×

Sale ends todayGet 30% off any course (excluding packages)

Ends in --- --- ---

Help with Anti Lag

Launch Control

Forum Posts

Courses

Blog

Tech Articles

Discussion and questions related to the course Launch Control

= Resolved threads

Author
2268 Views

I recently had my car retuned and had a flex fuel kit installed and will be picking up the car tomorrow to finally enjoy out here on these Texas backroads. I had attempted to tune the car myself and got pretty far considering how much work the previous tune required, but i hit a few road blocks when it came to flex fuel tuning and setting up launch control. I'll give it to you guys though, your material enabled me to dial in the VE table, ignition maps, and boost control really well. Enough that the tuner who just finished the car only charged me half what he normally would have and was pretty impressed with how far along i got. Thank you. That savings paid for the course and then some.

Now i'm at the point where i need to dial in the launch map on the car. It's an Evo 8 with a 6466 on AEM Infnity and has a 4.11 final drive; the car is on a Hoosier DR2 17" drag radial which i usually air up to about 15 psi. The turbo and final drive combination will make it very hard to 60ft the car without some boost being generated with ignition retard. If it had a 4.3 final drive i could probably get away with a simple rev limit but i will need boost to get off the line without bogging with the 4.11 final drive. What are some tips for initial timing numbers that i should be using with this setup? The previous tuner had some really aggressive anti lag setup on the car; -40 degrees scaling to -28 degrees and building close to 30 lbs of boost. I want to build around 12 lbs of boost or so and keep the valvetrain in decent shape. I understand any amount of ignition retard will generate heat and is not healthy for that car but i'm looking for a good baseline that i can dial in on the street in preparation for the track that will be opening in a month. The tuner that just finished calibrating the ecu did not want to tune any anti lag into the car because he wasn't sure how much damage was done by the previous anti lag map. I could definitely use some pointers for getting this 6466 Evo to cut some nice 60 foots!

I started on some of the tables. I have the car targeting .79 lambda while on the 2 step. RPM is set to hold around 6700. I have the IgnTrimLaunchMap set to initially hit with -20 degrees of timing and ends up around -8 degrees of timing from 5000 to 7000 rpm. All values outside of those ranges are 0. I'm not sure what the Y axis MAP numbers are used for in the IgnTrimLaunchMap table. Are those boost targets or do you achieve more boost by simply retarding more ignition timing? Like i mentioned before i'm only looking to build around 12 lbs of boost, maybe even less boost if that will get the car to launch well enough. I know every car with every turbo will need some trial and error, but i don't want to beat on the car repeatedly if i can get close to a decent starting point now. I attached a screenshot of my current tables. My main goal with the launch map is to hold rpm around 6700 and generate around 12 lbs of boost. This setup reaches full boost (38 lbs) around 5700 rpm. Are any red flags sticking out in my attached screenshot? Are there any other tables that i can incorporate to help with the launch control strategy?

Attached Files

Hi Laurence3, great to hear our courses have been so much help for you.

With the 2 step launch control you need to be very careful as the hydraulic lifters in the 4G63 won't take well to an aggressive amount of ignition retard. In fact anything much in the way of popping and banging in the exhaust can result in the lifters pumping up. For this reason we always ran solid lifters in our drag engines. What you will be able to get away with will depend to a degree on the cam profile and valve springs. I'd suggest you move very carefully and test to see what you can get away with. You'll know if you've gone too far because the engine will idle on 2-3 cylinders for 30-45 seconds after you release the throttle.

The amount of retard you'll need is totally dependent on turbo size and engine capacity, along with your desired launch rpm. I'd start off by retarding the timing by about 10 degrees from the base values (I'm not sure if the retard values in the AEM are absolute or based off the table values). Once you have tested you can start making further changes in 2-5 degree increments until you get your target boost. As a guide I try and keep the numbers at or close to 0 deg total advance unless I'm running a very large turbo in which case I might be as retarded as perhaps -5-10 deg.

Just keep in mind that while you can trim the fuel delivery on the 2 step, you can't take any notice of the measured lambda as it will be inaccurate due to the incomplete combustion occurring.

Thanks for the information Andre. I will advance the timing a bit more accross the board. For some reason I was under the impression that it took a decent amount of negative timing to create boost pressure regardless of turbo size, but I'm all about creating as less stress on the valvetrain as possible. The car has stock lifters, GSC S3 cams, and GSC beehives, not the high pressure ones the standard beehives. I want to upgrade to some Kiggly high pressure beehives next time the head comes off for refresh. I'll definitely take it slow and easy. Last thing I want is to ruin my motor over fireballs and cool noises. The states take a different approach to anti lag tuning from what I've seen. Everyone likes and almost expects the aggressive timing especially with standalone ECUs. I'll take your advice and go about it with much more moderation. Thanks again for the advice

We usually reply within 12hrs (often sooner)

Need Help?

Need help choosing a course?

Experiencing website difficulties?

Or need to contact us for any other reason?