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I5 Cast Inlet Plenum [Mk2 Focus RS/ST]

mountune's highly-skilled engineers identified an obvious performance and aesthetical improvement to all I5 engines through the creation of an I5 cast inlet plenum.

Extensive in-house CAD and CFD work (by the same team responsible for producing mountune's BTCC, WTCC, WRC and Rallycross inlets) allowed an improvement to be made - particularly around the port entrance to each inlet, as well as to increase the volume of the plenum itself to a more appropriate size for the 2.5-litre engine.

The mountune I5 cast inlet plenum has fast become the market-leader in the I5 cast inlet plenum sector with good reason; proven performance benefits across a multitude of power outputs, durable construction, OE packaging for ease of installation on mk2 Focus RS, mk2 Focus ST and various Volvo models - all combined with the assurance of buying from the best in the business and a name you can trust.

The I5 cast inlet plenum is supplied in an "RS500" crinkle black finish, and comes supplied with the required hardware for installation. Fitting takes less than 30 minutes on a mk2 Focus RS and approximately 60 minutes on a mk2 Focus ST (recommended removal of OE induction assembly).

Output improvements will vary on non-mountune upgraded vehicles, dependent on specification of tune, calibration and boost level being run.

Customer Reviews
4.8 Based on 26 Reviews
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Filter Reviews:
    John P.
    United Kingdom United Kingdom

    cast inlet plenum

    looks good but not fitted yet

    France France

    indispensable et fiable

    faire une préparation digne de ce nom mérite le meilleur et ce plenum en est digne il apporte toute l'efficacité qu'on lui demande, le montage est rapide et simple et apporte un vrai plus sur la préparation

    mountune I5 Cast Inlet Plenum [Mk2 Focus RS/ST] Review
    Aaron B.
    United Kingdom United Kingdom

    Great Part & Fantastic Service

    The I5 Cast Inlet Plenum [Mk2 Focus RS/ST] was as described, and is a very high quality part which looks and does exactly what is advertised. I had this fitted at Mountune’s HQ and the service there was second to none, very friendly, helpful and overall was a very enjoyable experience. 10 out 10.

    mountune I5 Cast Inlet Plenum [Mk2 Focus RS/ST] Review