[mistermike]

Whether to tune for meth spray or not depends on some other factors as well as the philosophical leaning of the owner. Clearly, the car should be properly tuned before the meth or meth/water is applied. Assuming the proportion of the spray is correct, you have the choice of utilizing the extra available octane to allow advancing the spark, or just having the spray as insurance against bad gas, 100 degree heat soaked days at the track, etc. Properly done, there will be a modest performance improvement even without tuning. The thing I most definitely do not recommend is using alcohol spray to prop up a fuel system that is maxxed out. Tuning for meth, makes you vulnerable to the additional points of failure introduced to the system. This is fine, as long as you go in with your eyes open, realizing that even a brief detonation event can be catastrophic with a forced induction motor.