Aquamist HFS-3 High Flow Water Injection System Red Gauge

Part #: AQU 806 083RD
( 4 reviews )


MSRP: $753.00


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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.




Aquamist HFS3
Brett.carlson33805153 1 year 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 3 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: Droplet size  KornShaDoW097 4 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. 4 months ago

  • AnswerQ: gauge  jrkingz4290870 8 months ago

    does aquamist sell just the gauge??

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

      Nick S. 8 months ago

    • A:

      rauderripper 4 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.

      1 year ago

  • AnswerQ: EBCS and EWG  decodeddiesel19219 1 year 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. 1 year ago

  • AnswerQ: differences?  j_currie1761790 2 years ago

    hi there why would a guy choose this kit over the aem 35psi kit? seems to me they are very relative in function?

    • A: The main difference is Aquamist uses pulse width modulation pumps, which provide better atomization, better consistency and quicker response.

      Zach G. 2 years ago