I've been reading up on WI and the findings listed show that there is little or no beneficial gain from running more than 50% methenol to water when injecting it in the engine as an anti-detonation remedy. I know Spy is running straight Meth and I now have a good source for straight meth for my personal use, but if there is no gain for using more than a 50/50 mix I might as well make it last longer.

Does anyone have any information that supports or contradicts this information. My information is from a good but dated source: HPBooks' 'Turbochargers'

Thanks for any input on this.

What spy said provided the your injector for the meth is large enough.

Agreed. Thermodynamics tells us that the latent heat of evaporation of water is higher than most fluids. That is why it is so good at cooling. It takes a lot of heat to force the liquid water to change state into a gas. The meth is raising your effective octane. That is why you pull fuel out while the meth is being injected.

Yes the graph listed, did show that the level of fuel required did drop as Meth was added. This still had no additional effect to prevent detonation beyond the 50/50 mix from what they were sying though. They stated that meth, being a fuel has it's limit for predetonation as well.

I'll see if I can scan that graph in tonight and post it up for reference.

Here is a scan of the chart from HPBooks 'Turbochargers' book showing what we are discussing. The chart doesn't differentiate between straight methynol and a 50/50 mix like I remember, but it does show how water injectionsupresses predetonation further than simply richening the mixture ... to a point.

I'll look for the paragraph that mentioned the lack of benefit from straight meth.