Look On My Subaru Hood Scoop, Ye Mighty, And Despair

How much air could a ram air intake ram if a ram air intake could ram air? The question has long mystified scientists, so the folks at Garage 54 decided to test it out the only way they know how: Experientially. By which I mean they replaced the turbo on a Forester XT with a massive intake in hopes of matching boost pressure with ram-air force alone. Heroes.

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The intake, which sits nearly at the width of the grille and the height of the windshield, is meant to replace a comparatively small turbo. Yet, even with that size mismatch, the force of moving air alone is only barely enough to power the car — not nearly enough to match the turbo’s pressure.

We make a ram air intake for a Subaru – will it work?

Should you pull the turbo off your car and replace it with a massive amalgamation of sheet metal? No. Do not do this. It will not benefit you in any way and will probably just harm your engine. For you naturally aspirated folks out there, though, the benefits may be real.

See, comparing what is effectively a wood chipper chute to a turbo is a fool’s errand. Comparing it to a turbo car without its turbo, though, allows you to test boost pressure relative to NA operation — where the massive intake does, in fact, make a difference at speed.

So, if your turbo car isn’t fast enough, this won’t help. If your naturally-aspirated car needs a helping hand at highway speeds, though, the massive intake may actually be a boon — provided you can somehow tune that effect into your fuel injectors. Just, maybe build yours out of something transparent if it’s going to be this big.