ZeroBanger

I know this is not the right forum, yet Im not sure which one to put it in, so here is my question. I have a Water Injection setup inwhich I have installed a 6.32 GPH nozzel. I need to find out my percentage of water to fuel at any given duty cycle. I want it to stay between 15-25 pct at all times, definately not go over 25 pct. I found that to convert CC/MIN to GPH I should take CC/MIN X .016 to get GPH. With that in mind I came up with the following, is this correct?

On a side note, RC Engineering's home page said that thier injectors Max out at 80 pct...when my engine blew I was at 80 pct Injector Duty. Doest his sound right? I would have thought the injector duty should be able to reach 100 PCT without running out of fuel.

Nozzel: 6.32 GPH

3500 CC 56 GPH
Duty Cycle CC GPH Ratio Duty Cycle CC GPH Ratio
0.49 1715 27.44 23.03% 0.66 2310 36.96 17.10%
0.52 1820 29.12 21.70% 0.67 2345 37.52 16.84%
0.54 1890 30.24 20.90% 0.68 2380 38.08 16.60%
0.55 1925 30.8 20.52% 0.69 2415 38.64 16.36%
0.56 1960 31.36 20.15% 0.7 2450 39.2 16.12%
0.57 1995 31.92 19.80% 0.71 2485 39.76 15.90%
0.58 2030 32.48 19.46% 0.72 2520 40.32 15.67%
0.59 2065 33.04 19.13% 0.73 2555 40.88 15.46%
0.6 2100 33.6 18.81% 0.74 2590 41.44 15.25%
0.61 2135 34.16 18.50% 0.75 2625 42 15.05%
0.62 2170 34.72 18.20% 0.76 2660 42.56 14.85%
0.63 2205 35.28 17.91% 0.77 2695 43.12 14.66%
0.64 2240 35.84 17.63% 0.78 2730 43.68 14.47%
0.65 2275 36.4 17.36% 0.79 2765 44.24 14.29%

Marshall

Looks right, but you have to know what pressure you're system is at. That nozzle is 6.32gph ar 40 psi. Also, injectors should be ok up to 100%, you just lose tunability past 85 %.

ZeroBanger

thanks, does the pump default at 40 PSI?

Marshall

Should be 60 psi.

ZeroBanger

This pump didn't come with any instructions on how to change the Speed. I know it can be 40 or 60 PSI. So if the nozzel is 6.32 @ 40 PSI, that means its 9.48 @ 60, thats crazy.

maxcooper

Fuel injectors are rated at 43.5 psi. Unless you are running that pressure (stock is 38 psi-ish), the rated injector sizes aren't exactly right. But they are in the ballpark.

If the flow rate increases on the water injection like it does with fuel injectors, it will flow 6.32 * SQRT(60/40) = 7.74 Gal/hr at 60 psi.

-Max

ZeroBanger

cool, thanks Max, I'm gonna run about 40 pct denatured alcohol with the water, that should keep my car from getting too much water. The rest will burn I guess.