Launch Control Q's

Hey Andre, was just watching the launch control webinar and was just wondering... Since it is very effective at building boost are you ever venturing into untuned zones of the map... for example say a engine does not normally reach 20psi until 6000rpm, but your launch control limiter is set to 5000rpm and it gets to 20psi (an cell you would not have been able to tune in steady state normally) Is this something you need to worry about...

I imagine ignition timing wont be a issue as you are likely firing at TDC or after anyway but do you need to take extra care that it is not running too lean... if you think you are going to be reaching cells you have not properly tuned do you add some fuel first and check it out quickly and adjust.

Not sure if this even happens before, not played with launch control at all before but just a thought.

you've raised some good points.

I think i'ts very rar to have a setup where you want and need more boost than you reach on normal driving conditions. I personally never had such a setup, but I would suggest to intepolate the values regarding to the last tuned cell and go on the save side. Because there is no chance of detonation due the very retarded ignition timing, the mixture can be in a very brought window. Think adjusting the mixture roughly that the cars behavior is as you like and EGT doesn't go to high is sufficient.

It is a good question. I just went back over the drag cars that I've tuned and in pretty well all situations I'm launching at an rpm where the engine would normally be able to make the sort of boost I'm seeing on the 2 step. Even if you are in an area of the map you haven't specifically tuned, this is one of the reasons I recommend maintaining a reasonable shape to the fuel map. If you maintain the shape of the map then chances are if you end up slightly off the tuned area of the table, you will still be close to the correct AFR.

You won't be able to read the AFR on the 2 step as the unburnt fuel and air exiting the exhaust will effect the lambda sensor reading and will show a false lean reading. If you are worried, you can always add a little fuel to the launch control settings but I've never really found this to be necessary.

Thanks Guys :D