Can't wait to see an N/A Z engine build. However, you won't need water injection to make 12:1 work. Many european production cars are running 12:1 on the street tuned for 91 octane. Why not run something more in the 14:1 range. At that point you could really see the benefit of water injection on a high compression engine. It's all really in the tuneing. Personally I think with proper injector sizeing you could run a car with 14:1 static compression and make nearly the same peak power with out without the water injection. Just my $.02.
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