Water or Water/Methanol Injection DIY

[06YarisRS]

Originally Posted by CrankyOldMan

McMaster is good like that--basically overnights stuff to me if I order early enough in the day.

Good catch on the check valve. The highest cracking pressure I could find on McMaster was 4 psi and they were all crazy expensive. Any chance you can disassemble the valve you got and put in a stronger spring? You'd have to find the right one by trial and error, not sure if you can get a selection of springs locally or if you'd have to try and order a bunch from McMaster.

I frickin' love MaMaster-Carr! Amazingly friendly service, great prices, huge product selection, knowledgeable staff (from my first experience). And, yeah, that shipping time...awesome! From my limited experience, it seems they set the bar.

Actually, I think the check valve is going to serve it's purpose in this way. The water solenoid will protect against unwanted injection when the engine is running, the check valve will keep fluid from heading toward the motor when the engine off. I think the crack pressure of this valve is only about 1 psi. I also wonder how much vacuum is on the intake side of TB butterfly at idle. Maybe enough to siphon, but, again, I'm hoping that the solenoid gate valve looks after that. The above said, I plan to test the system extensively before it gets operated on the car. This is SO much fun!!! Haha. BTW, I'm pretty sure that typical water/methanol check valves are in the 16 to 20 psi crack range. My pump only does 80, haha, so it should be interesting to see what kind of pattern and volume I get out of it.

Question for you, Sam...

Since I'm not looking to gain any power here - simply provide a higher effective octane number - in your opinion, is any amount of water injection helpful? For example, if I couldn't meet the full recommendations of load/boost etc water volume, would lesser amounts still help to some degree? I'm not sure that it's a truly linear relationship, or if there is some kind of minimum needed to have any effect.