[Richard L]

What is your goal with your experiment? I believe improving the BSFC (Brake specific fuel consumption) has to be the aim.

I have not heard any reports on engine damage running 50% of water to fuel, it just looses power. More probably due to lack of capacity of the ignition system.

M50/W50 puts less stress on ignition system. For most, it is easier than upgrading up the ignition system. Alcohol engines normally requires multispark ignition system.

I love to see your tests/result involving on monitoring AFR, MBT, EGT and power output. If those figures, you can see estimate BSFC and compare the merits of water and methanol.

Fortunately you have find those experiments on dozens of research papers published.