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99 legacy wagon and 98 OBS
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165 Posts
Discussion Starter #1
okay so i have a 99 legacy wagon with a phase two 2.2l with 2.5l heads on it, its slowly developing a knock.

my buddy is willing to sell me his 98 phase one 2.2 liter that was just freshly rebuilt about 10k ago. (roughly 120 total miles)

am i going to run into any trouble putting the phase two 2.5 heads on that phase one block? because my intake mani wont fit on the phase one heads. my car is MAP. has a different TPS, and has a IAC valve so i have to use the stock phase 2 mani.

just wondering if theres any problems with the difference in phases.

also plan on homebrew turboing this motor.

anyone got any input?

thanks
 

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95/99 Brighton STi
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2,945 Posts
yes you can use a p1 block with p2 heads. You'll just have less bellhousing bolts and one starter bolt instead of 2. I'm running a similar setup in that I have a p1 shortblock with p2 heads
 

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99 legacy wagon and 98 OBS
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165 Posts
Discussion Starter #4
okay thanks. thats what i wanted to know. what head gaskets did you use? p1 2.2 gasket or p2 2.5 gasket?
 

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95/99 Brighton STi
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2,945 Posts
Generally you would use the HG made for the shortblock but since you're using EJ25 heads, which have a wider head chamber compared to the cylinder bore, I'm not 100% sure. Usually when people have hybrid engines, the head chamber is narrower then the cylinder bore (might have something to do with why your original engine had problems).
 
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