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Auxiliary Cold Air Intake (ACAI) [Mk8 Fiesta ST]

The mountune Auxiliary Cold Air Intake (ACAI) offers multiple airflow and aesthetic enhancements for owners of Mk8 Fiesta ST.

The all-aluminium ACAI assembly replaces the plastic air guide, which can either brake or sag behind the grille and improves upon the complex pathway that the air normally enters the induction system, with a pair of flow-optimised deflector scoops.

This ensures you get more cold air going into your OE intake crossover pipe, whilst blocking a minimal surface area of the radiator and causing a negligible affect on the radiators performance, unlike some larger standalone scoops.

In addition, we’ve then added an auxiliary air intake which can be used for multiple purposes; either with the supplied air feed hose and aluminium joiner to neatly connect with a mountune induction kit lower shanon hose (which provides an enhanced cold air feed from the front of the car) or alternatively, can be used to channel cold air directly onto our forthcoming inner-wing-mounted oil cooler kit.

Engineered to work in harmony with the mountune intercooler (not compatible with full-height intercoolers), the ACAI upgrade allows for enhanced airflow and cooling in multiple configurations, regardless of the induction system you are using.

Take advantage of our cooler combo and save 10% on both the ACAI and our high performance intercooler when purchased at the same time. Just use code gowiththeflow

Go with the flow

Not only does the ACAI give you two carefully flow-optimised cold air feeds to the OE airbox feed, we've also added an auxiliary scoop which can be used to feed either our forthcoming oil cooler kit, or joined to the porous lower hose supplied as part of the mountune induction kit setup, or even directed to a third-party intake.

Nothing else offers the same level of enhanced cold air optimisation, whilst crucially not inhibiting airflow to the radiator #gowiththeflow

Airflow, where you need it

The ACAI auxiliary scoop can be easily connected to an existing Shanon hose (found in all current mountune induction kits and our forthcoming open cone filter kit) with the supplied hose and aluminium joiner as shown, or to feed a third-party induction kit, or to directly channel cold air onto our forthcoming inner-wing-mounted oil cooler kit.

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5.0 Based on 21 Reviews
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Filter Reviews:
    United Kingdom United Kingdom

    Excellent upgrade for the car replaces a plastic OEM part discreet and great looking at the same time attached the hose for the induction kit and it’s a great combination. The build quality is again excellent. Worth every penny looked at the alternatives and this was the one for me, follow the fitting guide take your time with the bumper and it’s quite easy to fit too loving the mk8 even more now since I put tasty Mountune upgrades on it .

    Ryan W.
    Australia Australia
    Outstanding bit of kit

    Another awesome quailty product from Mountune. Combined with my ACAI its a winner. The induction roar is enhanced enough not to be annoying. The flutter sounds mean and purposeful.

    mountune Auxiliary Cold Air Intake (ACAI) [Mk8 Fiesta ST] Review
    Australia Australia
    Outstanding bit of kit

    Fitted this at same time as my MT intercooler, MT charge pipe upgrade, MT induction kit and MT throttle body elbow. I been a busy boy haha. As always Mountune's quality and OE fitment is next to none. The stealthy appearance they give is what I love about it, if you don't know what your looking for you wouldnt know it has been modified . The car is so much more potent now, since I fitted all the mods in one go. One last thing to bring it all in perfect harmony is the M235, which I will be lookong into real soon. Keep up the outstanding work Mountune.

    mountune Auxiliary Cold Air Intake (ACAI) [Mk8 Fiesta ST] Review