maximum flow for 0.4 mm, 0.5 mm, and 0.6 mm Aquamist nozzles

[mushin]

This is for my supercharged Focus (big boost Jackson Racing Eaton/roots style supercharger running 14 psi of boost). I'm not sure which nozzle will be best to start with, and I want to know what the maximum flow rate is for those three sizes. The 1s kit comes with the 0.5 mm nozzle, if I'm not mistaken, but I wonder if this will be too much for a Focus that is (before injection) making about 180 whp. Should I start with the 0.4 mm nozzle?

[Richard L]

I think the 0.5mm jet is a good start. I based the WI rate by your power output of 180whp. Not sure what that would translate it flywheel HP - I guess it will be around 220-230HP?

You will require approximately 500-600cc/min of fuel per 100BHP. if you are injecting 1.1 litre of fuel /min then one 0.5mm jet will equate to about 20% of water to fuel ratio.

We normally recommend between 10-15% but due to your lack of intercooler and making boost on top of the standard compression ratio(?). I think 20% is about right.

Please post your results when possible.

[JohnA]

Richard,

Another relevant question I think:
Is there any rule-of-thumb regarding the activating boost-pressure for the WI?

[mushin]

Thank you, Richard. On the Focus, 180 whp works out to probably around 210 flywheel hp. Does this change your assessment any? Thank you for the information!

[Richard L]

No, 0.5mm jet is fine, roots type supercharge tends to have higher discharge temperature than the centrifugal type, the 0.5mm jet shoudl work well.

[Richard L]

John,

Rule of thumb for the onset of water injection for normal unmodified factory car should be just nelow the factory boost pressure.

10% of water will normally allow 1 compression ratio increase or arounf 3.7psi. Other factory such as ambient temperatures and fuel grade woudl affect the quoted figure.

[Richard L]

Mushin,

Does the Jackson Focus kit come standard with 14psi?

[JohnA]

Originally Posted by Richard L

John,

Rule of thumb for the onset of water injection for normal unmodified factory car should be just nelow the factory boost pressure.

10% of water will normally allow 1 compression ratio increase or arounf 3.7psi. Other factory such as ambient temperatures and fuel grade woudl affect the quoted figure.

That's roughly what I thought.
Cheers Richard, I'll add this info on my website if you don't mind 8)

[mushin]

Originally Posted by Richard L

Mushin,

Does the Jackson Focus kit vcoem standard with 14psi?

Richard,

No, it comes stock with 5 psi, at best. I have a larger crank pulley and smaller supercharger pulley, 42 lb. fuel injectors, and custom tuning.

[Richard L]

Mushin,

Unless you have your compression ratio decreased, you need to run at least a 0.7 or 0.8mm jet - no intercooler assumed.