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Subaru OEM STi Short Block - Subaru Models (inc. 2004-2007 STI)
Subaru OEM STi Short Block - Subaru Models (inc. 2004-2007 STI)
Subaru OEM STi Short Block - Subaru Models (inc. 2004-2007 STI)
Subaru OEM STi Short Block - Subaru Models (inc. 2004-2007 STI)
Subaru OEM STi Short Block - Subaru Models (inc. 2004-2007 STI)
Subaru OEM STi Short Block - Subaru Models (inc. 2004-2007 STI)
Subaru OEM STi Short Block - Subaru Models (inc. 2004-2007 STI)
Subaru OEM STi Short Block - Subaru Models (inc. 2004-2007 STI)
Subaru OEM STi Short Block - Subaru Models (inc. 2004-2007 STI)
Subaru OEM STi Short Block - Subaru Models (inc. 2004-2007 STI)
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User Media for: Subaru OEM STi Short Block - Subaru Models (inc. 2004-2007 STI)
User Media for: Subaru OEM STi Short Block - Subaru Models (inc. 2004-2007 STI)
User Media for: Subaru OEM STi Short Block - Subaru Models (inc. 2004-2007 STI)
User Media for: Subaru OEM STi Short Block - Subaru Models (inc. 2004-2007 STI)

Subaru OEM STi Short Block

Subaru Models (inc. 2004-2007 STI)

Read 3 Reviews | 19 Q&As
Part # 10103AC870
$2,285.71

Only 1 left!
Ships today if ordered in
6 hrs 29 mins
ANY QUESTIONS?

Features & Product Details

Sometimes life gives us our fair share of oops. Whether if you thought it was a good idea to boost without a tune, to boost without proper fuel mods, or if you lost to an Evo, RallySport Direct has the right tools, the right parts, and especially the right short blocks to get you back on the road. This is a great OEM factory stock replacement short block for your 04-07 Subaru STI!

On this page, you are looking at the Subaru OEM 2.5L EJ25 STI Short Block. This is a fully assembled short block that includes all the main guts such as the factory pistons and rods, as well as the crankshaft and main seals to make it ready for the installation. You or your preferred mechanic would have to bolt on the heads, oil pan, and fill it with the proper fluids to make your vehicle roadworthy again. 

Specifications

Brand: Subaru OEM
Assembly: Assembled
Bore Size (mm): 99.5
Compression Ratio: 8.2:1
Crank: OEM Forged
Crank Size: OEM
Displacement: 2.5L
Piston Material: Cast Aluminum
Power Output Rating (BHP): 305
Rods: OEM Forged
Mfgr. Warranty: No Warranty
Condition: New Product
Return Policy:
Standard

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REVIEWS & CUSTOMER MEDIA

3 Reviews
5 out of 5 Stars
5 Stars
(3)
4 Stars
(0)
3 Stars
(0)
2 Stars
(0)
1 Stars
(0)
Customer Photos and Videos
Subaru OEM STi Short Block ( Part Number: 10103AC870)
Subaru OEM STi Short Block ( Part Number: 10103AC870)
Subaru OEM STi Short Block ( Part Number: 10103AC870)
Subaru OEM STi Short Block ( Part Number: 10103AC870)
back on the road  5 years ago
5out of 5stars
Rob Mac
Needed to get the subie back on the road quickly as possible and this was perfect. Plus with no core exchange I still have my original block I can tinker with. Shipping was crazy fast and I was back on the road within days
  
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4 of 4 people found the following review helpful
2004 STI SHORT BLOCK 6 years ago
5out of 5stars
2004 STI
Came packaged very nice, assembled engine machine work was spot on. Engine now has 400awhp and 4800 miles very good no blowby I am pleased!
  
Was this review helpful?
4 of 4 people found the following review helpful
2004 STI SHORT BLOCK 6 years ago
5out of 5stars
2004 STI
Came packaged very nice, assembled engine machine work was spot on. Engine now has 400awhp and 4800 miles very good no blowby I am pleased!
  
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QUESTIONS & ANSWERS

  • Q: STi Short Block  Tyler Hermes12 months ago

    I need a new short block for my 05 LGT. Does this short block come with all the gaskets and bolts needed? Or do I need to buy those seperately?
  • Q: 2005 2.0L wrx  Jackson Dimick1 year ago

    Will this fit a 2005 wrx that originally had the 2.0L in it? I’ve heard of hybrid builds, 2.5L block with 2.0L heads, but will it be direct bolt on with the trans and heads?
    • 0 of 0 people found the following answer helpful

      A:  The heads will need some machining to work on the 2.5 liter block, but everything will bolt up.

      Lane H. @ RallySport Direct 8 months ago  
        
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  • Q: 05 legacy gt  Surfstud0101 year ago

    Would this block work with my 05 legacy gt?
    • 0 of 0 people found the following answer helpful

      A:  You bet, Subaru only confirms this for the STI, but the 257 is a pretty popular swap in the 2.5 WRX and Legacy's. Thanks!

      Rick C. @ RallySport Direct 1 year ago  
        
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  • Q: Bolt Together Ready?  Cheapest_LGT 1 year ago

    This block is completely preassembled with no machining required? Just crank it over when the block is in the Car? Or is there something that is needed in within this product like crank polishing?
    • 0 of 0 people found the following answer helpful

      A:  Yep, this is assembled from Subaru and ready for you to bolt on your fresh heads on, oil system, timing, accessories etc.. Do note this is literally the same block that came out of your car, so if you're going for big power, I would recommend other options like an IAG short block :) Let us know if you have any questions. Thanks!

      Rick C. @ RallySport Direct 1 year ago  
        
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