Pre-Supercharger WI with System 2D

[sebastian]

Hoping to get some general advice before my 2D install. Here?s the situation:

2.8L V6, with aftermarket Supercharger (SC). Suffering from excess heat, detonation, and choking on US California gas (91 octane). Setup leaves no room to tap for WI post SC. As previously discussed on this forum, pre SC WI should be around a 25-30% W/F ratio vice the normally recommended 10-15% ratio. Supposedly this fulfills 2 jobs by first keeping the SC cool and second allowing enough atomized H2O to actually make it into the cylinder. Is this interpreted correctly?

I'd much rather run 6 smaller jets directly into the manifold (custom manifold, part of SC kit, very short runners). Research indicated this setup would be prone to jet clogging and potential unequal water distribution to each cylinder... not good at all.

Using the 2D System and a primer pump as indicated here, ?http://waterinjection.info/phpBB2/viewtopic.php?t=127&highlight=double+flow?, I intend on running 2 jets staggered at different angles along the air intake between the MAF and throttle plate. Both jets will unfortunately have to be located within a foot of the throttle plate, with the SC intake just a few more inches downstream. I have very little room to work with. Here are some initial questions:

2 staggered jets will provide better atomization than one large jet right?

Plan on installing the primer pump in the trunk with a custom tank. Aquamist pump and most everything else will be in the engine bay. Okay?

Micron filter located in the trunk for easy access...post primer pump. Okay?

*W/F ratio? math required for determining an ideal W/F ratio eludes me. Here are my numbers assuming 100% flow rates:

- 6 fuel injectors @ 270cc/min: 1620 cc/min total
- 2X .5mm jets w/ new sys 2D pump (224 cc/min): 448 cc/min total
- 448 / 1620 = 27.65% W/F ratio

Is the baseline ratio that simple? Assuming the 2D is set up correctly, this W/F ratio will be fixed regardless of the actual cc/min flow... right?

Detonation is the biggest problem. But it only occurs at low rpms. If running say 8-10 psi max boost, what?s the earliest recommended point to start WI without bogging things down? I?d like to start at 2.5 psi, but fear this will degrade low end performance even further with such a high W/F ratio.

Lastly, as quoted from ERL concerning the 2D, "Concealed inside this tiny exterior, it holds a very important diagnostic circuitry - it will detect BLOCKED water jet!!!? By what means is this achieved for alerting the driver in the cabin?

Guess I should indicate this install is for a 99.5 Audi A4, 30V, 2.8L, Quattro (PES G2 Supercharged +++), around 310 bhp right now.


TIA.... really appreciate the help.

[Richard L]

It appeared that you have done your home work - wish everyone will do the same.


Two staged jet is good because of the pulsating delivery and also less chance of a total blockage. However, it will not be as easy to detect a block jet unless both jets are blocked. Block/fault detection line will go to ground electrically, can drive up to 1A Load - higher load requires the use of a relay.

Depending on your battery location, if the battery is nein the trunk, Aquamist pump should also be in the trunk. Ideal position og the aquamist pump is nearest to the battery, tank position is not as important due to the presence of the priming pump.

Your w/f ratio will be determined by tuning and power output.

Send some pictures of the install please. I see if I can persuade the forum Boss to run a "Install Gallery".

[sebastian]

Thanks for the reply. Still have a few questions though?

Okay, so I should assume all the information in my first post is correct? If so, cool. However, I?m still looking for ?ballpark? answers to the following:

System 2D detects a blocked water jet. How am I alerted? ?when the red LED on the fiA2 stops blinking???

Battery is in the engine bay. Aquamist pump will probably wind up within a meter of it. What would the max flow of the Aquamist race pump be (in cc/min) with this scenario? The answer to this question is required to determine which jet sizes to test with? and saves me some cash by not having to order additional jets!

Is ChargedPerformance selling that mounting bracket yet? I could definitely use it.

Do you have any numbers out there concerning the lifespan of an everyday primer pump (wind screen) vs. the Aquamist pump? Should the primer pump fail, the Aquamist pump would not be happy, and may become subject to failure as well.

Looking at my detonation issue described in the first post, please take a stab at what psi trigger I should start with during testing.

An ?Install Gallery? on turboICE would be great! I?ll be sure to take some shots of my setup. The tech assisting me with this already has pics posted on Aquamist (the Audi S4 at the top) ......but that setup is waaayyyy different from what?s prescribed here. 8)