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Old 11-05-2002, 01:51 PM   #1
andrewmva
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Default Will the EJ20 heads BOLT-ON to a EJ25 block??

if not what mods are needed????
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Old 11-05-2002, 02:52 PM   #2
HndaTch627
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yes they will. i am assuming you destroyed the bottom end of the EJ20 if you are now bolting them onto an EJ25.

Good Luck

jeremy

p.s.: use the head gaskets for an EJ25

Last edited by HndaTch627; 11-06-2002 at 12:54 PM.
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Old 11-05-2002, 04:03 PM   #3
rhdude
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FYI- you are going to choke that motor to death.....
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Old 11-05-2002, 07:42 PM   #4
tcs007
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Quote:
FYI- you are going to choke that motor to death.....
How you figure? I was under the impression the WRX heads flow more air than the 2.5 heads.
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Old 11-05-2002, 08:18 PM   #5
Impreza Rider
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You know...people keep saying the WRX heads don't flow as well as the EJ25 heads, but I have yet to see proof.
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Old 11-06-2002, 02:14 AM   #6
HndaTch627
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well boys FWIW the WRX heads flow worse on the bottom then the EJ25 heads, but on the top they outflow them tremendously. I'd be worried about the cam's not having nearly enough lift to power an EJ25.

Jeremy
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Old 11-06-2002, 02:42 AM   #7
STiTuner
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Quote:
Originally posted by HndaTch627
well boys FWIW the WRX heads flow worse on the bottom then the EJ25 heads, but on the top they outflow them tremendously. I'd be worried about the cam's not having nearly enough lift to power an EJ25.

Jeremy
would custom ground cams be enough to fix the issuse of lowend lack?

also I can understand flow being of importance but what about the fact that you have a bit more mechanical timing control witht eh WRX heads seeing as how they are DOHC. would it be worth it if you could find cams?

Brad
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Old 11-06-2002, 03:39 AM   #8
HndaTch627
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Quote:
Originally posted by STiTuner


would custom ground cams be enough to fix the issuse of lowend lack?

also I can understand flow being of importance but what about the fact that you have a bit more mechanical timing control witht eh WRX heads seeing as how they are DOHC. would it be worth it if you could find cams?

Brad
yes very much worth it, but only for a Turbo Application, it'd be a waste of time and money on an NA setup. with a set of custom ground cams w/ enough lift to feed and EJ25 you'd be set. you'd have an incredbile package.

Jeremy
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Old 11-06-2002, 04:20 PM   #9
crash
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Quote:
Originally posted by Impreza Rider
You know...people keep saying the WRX heads don't flow as well as the EJ25 heads, but I have yet to see proof.
Well, here's a comparison to the EJ22 Heads:

http://www.cobbtuning.com/tech/sohc/page2.html

-Nathan
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Old 11-08-2002, 10:56 AM   #10
omahasubaru
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You could look into MY98 EJ25 DOHC cams... those might work with your WRX heads.

Jon
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Old 11-08-2002, 04:12 PM   #11
akcel
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Quote:
Originally posted by crash


Well, here's a comparison to the EJ22 Heads:

http://www.cobbtuning.com/tech/sohc/page2.html

-Nathan
ej22 heads dont compare to ej25 or ej20 heads lolz
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Old 05-09-2021, 12:32 AM   #12
justrunnin
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Quote:
Originally Posted by HndaTch627 View Post
yes they will. i am assuming you destroyed the bottom end of the EJ20 if you are now bolting them onto an EJ25.

Good Luck

jeremy

p.s.: use the head gaskets for an EJ25
Just wondering, if it was the other way around (ej25 dohc heads on a ej20 dohc) would you run the ej20 head gasket?
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