 13400 RPM and idle needs to be tuned from scratch(It's 2500RPM now but without PWM switch or stepper motor on throttle blade for IAC.It's aggressive and not smooth.No PID control is used).Can I use launch on that car or should I install something more??I have 2 wheel speed sensors on left front and rear wheels.
First I go Funcion->Traction control->Setup:
1.Slip calculation mode 1(Ground Speed vs Drive Speed)
2.Slip Units 1(Speed Units)
3.Slip Filter 4(Motec's suggestion)
4.Driven Wheel Balance(Don't understand what controls)
5.TC aim slip comp method 1 & 2 -> 1(Additive not percentage) For Traction Control not Launch I think
6.Launch Retard Throttle Position 0.0(Dont have turbo engine for ignition retard).
7.Launch Activate Throttle Pos 70%
8.TC Aim Slip Filter 2(default) Not for launch.It's for traction I think
9.Launch RPM ctrl Range 100(Is that the margin on M1)
10.Launch RPM limit type 5(Ignition Cut only).Motec recommends 2(Ignition cut with Fuel cut 100RPM above ctrl range)
11.Launch RPM Randomiser 151(Dont know what is about)
12.Control Method 2(Cut only)
13.TC gains are for traction control only??Or for launch as well??
Function-Traction Control-> Addition Setup:
14.TC disable type 2
There are 3 more parameters in that setup but I cant figure out their use.
Now from Function->Traction Control which are the tables that I have to tune for my naturally aspirated engine?I dont need ignition retard(As far as I understood from course).I need a table like the one you tuned on M1(RPM-Vehicle Speed).Which one is that table?Should I go anywhere else to configure sensors or anything else like you did on M1?
Thanks Andre and sorry for those questions but I cant figure out everything
Let's start with the most simple option which is the 2 step style launch control. In the M800 this is called 'Dual rpm' and is a function that you can set up as a digital input. you can simply set this up on a clutch switch or any switch and define your low launch rpm limit. You can add retard but as you say, this isn't helpful on a N/A engine. There is also an option under this function for rpm rise rate which is discussed in the course.
If you want to use a ground speed based launch control system it's a little more complex but not much. You're on the right track as the setup is initially configured in the Traction Control menu however a lot of the setup here isn't strictly necessary for launch control alone.
It looks like you have most of the configuration sorted and you are just wanting to define the launch control table. You can tune your rpm vs ground speed in the 'Launch RPM Limit' table. By default this is probably not configured as a table so you can press 'A' and enable the ground speed axis. You can then define an RPM limit based off ground speed the same way I did with the M1. You could also define another axis based off a switch or pot to adjust the launch target if desired.
Great Andre.This was very helpful.I have already built that map the same way you did on M1.I need to ask one more question.Should I prefer igntion cut only or ignition cut and fuel cut after 100 RPM from ctrl limit(motec suggestion).What is the launch control randomiser (I must choose between 75 and 151)
In general I've used the ignition cut however I suggest trying both and see which feels smoother. There isn't necessarily a right or wrong way of setting this up.
The randomiser defines the way the limit function cuts spark to different cylinders. Again this isn't something you should worry about too much. You're getting down to the last 0.5% where a different randomiser may result in a marginally smoother limit function. This is important for controlled classes with a fixed rpm limit where the driver may end up on the limiter quite regularly.
Great.Thanks again Andre