recommendations on best EJ motor for NA application?

Discussion in 'Modifications & DIY how-to' started by ihavefat, Nov 28, 2014.

  1. ihavefat

    ihavefat Member

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    Just toying with the idea of doing a subaru motor swap in a project car but first I wanted to do a thorough research on the EJ motors.

    Goal:
    - 150-200 hp
    - naturally aspirated
    - the less it weighs, the better
    - the smaller, the better


    My guess is even if it doesn't make 'goal' hp, with boltons it will make close to what I am looking for. Not looking to do a crazy build here, just wanting to know an affordable and reliable motor for a swap. I will probably get my hands on a high mileage/used or the ones with head gasket issues or sonething and fix it up. The cheaper, the better without sacrificing performance.

    High revving is preferable as well but not sure if that can be just easily adjusted with engine management.

    So far the most common seems to be the EJ20. I know there are other EJ motors that will make more power but the size/weight/cost is all a factor here!

    I tried researching this but no success so far. If this has been brought up, please guide me in the right direction!
     
  2. Matt

    Matt Think before you post
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    there was no USDM EJ20 that was n/a. Your best bet is the EJ25 found in the 2.5RS or Legacy.

    Subaru and high revving.... doesn't really exist. The 2.5RS topped out at around 6250. It might be possible to get up higher, closer to 7k at the most. but even then, it's not exactly good for the motor.
     
  3. ChrisW

    ChrisW Member

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    Ej204, dohc naturally aspirated with AVCS. Best 4 cylinder NA motor from the factory. I know where one is, not sure what all it comes with but you would still need the full harness and computer for it to run.

    Ej25d would be easier to source and its available in usdm cars.
     
  4. JWX

    JWX Member

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    Yeah, I'd say 25d hands down for something you'd find in the states.
     
  5. ihavefat

    ihavefat Member

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    Hmm true. I was thinking FA20 but I know it's just a completely different motor (internals/etc) despite the similar specs like the EJ 2.0s

    Is there a reason why you say the EJ204 is the best? how much does one go for?

    Is there a difference between EJ25 and EJ25d?
     
  6. ChrisW

    ChrisW Member

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    204 is around 190hp and has avcs, I'd imagine it would go for 8-1100 dollars but it's a complete dressed engine.

    There is actually no such thing as the ej25, that's just a common way to refer to 2.5l motors. There's the 25d, 251, 253, etc.
     
  7. ihavefat

    ihavefat Member

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    Ah gotcha. Was not aware that was just a generic name.

    Is ej25d the modt recommended one or really any of the ej25 will do? There is a guy selling ej251 that has about 110k miles and supposedly it was running before he took it out
     
  8. Matt

    Matt Think before you post
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    IIRC, the 251 is the DOHC version that has headgasket issues. That may also be the 25d, but not sure.
     
  9. b reel

    b reel Active Member

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