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Discussion Starter #1
The HFS-3 is exactly what I want but I would like a few things clarified. Looking at the system the kit seems very easy to install. I like the plug in wires (reduced installation errors) and I like the quality of the components.


  • Failsafe (boost) - Did some research and want to make sure I have this correct. I take the wire of the ECBS the goes to the ECU and inline splice it to normally closed relay contacts on the HFS-3. If for whatever reason the failsafe activates the relay opens, shutting power to the ECBS which then closes which results in the turbo wategate opening. This reduces/limits boost to mechanical boost level.

Is this correct?

What is the Mechanical boost level on OEM Turbo?

If I upgrade to a Dominator 3.0xtr, you can order with wastegate from 9-19psi (15psi being std). Would you want to order the turbo with a 9psi wastegate in case the failsafe activates you only able to boost to 9psi and not 15psi? Is there any performance lost between the 9psi & 15psi wastegate (ie spool, pwr)?


  • Input wire – Just need to connect these two wire to any of the 4 fuel injector wires, correct?

Thanks for your help!
Larry

 

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Sorry for the late reply.

1. You have done your home work well, the HFS-3 system fail safe circuit will fo exactly as you described. It is also possible to use the "safemode" output channel to your ECU. It will not be as secure as the relay output (your original option). This is because an electronic circuit cannot work in the event of a electrical power loss.

However, you can use the relay output to actve the car's "safe-mode" instead of reducing boost. Don't forget "test-mode activation" will reduce boost anyway.

2. I cannot anwser your question about the OEM's mechanical wastegate setting.

3. You will experience a difference in 9psi/15psi spring because the OE BCV may not have the dynamic range to contol the full boost swing. With a weaker spring, there a tendency to loose boost at high boost and RPM as the back pressure at the inlet of the turbine housing builds up.

I am not familiar with the Dominatot set up, is it an external or internal wastegate?

4. yes two wires to the injector (-) anyone of the four and ignition switch at the ECU. I have provided some help on the wiring for the Subaru ecu at: Aquamist HFS-3 forum - waterinjection.info

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Richard
 

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Discussion Starter #3
Sorry for the late reply.

1. You have done your home work well, the HFS-3 system fail safe circuit will fo exactly as you described. It is also possible to use the "safemode" output channel to your ECU. It will not be as secure as the relay output (your original option). This is because an electronic circuit cannot work in the event of a electrical power loss.

However, you can use the relay output to actve the car's "safe-mode" instead of reducing boost. Don't forget "test-mode activation" will reduce boost anyway.

2. I cannot anwser your question about the OEM's mechanical wastegate setting.

3. You will experience a difference in 9psi/15psi spring because the OE BCV may not have the dynamic range to contol the full boost swing. With a weaker spring, there a tendency to loose boost at high boost and RPM as the back pressure at the inlet of the turbine housing builds up.

I am not familiar with the Dominatot set up, is it an external or internal wastegate?

4. yes two wires to the injector (-) anyone of the four and ignition switch at the ECU. I have provided some help on the wiring for the Subaru ecu at: Aquamist HFS-3 forum - waterinjection.info

You may need to register.

Richard


Thank you for your reply.

The Blouch Dom 3.0xtr has an internal wastegate setup. It's a bolt on factory location turbo. When you order it, it comes with a 15psi wastegate (hope my terminology is correct) unless specified different. (9-19psi option).

My plan is to also upgrade to a Grimmspeed ECBS (3-port) which will eliminate the orfice, so i wont have to worry about sizing it. Should have better spool and perfomance with it.

I really cant wait to get this kit installed and tuned. Have to save up some $$$ though. Child support sucks, LOL!!;)



One last thing. I know that this kit is designed to mount in trunk. I would really like to fab up some kind of mounting bracket/housing to mount the pump to the front bumper to ultilize the stock washer fluid tank. I have 2 kids and need to use my trunk alot so this would be a good option for me. I would like to weld up somthing nice to protect it from the elements but still allow for good ventilation.

Is there any reason not to do this? I
'm planning to mount the control unit in the glove box.

Thanks for you great customer support! In a day and age where customer service is computerized and non existant, it's a breath of freash air to see such support. :tup:
 

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Is 15psi safe to run without WMI?

The answer is probably depending on how the ECU MAP is set up. OE map will probably allow a bit of over boost if the condition is ideal and peg the boost down near the minimum (wategate setting) if time ate not going right. I cannot say if 15 is safe or not.

Failing to control boost during failsafe, I believe the ECU can adjust timing and fueling to combat the onset of knock of high inlet temperature. As far as I know the subaru only measures pre-turbo temperature.

If this is a grey area and not worth th riskm I would just go for the 9-19psi psi set up plus a g grimmspeed 3-port valve -no pill is needed and have excellent control range.

Alternatively, go for a 15 psi spring if you can ask your tuner to made a safe map at up to 15psi. If all is well with the HFS-3, you can run full boost with a leaner map.

The HFS-3 is only just available, so plenty of time to save up. The HFS-3 system is very well priced for a progressive PWN-valve based system.

I can't see any problems with front mount pump. Makes no difference. The only thing we will probably need to watch out, the pump is not 100% water proof. Keep it away from direct water splash. Controller in the glove compartment is perfect, ensure plenty of slack so the controller can be pulled out for future modification.

It is important for me to clear up any grey areas not fully understood on the HFS-3 sticky presentation.

Here is a link you can get some feedback from those who has purchased or installed the system.
Aquamist HFS-3 forum - waterinjection.info

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