Aquamist HFS-3 High Flow Water Injection System Red Gauge

Part #: AQU 806 083RD
( 5 reviews )


MSRP: $753.00


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Out of Stock
Orders placed today should ship by 06/06/2016


Brand: Aquamist
Attachment Method: Hardware
Display: Red
Requires Control Unit: Yes (Included)
Tank Included: No
Volts: 12v
Gauge Sending Unit: Electrical
Gauge Size (mm): 52mm
Mfgr. Warranty: 1 year
Return Policy:

RallySport Guarantee - 30 Days

Items that are covered under the RallySport Guarantee offer a 30 day no questions asked return policy.

RallySport Guarantee items may be returned within 30 days of the original invoice date and must include all the original parts and contents for a refund.

The RallySport Guarantee does not apply to products that have been modified, damaged, misused or abused. All returns require an RMA (Return Merchandise Authorization) Number, and freight charges are strictly non-refundable. For more information regarding our freight refund policy, please refer to our return policy page found HERE.


Universal Product This item is non application specific.
Please verify compatibility before purchase. May require some modification for proper installation.

As water injection is playing a more and more important role in power tuning, there is more need to have a “fail-safe” mechanism in place to detect the presence of water, thus preventing the engine from damaging itself through excess heat causing the onset of detonation. DDS3 water flow monitoring system is designed to meet this criterion.

The latest DDS3 v8 hardware update allows the unit to work with virtually any water injection system on the market. The 52mm Dash Gauge can be configured to detect a very wide flow range thanks to the revised flow sensor translation software, supplying data to a high intensity 8-segment led Bar graph display. The turbine flow sensor has also undergone a major mechanical enhancement to increase its flow range. Extending the flow up from 450 to 1000 cc/min is only a few clicks on the Sensor Calibration (CS) trimmer.

Failsafe detection circuitry has also been upgraded, it can now read Fuel injector duty cycle as well as MAP sensor. This new feature allows the DDS3 to be integrated with many other non-Aquamist water injection systems on the market seamlessly, All materials used are still 100% Methanol and Ethanol compatible.

The complete kit comes with a water level sensor, a signal conditioning junction box, a turbine flow sensor and an industry standard 52mm dash gauge. The gauge is backlit, automatic dimming for night driving. The gauge is now so well equipped that one can build a complete single stage water injection system (p14) by just adding a water pump, a relay and a spraying nozzle, with absolute safety as standard.




The best WMI kit bar none.
daniel.lheman37093 3 months ago
I've seen most of the big names WMI kit and even had them installed on my cars. But when it comes to EJ257 STI engine I want the accuracy of Aquamist Injection Duty Cycle (IDC) trigger method than the simpler boost trigger method. Suffice to say, if you want to tune your engine to run with WMI then look no further because Aquamist is the only way to go. For example, on one very hot day my Aquamist system will inject close to maximum even though the boost was very little. This is thanks to IDC trigger responding to the Subaru ECU spraying fuel to cool down the engine under severe hot temperature. This also means the WMI amount is always accurate and always inject at the right time. In such situation, if I use boost trigger the WMI won't cool the engine when the engine really needs it since it must wait until the boost reach substantial level to permit near maximum injection. But by then it is probably too late. Installation is a bit more involving, especially since it must be hardwired to the ECU. And the FAV must be placed somewhere that is not too hot yet close enough to the intercooler. For TMIC application this can be quite tricky. If the FAV is too far from the nozzle, then there will be empty water line and can even result in air pocket in the water line. The solution: add Aquamist checkvalve close to the nozzle, or get their nozzle with build in checkvalve. This will keep the water line between the nozzle and FAV filled and no delay (though very little I assume) due to having to wait until the water filled the line before it finally reached the nozzle. So get the best - get Aquamist!

Aquamist HFS3
Brett.carlson33805153 2 years ago
I haven't seen any other WI kits, but when I opened the box for this one, I was pretty amazed. All of the pieces are high quality, and there is plenty of wire to reach just about anywhere on the car. The power wire from the pump the the battery was just long enough routing from the passenger trunk side, to the battery on the drivers side. The hardest part about the kit was deciding where to mount everything. I decided to go for a more factory look so everything is hidden except the pump. I mounted the FAV under the cover for the windshield wiper motors. Drilled a small hole through the bulkhead and routed the 4mm hose under the TMIC to the jet. The controller unit is mounted inside the glove box for easy access. Over all, I'm very impressed with this kit.
Verified Purchase
The only brand to go for
awangard.motors35013 2 years ago
Extreme quality item , co es with everything you will need for instalation. As previous rewiev says its wellabove other brands. money well spend

Man, What a system!
guest55c52bc6caae52790b8b8f2f 4 years ago
Ive installed a couple of meth kits in my buddies cars. I did an aem meth kit install and thought it was okay but as soon as I opened the box to this kit I KNEW it was the right choice for my sti. Every piece in there just screams quality! The gauge is beautiful and so well made. All the meth line connections are very sturdy and go together solid. I used my oem windshield washer bottle and it works beautifully! The brain unit taps into the wires at your ecu and bases the injection of meth off the injector duty cycle. What a system. The failsafe cuts boost down to wastegate pressure if there is a leak or clog or empty bottle and does not throw an engine light. Its simply amazing! This is THE kit to buy. I would recommend it to anyone.
Verified Purchase
Super easy install
STI-GUY 4 years ago
The new connections they added to the wires make install a lot easier then some of the older kits like the hsf5.


  • AnswerQ: Aquamist HFS-3 High Flow Water Injection System Red Gauge  Peshinho coob accessport v3 1 month ago

    Hello: I have a 2007 wrx and I want a meth kit. Do you recommend this one (HFS-3) or the HFS-2 or HFS-4 (this one I am not sure as I think it is for direct injection cars). Let me know Thanks Facundo

    • A: We recommend the HFS3v3 for your car. You are correct, the HFS-4 is intended to be used with DI cars.

      Tyler.G 1 month ago

  • AnswerQ: Droplet size  KornShaDoW097 7 months ago

    Hi, what is the droplet size rating of their injectors? I 'd say at 200psi and 175 psi? (In microns) thanks

    • A: Unfortunately Aquamist does not publish that info.

      Josh P. 7 months ago

  • AnswerQ: gauge  jrkingz4290870 12 months ago

    does aquamist sell just the gauge??

    • A: We do not carry the gauge by itself.

      Nick S. 12 months ago

    • A:

      rauderripper 7 months ago

  • AnswerQ: witch nozzle?  darin m 1 year ago

    how do you calculate witch nozzle to use? according to your set up, injectors and etc.

    • A: It is a somewhat involved mathematical equation that can be found online. The basic figures you would need to know would be Injector flow rate and peak boost pressure. If you have any further questions please contact us directly.

      guest55fc85a42a8d25a9578b4ffe 1 year ago

  • AnswerQ: EBCS and EWG  decodeddiesel19219 2 years ago

    Would the boost cut feature of the HFS-3 still function with a Grimmspeed EBCS hooked to Tial 38mm EWG? How about with an EBCS/Manual Boost Controller hybrid set-up? Thanks!

    • A: Yes, this would work with those set ups and it would be up to the tuner to ensure that they are all working together properly.

      Spencer H. 2 years ago