Short Block PN's ??

[B-BGTLimited]

So what's the best, or differences between some of the OEM short blocks out there that are available from Subaru.

 

MaxCapacity's thread noted this PN: 10103AC050

 

When searching for that you can find some results and sales for that PN, but some Subaru site's say it's been superseded by PN: 10103AC890

 

And when I look up an 06 Legacy GT, I get PN: 10103AC870

 

Anyone have any clue what the difference is between these three? And if there is a better PN out there? I know some have different CR's and I wasn't sure what was the best option for crank, rods and piston combos.

 

Plans for the build is a OEM short block, best one, stock heads, VF52 turbo and it will have the Invidia turbo back exhaust, and Perrin TMIC from my 07 when finished. So nothing overly special, this is my daily. I'm expecting to run a similar 18-19PSI tune that I have on my 07 that netted me 255whp 310ftlbs on a stock VF46.

 

I bought a whole 06 LGT to replace my badly rusting 07 and the previous owner appears to have driven it longer than he should have... Crank is junk, 1 rod gone, cylinder 2 has scratches in the wall, and the worst part is it spread metal through the whole engine so unless I can find someone who can magically repair the cam bores (and I have to replace the cams) then I need two new heads to go with this setup as well.

 

I'd post up pics, but the attachment manager is not working, and I don't use photobucket anymore. Maybe I can get them through tapa talk on another post.

[B-BGTLimited]

Pics via tapatalk.

 

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[Max Capacity]

Hi there, you've been gone for a while, welcome back.

 

There is a newer version which is the RA block, it has different piston skirts if I recall.

 

For your HP goals you'll be fine with whatever EJ257 short block you get. I recall being told you will get the latest version Subaru is building.

 

remember to get the engine gasket set for your year car.

 

FWIW, my 257 is still running great and very quiet for a EJ.

[B-BGTLimited]

Yes, yes I have Things got busy with my move in 2018 as well as buying a GM concept car... I've been pretty MIA on all forums lately including the Beretta ones.

 

Any motor will be quieter than my .020 over CP Forged piston motor... lmao

 

Regardless of what PN I purchase it should be the latest version? Is that if I buy from a Subaru dealer? I have to assume stuff you see on Amazon or Ebay is something that they have had on the shelf, and that begs to ask the question of am I better off buying it through a dealer to ensure that Subie freshness is there?

 

Also any idea why the 10103AC890 PN says it "doesn't fit" an 06 Legacy, and the fitting short block is the 10103AC870 PN? There has to be something different between the two. I know the 890 is listed as the STI build, is it perhaps a lower CR, larger dish pistons, to accommodate the larger STI turbo and higher boost levels?

[B-BGTLimited]

Shit just found this info on the RA block... this is the most info I have found regarding how these are put together..

 

https://www.importimageracing.com/products/subaru-oem-2-5l-shortblock-subaru-sti-type-ra-2018-sti-2020?gclid=CjwKCAiAt9z-BRBCEiwA_bWv-ByWVzBcqydOIctB7oaKXODDfE9rqWrOkFDipOgU4HoBubAJsb4prxoCjtcQAvD_BwE

[Max Capacity]

I can give you my contact, the Part Manager at my local dealer if you want to get good customer service and buy the latest Subaru has to offer, they are in Manchester CT. PM me if you want to contact him.

 

Any Ej25 block will be the same basic size.

 

The change in compression ratio will have no effect on fitting what you need.

[Chocoholic005]

Holy excessive fujibond!

[B-BGTLimited]

You should have seen the valve cover gaskets... insane amount used, I was expecting to find it blocking the oil pickup but it wasn't.

 

There has been a lot of subpar work found on this build... Sadly it's going to cost a bit more than I was hoping to get a new daily out of this, but hey it's still cheaper than a new car and insurance for that!

[ashwinearl]

Here are some notes I have when I was considering new short block last year. I have a 2005 Legacy GT Wagon. Confirm with a dealer or performance shop.

 

The Type RA is what I was going to go with, but some sellers will say they won't honor a warrantee if the shortblock doesn't map to your VIN #.

 

2004-07 STI Shortblock: 10103AC870 - This one EJ257 matches my VIN

 

2008-16 STI Shortblock: 10103AC890

 

2006-14 WRX/FXT/OBXT Shortblock: 10103AC880

 

10103AD020 type RA

 

Heuberger Subaru typically had the best price on a shortblock, or similar dealer who sells online.

[B-BGTLimited]

Yeah I was wondering about the whole warranty deal.... I honestly wonder how much that will matter since it's going in a car that will have a custom tune, VF52, full exhaust and I'm doing the build and install... Not many places honor their warranties if it's being done by a DIY and not in a shop.

 

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[seanyb505]

Yeah I'd forget the whole warranty thing once you go off the dealership-installed path. Having said that, I called heubeger to order my short block. I told them what I was doing - generic build for an 05. I can't remember the exact part number, but they helped me understand why calling to order an ej255 unit would end up with me getting a newer ej257 part.

 

It made me feel I was getting what I needed rather than whatever parts catalog led me to order. I'm sure there are knowledgeable techs around the country that can walk a decent shadetree mechanic through that process. Heubeger has done a good job of making themselves available to a group of people building 10yo cars.