powerloss from WI/tuning for WI

[jesuscookies]

Okay, Call me Jack Handey if you must, but I think I am having a deep thought

I am about to begin running water injection in my single turbod, 400RWHP, rotary powered, 93 RX 7. My 2s system is all hooked up, just need to tap the injection nozzle, and fine tune. I also have some pure Methanol on order. The car, for saftey reasons of course, is tuned pig rich at about 10 to 1 under full boost/high RPM conditions.

My question is this. If I run the WI with just distilled water, and do not touch the current tune on the car, am I going to lose horsepower? If so, how much power can I expect to lose?

Second, If I run a mix of 50% Methanol, will this in anyway counteract the powerloss of just running straight water. E.G. will this act as high density fuel, and cover some of the loss from the water?

I am asking these questions for several reasons. First, I have heard numerous horror stories about turbo'd rotaries and poor tuning. Secondly, I don't understand enough about the WI system at this time, to add saftey redundies into it, ensuring that nothing would be harmed if the WI failed. Finally, I can't tune for shit and do not trust anyone within 1400 miles to tune my car.

Any advice, and or input would be greatly appreciated.

[Charged Performance]

At almost any level of fueling just adding water injection of any amount worth mentioning and making no adjustments will generally reduce power output - at overly rich settings not only will it reduce power but between the amount of fuel and amount of water being added you need to be concerned about fouling plugs and bore wash (assume this is still an issue in rotaries). I know that rotaries can both be det prone and very easily damaged by det relative to recipricating but don't overdo it with quenching your cylinders. At a rich condition methanol will not be any better than water. Keep in mind that at 10:1 there was no oxygen left about 2 AFR factors ago - it doesn't matter how much of a combustible fluid you put in, it isn't going to burn any better than water.

If you are going to tune this yourself, you really should take baby steps tuning without the WI using a WBO2, knock sensor and EGT. Find out where you should be without water injection. Then start injecting a little bit of water and see where that gets you. Small steps over time will get you there and you will learn a lot along the way. I know for those of us that can't just sit on a dyno all day long fiddling this self-tuning method takes a while and we get impatient to move - but just like turning on the track slow in, fast out. Take your time and get a good feel up front and going forward things will move along alot faster including your car.

Oh and after you just got a good feel for various fuel/water/methanol mixtures then you get to play with timing over it all.