Water/meth injection

[lpcapital]

I must admit that after reading about xxxJohnBoyxxx and pnosker I got convinced that water-meth is not as bad as I thought.

I personally was never a big fan of it because it is not the proper way to cool the charge. An intercooler is a far better choice particularly because it doesn't cool the charge by filling precious volume with something doesn't burn (aka water). But since adding an intercooler on a DASC is way more work and money that I want to do I decided to get back on my ideas and look at water-meth as the more realistic alternative. Afterall some charge cooling is better than no charge cooling at all.

I did my homework: done reading on various FI and WI forums, read about WI on some kits supplier (Coolingmist, Snow Performance, Aquastealth, Devil Sown). I even talked about it with Teddy at MM today when I called him to buy a couple of things. His take is that evne at 8PSI things get too hot.

What I would like to understand is what type of setup you guys have opted for: pump capacity, noozle size, progressive flow or on-off system, boost controlled or mutliple (boost, MAF, TP). And also why did you opted for a particular setup.

Another thing I'm still struggling with is wheather I will see any performance benefit without a new tuning that would allow me to take advantage of the lower combustion chamber temperature by retarding sparks timing.

It also appears that because of the WI the O2 sensors read a leaner mixture: will this mess up the adaptation levels?

Also John suggested that the boost increase is due to the rotors being more seald as you spray before it. Are we sure it is not actually the water turning into vapor and espanding, thus increasing the pressure in the manifold?

[pnosker]

I would get the basic Coolingmist setup first. It's cheap (on eBay) and you can get Bing.com cashback (google it if you don't know what I'm talking about). I have a 150 psi pump, M-3 nozzle (around 180 cc/min I believe), and I run it off my washer tank. Just the basic system, when boost hits 9 psi. You would want 6-7 if you're still on the stock pulley. It will seal your rotors better and you'll see maybe 9 or 10 psi. I opted for it because it was cheap. I put it in the intake boot so it was a simple install. I think you'll definitely get a performance boost being that it seals the rotors better (more boost) and it will give you a higher octane which will prevent the engine from pulling timing. I would however recommend eventually getting a tune as that's the best way to see more power.

I had a wideband installed when I did my dyno runs today and it never went over 12:1 AFR over 4000 RPM. Below that and it was a little lean, but that's how it was stock too. Stoch is around 14:1, so it's running richer because of the methanol. I am pretty sure it doesn't fully vaporize until it hits the supercharger, and the amount injected isn't enough to raise the pressure by 2 psi, I think. Regardless, it works and it seems to work well. I use PEAK -20 Washer fluid (33% or so meth) + 1 bottle of HEET (around $1.25 each) per gallon of fluid and it seems to be working well. It doesn't use it too fast. I found a leak in a connection which I fixed by tightening which explained my extreme consumption problems I was having. So basically a little over $3 per gallon of meth, which you could probably use for a couple of weeks. I'm also seeing a 3 mpg gain too, not sure if that's related or more closely related to my recent oil change/VCG replacement.