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Old 09-09-2010, 12:18 AM   #1
meo
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Default Which gaskets?,2010 sti short block with 04 wrx heads

so im putting a 25 shortblock in my car 04 wrx heads Just wondering what you guys think are the best choice of head gaskets? and what size as welll

I would like to use cosworth but i was told 60mm would be the best, however cosworth does not make 60mm
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Old 09-09-2010, 09:43 AM   #2
rexworx
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Well you have a few options.

first is use a OEM sti hasket. Your comp will be high.

next is to use a 0.051 cometic head gasket to bring the comp down to about 8.5-1

The best thing to do is have the combustion chamber on you cylinder heads to 2.5 bore spec. This is the best option but also costs the most...
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Old 09-09-2010, 08:45 PM   #3
TRDRacer
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Cometics have no firering on there gaskets which is why many have problems blowing them up! Cosworth would be close to the 1.1mm which would give you a closer ratio as a real STI but then you run a chance of poping them cause they are so thich.

If you look up under my name I have a post that states what gaskets to use on a simial motor and a link to a compression calculator to get you the right thickness!
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Old 09-10-2010, 01:51 AM   #4
Strider327
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The one you want is the 20000916 part number from Cosworth. DO NOT Cometic.
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Old 09-13-2010, 04:35 PM   #5
meo
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why not go cometic? can anyone comment on this?
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Old 09-13-2010, 04:51 PM   #6
meo
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im pretty sure im gonna go .80 cometic... i think 1.1 will be over kill
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Old 09-13-2010, 11:47 PM   #7
sense of nature
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Just do the 1996-1998 2.5 DOHC oem head gasket..it's thicker than the STI & will help keep the comp down...DO NOT USE THE COMETIC......YOU HAVE BEEN WARNED
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