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EDM USDM JDM food for thought.


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I have been following topics on heads, headers, single and dual-ports, interference or not, etc etc

I have noticed that the USDM EJ22s from 95 on would have single port heads, coinciding with the start of the interference engines too. Is that correct?

Whilst my Fuji-built EDM Legacy from 96-97 would ‘appear’ to have the interference NA EJ22 (eg. solid valve tappets- I haven’t actually checked that yet), it does however have dual exhaust ports.

What other differences can we find?

The heads and headers on the 96-97 EDM NA EJ22:

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3D630624-11AC-4C26-B4C1-1E12FF703DC1.jpeg.8f366a1171da11bf14f6f0feac54a343.jpeg

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USDM EJ22 in 96 went to single port heads.

95 is still dual port.  Here, the 95 EJ22E, from an automatic car (with EGR) is the preferred direct swap for 96-99 EJ25D

As for Hydro/solid and interference, the solid here started in 97 and were interference.

It's hard to say really though, because I've seen JDM EJ20E heads that were roller follower, solid adjuster rockers.  And that was definitely an early 90s engine and non-interference.

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This is always something I don’t understand about the USDM single port heads - why go backwards like that if you’ve got the tooling for the dual port heads? 

I find the whole single port heads just at odds. We’ve got the dual port all the way through in our EJ engines. 

Cheers 

Bennie

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37 minutes ago, el_freddo said:

This is always something I don’t understand about the USDM single port heads - why go backwards like that if you’ve got the tooling for the dual port heads? 

I find the whole single port heads just at odds. We’ve got the dual port all the way through in our EJ engines. 

Cheers 

Bennie

its because Jap car companies hate USDM market :\

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18 hours ago, Jadu108 said:

its because Jap car companies hate USDM market :\

I think the word you are looking for is Japanese.

The other way you said it is often used as a slur, not likely to be appreciated here.

Also, USDM is their LARGEST and most profitable single market, I doubt they "hate it"   Much more likely that the single port is more to do with US emissions and efficiency regulation.  

Edited by FerGloyale
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Fair enough. Not intended as a slur, just a short hand that I will be sure to refrain from. My apologies to any offended.

And i meant it as a joke more or less about hating USDM market...
But realistically lets look at what the USDM market doesn't get compared to JDM or even AUDM

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AUDM doesn’t get half of the JDM goodies that are actually on offer. NZ gets many of them shipped over as second hand vehicles from what I understand. 

I also don’t know how the Siamese exhaust ports help with emissions, I thought they’d drop the required emissions  and that’s why they got rid of them! 

This could be a long shot - any models or parts made in the US - or is everything built in Japan and shipped stateside? 

Cheers 

Bennie

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SOA have a plant in Indiana where the *shudder* Baja was made. No idea about the engines or other machined items though, I'm guessing just sheetmetal pressing and assembly.

JDM stuff (real JDM, not just stuff that wasn't sold in the US, or Australia, etc) is pretty limited in Subaru-land compared to Toyota. I think even their Kei-cars were readily available in select markets - it's just Subaru offices choose not to import models based on perceived market demand (or in the case of Subaru Australia, it had to be AWD or they wouldn't sell it...the BRZ was a big decision to offer locally).

 

 

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5 hours ago, dfoyl said:

SOA have a plant in Indiana where the *shudder* Baja was made. No idea about the engines or other machined items though, I'm guessing just sheetmetal pressing and assembly.

JDM stuff (real JDM, not just stuff that wasn't sold in the US, or Australia, etc) is pretty limited in Subaru-land compared to Toyota. I think even their Kei-cars were readily available in select markets - it's just Subaru offices choose not to import models based on perceived market demand (or in the case of Subaru Australia, it had to be AWD or they wouldn't sell it...the BRZ was a big decision to offer locally).

 

 

All the Legacies/Outbacks/Bajas/Tribecas have been made in Indiana since 1995, and some of them earlier. Impreza/Forester are made in Indiana as of the last couple years.

That said, I'm under the impression that the engines are assembled in Japan and shipped over. But I'm not completely sure of that.

 

I'm also under the impression that interference and single port heads were not correlated, and the parts catalog says the pistons changed as of mfg date of 7/96.

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2 hours ago, Numbchux said:

I'm also under the impression that interference and single port heads were not correlated, and the parts catalog says the pistons changed as of mfg date of 7/96.

I would be interested to see if this is true.

As I have it understood, the hydraulic valve system is only found on clearance engines, correct?

Apparently (according to the dealer) my heads have solid adjustable valve tappets, but combined with dual exhaust ports.

 

 

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