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Old 07-24-2006, 10:16 AM   #1
Scooby Specialist
Member#: 1541
Join Date: May 2000
Chapter/Region: MAIC
Location: Fairfax, VA
2001 Lexus GS430
Black Onyx

Default Shortblocks does EJ20 = EJ25 = EJ257 fitment wise

I'm looking at a spun bearing / thrown rod in my 99 SF Forester. Since this is a daily drive I need something quick~n~fast (and preferably cheap) to get it rolling again.

Will any EJ shortblock bolt up to my exisitng heads (if they're not damaged as well), intake, AC compressor etc. without any issues ?

~ will using an EJ20 shortblock make the car a 2.0L (read WEAKER 145hp) motor than the stock EJ25 Phase2 SOHC that just died?

I'm also going to freshen the new longblock before it goes in should I add anything to this list:
~ timing belt
~ timing belt pulleys/rollers
~ timing belt tensioner
~ front/rear seals
~ water pump
~ head gaskets
~ ARP Headstuds

I'm just trying to figure out what I can get in there quick ...


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Last edited by BossGVR4; 07-24-2006 at 12:21 PM.
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Old 07-24-2006, 10:25 AM   #2
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Join Date: Aug 2005
Chapter/Region: W. Canada
Location: Winnipeg, MB
2005 2.5RS Wagon
Crystal Grey Metallic


In the engine designation EJxx, where xx is 18, 20, 22, 25 etc. that number determines displacement of the engine, so using an EJ20 bottom end you end up with a 2.0L motor. The heads should bolt up fine, and the intake manifold bolts to the heads so the block you use won't affect fit of anything before or after the heads. Not sure how it affects accessories though. Power output of the smaller displacement blocks will vary depending on whether you use the heads that come with that block, your existing heads from your EJ25, etc because combustion chamber volume varies which will in turn affect compression ratio. This can be compensated for with different thicknesses of headgaskets. Somebody on here should know the right combination that will work best for you if you can't find another similar EJ25 block to your original.
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Old 07-24-2006, 02:57 PM   #3
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Join Date: Dec 2000
Chapter/Region: MWSOC
Location: Cincinnati

You don't want an EJ20. The compression is lower...I doubt it puts out 145HP if you ran it NA...and I doubt you'd be able to do it without a custom tune/engine management option. So the costs option would be negated there.

An EJ251 should be easily obtainable. You need to make sure you get the same phase as what you had in before....no idea what '99 Forresters had, either Phase1 or Phase2. Those blocks should be pretty cheap, either way though. If you switch to another phase, there's a chance of having sensor issues. I'm not certain they're different...but it's something I'd verify before going outside of the stock option.
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