Thought I would pass on some stuff I had read by Sir Harry Ricado (author of The High Speed Internal Combustion Engine) he was the first to experiment with water injection and the alcohol/water injection on supercharged engines back in the 1930's and have been proven to be proven by Bonneville racers Ted Trevor and **** Griffin to be valid today. His test were as follows: Using a test engine set at 2,500 rpm and 7 to 1 compression ratio, the engine was run low grade 86 octane gasoline. Slowly, boost pressure was applied up to the first signs of detonation, which in the case was a Mean Effective Pressure of 168lbs per square inch. At this point the fuel mixture was enriched slightly in increments, and the boost was increased until detonation was again occuring. This process continued until a richer mixture no longer suppressed detonation. After a 60 percent increase in richness, more fuel did not reduce detonation, and in fact tended to increase detonation. At this point Ricardo introduced a fine spray of water into the intake and found that the intercooling effect and stream acted as a anti-ddetonate, making it possible to raise the boost level to a Mean Effective Pressure of 290lbs (which was as high as his dynamometer went). It was also found that the fuel mixture could be leaned out somewhat with the addition of water alone. Later, Ricardo experimented with a mixture of water and alcohol, thinking that alcohol as a fuel would add volatility along with an intake cooling effect, thereby resisting detonation even futher. He found that a 50-50 mixture of alcohol and water was the pratical limit. Any more than 50 percent alcohol did not improve performance and could possibly promote detonation.
With that said I would think if you would think you could use just water only with the correct jetting and not bog at all. And with 50-50 mix you would be able to run more boost with the same jets and possible lean out the fuel so you are not running extra fuel as to control detonation. Some chips have extra fuel to control detonation. So if you are running more alcohol then 50-50 you might see inprovements with the 50-50 and proper tunning. On my turbocharged bike with no intercooler I see 7-8 lbs of boost increase on 91 octane gas.
Might be something to think about.
Chuck
