I ran meth on my Evo for years. You can use it to boost you octane and tune for maximum gain. I used it as a way to cool down the charged intake air. It’s safer that way. I’m still ok when the meth ran out. If you tune for octane/maximum tune, when the meth run out you better stay out of boost.
It’s been years, but aquamist made the best kit. And made sure you have couple failsafe built into, like alarm for low tank, check valves so meth won’t fill up your engine and cause hydrolock