Mountune extracts 684hp from 2.3 EcoBoost

Mountuneโ€™s US workshop reckons it has created the highest output all direct injection four-cylinder known to man off the back of Fordโ€™s 2.3-litre EcoBoost. The jig-tested motor has been pushed to 684hp, a gargantuan gain of 334hp over standard and 186hp more than Mountune's m520 pack, using primarily only a new head and larger turbo to achieve it.

While further details are yet to be revealed, Mountuneโ€™s new video shows that the motor peaks in power at about 6,900rpm (although it revs up to 7,200rpm during the run), while torque on the graph is shown to top out at 566lb ft at just over 5,500rpm. Those are stats worthy of supercardom; and to think that people still doubt the strength of the EcoBoost block after that head gasket production issue of 2016โ€ฆ

No doubt thereโ€™ll be a queue of Focus RS owners putting in their requests for Mountuneโ€™s 684hp work right now, although at this stage itโ€™s not clear whether the upgrade is heading towards customers or simply a simply a project to illustrate the extent engineers can go with a Ford four-cylinder motor. No less exciting is the prospect of a 2.3 as highly strung as this going into a future third party supercar; presently the readily available crate motor is used by the likes of Dallara and its Stradale with a comparably measly 396hp output.

Mountune obviously has a close working relationship with Ford, although the manufacturer is unlikely to turn to traditional tuning for its next step-up in output. Like its rivals, Ford is planning on utilising mild-hybrid tech to unlock more power in the next-generation RS five-door while trimming average CO2, creating a new drift mode rival to AMGโ€™s latest A45 and rumoured BMW M140e hybrid. Which is fair enough. Especially when it seems we can count on the likes of Mountune to keep it real.

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Comments (60) Join the discussion on the forum

  • Maldini35 5 days ago


  • RacerMike 5 days ago

    But.....but.....head deck.....arghhhh.....does not compute.

    All the haters are going to go absolutely mental over this laugh

  • David87 5 days ago

    Put it in the Ranger Raptor and take my money.

  • Gad-Westy 5 days ago

    “ Tuner's US workshop turns up wick a lot (a lot) to produce possibly the highest direction injection motor yet”

    Highest what? Size?

  • ecs0set 5 days ago

    It occurs to me that I find the prospect of a 684bhp turbo four significantly less interesting than a 250bhp N/A five or six. I think I may be getting old. Should I send back my PH card?

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