Just a correction: the water & methanol are mixed together in the same tank and injected together into the intake tract, so not possible to run out of one or the other, only both at once. If that happens then it's exactly the problem Dougal descrbies, screamin' EGT's!
Water meth does do a very effective job in lowering EGT's but is a continual expense as opposed to a one time expense aftercooler. Overall it's often cheaper to do a turbo upgrade so you can tweak up injection pump or even add larger injectors to get your power.
Nothing wrong with W/M and I hope to build a kit for mine, but just suggesting there's other options too, sometimes cheaper at that. I want W/M for occasional power adder, not for fulltime use.
