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Old 06-07-2013, 09:58 PM   #1
SimpleWrx
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Default 2.5 heads on a 2.0 block.

So I have the opportunity to get my hands on a set of 2.5 heads. Has anyone put them on a 2.0 block? Kind of interested in the head ache it might cause.
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Old 06-08-2013, 01:29 AM   #2
blubug_768
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It would probably lower compression. 2.0 heads work on a 2.5 because you can machine them out, you cant go the other way.
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Old 01-24-2014, 01:13 PM   #3
novacivic
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Will not work because the chamber is too wide on the 2.5 head compared to the 2.0 block and the head gaskets will not seal properly
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Old 01-24-2014, 02:21 PM   #4
2011WRXMT
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Originally Posted by novacivic View Post
Will not work because the chamber is too wide on the 2.5 head compared to the 2.0 block and the head gaskets will not seal properly
It will work this is what I think is called a hybrid build. Talk to your tuner or subi shop about it OP.
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Old 01-24-2014, 02:26 PM   #5
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Originally Posted by 2011WRXMT View Post
It will work this is what I think is called a hybrid build. Talk to your tuner or subi shop about it OP.
No it won't work, you can't put larger diameter combustion chambers on a smaller cylinder block. It work the other way around, you are confusing the two
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Old 01-24-2014, 02:44 PM   #6
2011WRXMT
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Quote:
Originally Posted by shagfagon View Post
No it won't work, you can't put larger diameter combustion chambers on a smaller cylinder block. It work the other way around, you are confusing the two

Oops my bad. Ill flame myself
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Old 01-24-2014, 03:06 PM   #7
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Stay away from any tuners that encourage this setup
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Old 01-24-2014, 07:42 PM   #8
_booSTIn_
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You would need to do 1 of the following to properly make a hybrid. JE FSR hybrid pistons, designed for 2.5 sb with 2.0 heads. Or you can machine the heads to match the sb
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Old 01-24-2014, 07:43 PM   #9
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Quote:
Originally Posted by _booSTIn_ View Post
You would need to do 1 of the following to properly make a hybrid. JE FSR hybrid pistons, designed for 2.5 sb with 2.0 heads. Or you can machine the heads to match the sb
read your post wrong. It won't work
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Old 01-29-2014, 12:55 PM   #10
dirtyscooby169
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if u wanna sell these heads let me know
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Old 08-03-2020, 02:46 PM   #11
DrewFoxWRX
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Originally Posted by SimpleWrx View Post
So I have the opportunity to get my hands on a set of 2.5 heads. Has anyone put them on a 2.0 block? Kind of interested in the head ache it might cause.
I’m using that build right now. Haven’t had any issues with it. Stage 1 going into stage 2 now
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Old 08-03-2020, 09:46 PM   #12
Shik
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Originally Posted by DrewFoxWRX View Post
I’m using that build right now. Haven’t had any issues with it. Stage 1 going into stage 2 now
Are you sure you didn't put machined 2.0 heads on a 2.5 block?
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Old 09-01-2023, 05:40 AM   #13
K0D3IN3
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Originally Posted by DrewFoxWRX View Post
I’m using that build right now. Haven’t had any issues with it. Stage 1 going into stage 2 now
That’s what I’m running at the moment as well did you run into a cylinder 3 misfire
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