This is how many EMSs do it. Fixed timing, and fixed additional fuel percentage. DSMlink puts it in the Antilag settings, AEM calls it Fixed Spark Alt, etc.

For turbos the size of the EVO16g that are already quite efficient at producing boost with low exhaust gas energy, I've never found the need to go negative in timing to get more boost than I can effectively use. Every setup is different though. On large turbos it will often take negative timing and 5-10% extra fuel or more to wake the turbo up. By running aggressive antilag settings on the EVO turbo (when I had DSMlink wired in) I've nearly pegged the 30 psi boost gauge, but don't expect any small shaft turbo to last very long, and naturally, you'd be hard pressed to launch effectively with this much boost as has been mentioned earlier in this thread. Another thing to consider is that the more aggressive your fixed timing/fuel modifiers are, the harder it will fall off when it transitions to the normal timing and fuel maps. It's not uncommon for the boost level to **** the bed as soon as you get the car moving, which is of no help of course.

For most small turbo setups, fixed timing of zero degrees and no fuel added is plenty of motivation as long as your launch rpm is normal (5500-6500 rpm). At lower RPMs you need to get more aggressive. A while back on DSMlink when the stock clutch was losing at life I found that a low rpm stutter (4k rpm or so) with aggressive antilag settings would build enough boost to still run 1.6s but without enough RPM differential to overheat the clutch on the launch and bollix the rest of the run.

My appologies for the long ramble. Tephra, I'd love to see a fixed timing mod for the launch limiter.

 

Good point well said