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About water meth injection systems

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Water meth injection 

I have been asked if I could do a bit of a write up on this subject to help others understand how wmi works.

Water meth injection can be used for a cooling aid or for extra octane.
Let’s keep it basic with a 50/50 mix, the most effective and proven mixture. When you get a well balanced mixture you will run richer and cooler. 
Pure virgin grade methanol is the only option, if you use any other methanol you will have no joy and can be very dangerous for your engine if tuned on wmi. Always make sure your supplier is a reliable source, or ask your tuner for assistance. 
A good concentrated methanol will enhance your octane to 105 107ron, giving a cleaner burn. A cleaner burn means a more efficient burn( easier to ignite) this will allow you to run more timing giving a bigger bang in the combustion chamber resulting in more power.


With aiding water you will need distilled water or something similar. Using tap water can cause problems ie blocked jets and corrosion due to mineral deposits. The water in the combustion chamber cools the burn this in turn will prevent detonation/knock. The science behind it is on the compression stroke the water evaporates in the air. During the stroke the Water gives higher pressure giving more down force on the stroke and lowering Egts at the same time. 
On the market you have several types of kits, the most effective reliable and advanced kit I have found to date is Aquamist. They have been going for over 20 years and constantly developing. The kit kit consist of a control board, pump, relays, fast acting valve, flow sensor that picks up on air in the lines, wiring harness to splice into the car ecu system this also covers boost fail safe, map sensor, injection and a 5v map switching signal and a nice gauge. 
This kit has many setup features a few are 
• Adjust what rpm/boost you want the wmi to come in 
• Setup for a single one off spray at a certain rpm/boost level
• Set for the kit to come in progressive 
• Set a window to trigger fail safe
• Can be setup to run on a third party ecu
• Low level meth warning on gauge 
This kit is one of the only kits I know that runs a true progressive kit. 
5v map switching 
This is a very complex setup, if your tuner can implement this you can add even more fail safe features IE  if you run out of wmi on WOT the meth will turn off and switch to your safe map. The beauty of this setup you can run a none wmi tune and only use your wmi tune for the odd serious fun. This can all be done via a press of a button while driving at any speed from the aquamist gauge. 
So now we have the basics of what wmi is and what a good kit can achieve, all you need now is a perfect install and a good reliable tune these are 99% the reason why engines blow up. Lack of knowledge is also dangerous!! 
The final results
Injecting wmi  gives cooling, a cleaner burn, more octane, allowing more boost and timing resulting in more power. Which is great but the best and ultimate thing about wmi, the power is consistent! It will push the same power pull after pull. You will never suffer with heat soak again.
So this is my understanding of wmi, if any body would like to add to this then please feel free to do so. 
Every day is a school day. 



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Good write up from someone who actually knows what he’s taking about.

We are lucky to have you on here Ben.

No longer associated with ASN  :D 



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