Hello. I was wondering if the DOHC heads off my outback will fit a 2.5 block that originally was SOHC? Thanks for your time.
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Guest Message by DevFuse

EJ25 DOHC Heads on SOHC block?
Started by
[HTi]Johnson
, May 23 2007 02:30 PM
4 replies to this topic
#1
Posted 23 May 2007 - 02:30 PM
#2
Posted 24 May 2007 - 10:03 PM
Yes. Direct swap no problem.
#3
Posted 24 May 2007 - 10:07 PM
I think the combustion chamber is smaller on the dohc, so you'd have somewhat higher compression ratio after the swap.
#4
Posted 24 May 2007 - 11:57 PM
Nope just a difference in the pistons themselves but compatible all the same. SOHC pistons are higher compression.
#5
Posted 25 May 2007 - 12:39 PM
Your new compression ratio will depend on the gasket you use. I suggest a cometic 60 thousands. Should be around 10.6:1. should be good on 89 octane.
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