2.5 Turbo pistons in an EJ22T?

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my3awds
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2.5 Turbo pistons in an EJ22T?

Post by my3awds »

Hi this is my first post and I'm fairly new to the EJ engines so please be kind lol.

I will be sending an EJ22T shortblock to the machine shop soon to freshen everything up since I don't know how many miles are on this thing, before dropping it into my Impreza. What I was wondering is if the EJ25t pistons from say a 2004-2006 STi or even just aftermarket Wiseco 2.5 turbo pistons can be used on a bored out EJ22t block?

I did some research and it looks like all the EJ engines share the same stroke, just different bore. If this is the case, I'm assuming the closed-deck 22 shortblock might have enough wall to overbore a standard-size 2.5 piston. Has this been done before? Are the bris pins the same? I plan on just reusing the stock rods that are in there now if they are in good enough condition. If not, then I'll just save my money and go with some cheap TOPLINE piston 2.2 replacements.

Thanks for any advice.

Manny
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Post by DLC »

it may be technically possible to take the 2.2 to 2.5, but that could be near or exceeding what is possible. There are companies that can or do make forged pistons for these engines.
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Matt Monson
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Post by Matt Monson »

2.5l stroke is 4mm longer than Ej20 and Ej22. And to punch an Ej22 out to the bore of an Ej25 would require cutting out the sleeves and welding in all new sleeves. As Dave mentioned, you are better off just buying 2.2l forged slugs.

You can use a 2.5l crank to stroke an Ej22, but it only gets you to 2.35l...
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my3awds
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Post by my3awds »

Oh ok. Thanks for the clarification. I'll stick with a standard 2.2dohc build then.

Manny~
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