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How to Tune with Water-Methanol Injection
We have compiled the results of the numerous kits we have installed and the dyno runs that have dialed them in to present an easy how to guide to get the most out of your Snow Performance water-methanol system!

Featured Article

How to Tune
with Water-Methanol Injection

So you have just bought a Snow Performance water-methanol injection system and you are ready to get your kit dialed in and enjoy the benefits! Like any other part of the engine the system must be properly calibrated and adjusted in order to achieve the full benefit and power it can supply. We have compiled the results of the numerous kits we have installed and the dyno runs that have dialed them in to present an easy how to guide to get the most out of your Snow Performance water-methanol system!

Many enthusiasts simply want more Intake Air Charge Temp. cooling (IAT) and an “Insurance Policy” against detonation on the tune they have now. More power is realized in modern fuel injected vehicles in that the PCM will sense the cooler air charge and automatically “add” power producing timing. Also, with modern vehicles equipped with closed loop knock control, using water-methanol , the vehicles PCM will add timing – to a point – automatically for more power.  

Some want to tune more aggressively and squeeze every last pound of boost and every degree of timing out of their combination. Most are somewhere in the middle. Regardless of where you are, below are some tips on how to tune using water-methanol injection.

GT500 on a SuperFlow Dyno getting ready to tune with Water-Methanol

First off, the theory behind tuning water-methanol is to add injection until you experience quench and then dial it back. Quench is a symptom of over injection which causes a loss of power, white smoke and engine stumbling. When an engine is quenched it means the water and methanol mixture has cooled the combustion event so much it no longer is able to achieve complete combustion. This is not harmful to you engine so long as it is not left running in that state for long periods of time. Quench can be exacerbated by an already rich air fuel ratio or by spark plugs that are gapped too large.

Many of these steps are to ensure that your vehicle is running properly before even starting water-methanol injection. Good tuning practice is to remove variables so that only one aspect is being changed at a time so cause and effect are clear. Trying to tune for water-methanol on a vehicle that does not have a good tune to start with will be like trying to solve 2 problems at once! So with it in mind that our goal is to increase water-methanol injection until we are right on the verge of quench, we can start looking at some steps that will make this process easier and more controlled as you adjust your system.

Step One: As we talked about, a spark plug gap that is too large can easily be quenched . We have found that a spark plug gap of 0.028 works well for most vehicles. Also, ensure your plugs are relatively new with nice sharp edges on the electrodes.

Step Two: Set boost pressure at your desired level. Not all applications will have adjustable boost pressure. On newer vehicles turbo pressure may be electronically controlled. On supercharged applications boost pressure will be determined by pulley size.

Step Three: Pick the right nozzle(s) ! A nozzle that is too large will cause quench regardless of adjustment, and a nozzle that is too small will not give the full benefit of the system and leave power on the table. See the instruction manual for correct nozzle sizing for your power level. The use of too large a nozzle is the number one reason for poor performance.

Step Four: Before activating your Snow Performance Water-methanol system it is time to eliminate those variables we were talking about. With conservative ignition timing, tune for an air fuel ration of 12.0:1 across your operating RPM range. This will establish a solid tune and base line to add water meth on top of. This can be done on a dyno with specialized tools or with several aftermarket devices and tuning software for the do it yourself mechanic. If 12:1 seems on the lean side, remember, you don’t need to cool combustion with fuel now – water-methanol is now providing all the cooling needed.

Step Five: Controller settings -To initially set up your controller injection points set your “start” injection point at approximately half of your maximum boost pressure. Then set the “full” injection point to your peak boost pressure. For most vehicles this will result in a conservative water-methanol injection curve.

Step Six: Turn on your system and make a run ( Dyno or street ). Ideally you will see the air fuel ratio richen by half a point ( 0.5 ) if using a 50/50 water-methanol mix. If power goes down, you are injecting too much. Trim injection by raising the “start” point and/or increasing the “full injection setting. If you find yourself severely adjusting your injections points to avoid quench you may need a smaller nozzle(s) ). If your air fuel ratio does not richen, the system may not be injecting enough, adjust water methanol injection up and ensure your system is spraying. Again, the goal in these adjustments is to start “fat” and trim injection so all quench is eliminated.

Step Seven: It is now time to take advantage of the increased effective octane and cooling and start adding some timing! Advance timing in 2 degree increments until power plateaus and then back it off by 2 degrees. This will give you the most power increase. Most will stop short of this point and add 4 degrees for a 30-50 hp gain – you decide.

Step Eight: Enjoy your new safe power! Your vehicle is now producing more power and is protected.