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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 | 18 Q&As
Part # 10103AC870
$2,285.71

In stock!

Features & Product Details

Knock Knock? Who’s there? Rod! Sorry Rod, but we just got a new OEM Subaru STI Shortblock! 

That’s right, this is a brand new fully assembled Subaru STI OEM Short Block so you can get back on the road, and back to brapping.
The Subaru STI shortblock includes all new guts which include a new crankshaft, bearings, rods, pistons, and main seals. You would just need to bolt on your heads, accessories, fill up with proper fluids, and you’ll be back on the road. 

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:

RallySport Guarantee - 30 Days


Items that are covered under the RallySport Guarantee offer a 30 day no questions asked return policy.

RallySport Guarantee items may be returned within 30 days of the original invoice date and must include all the original parts and contents for a refund.

The RallySport Guarantee does not apply to products that have been modified, damaged, misused or abused. All returns require an RMA (Return Merchandise Authorization) Number, and freight charges are strictly non-refundable. For more information regarding our freight refund policy, please refer to our return policy page found HERE.
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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  4 years ago
5out of 5stars

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 5 years ago
5out of 5stars

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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4 of 4 people found the following review helpful
2004 STI SHORT BLOCK 5 years ago
5out of 5stars

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 Hermes6 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 Dimick7 months 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 1 month ago  
        
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  • Q: 05 legacy gt  Surfstud01010 months 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 10 months ago  
        
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  • Q: Bolt Together Ready?  Cheapest_LGT 10 months 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 10 months ago  
        
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  • Q: 04 sti, piston,  Hmbasir2 years ago

    I am thinking of buying this block, I like that fact that it has forged rodes. I was wondering if rallysport has a OEM build with forged pistons as well. As that is a very common problem with the 04 sti, I wanted to have a longer lasting engine. Thank you for you answer back.
    • 0 of 0 people found the following answer helpful

      A:  The closest block that we carry to what you're looking for would be the IAG Stage 1 block, which features the same crank and rods as this block, but with upgraded bearings and forged pistons.

      Marcus E. @ RallySport Direct 1 year ago  
        
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