Do I need to install LS9 gaskets for my build?

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Jan 19, 2014 | 01:12 PM

BlkBird2000

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From: Wood River, IL

Do I need to install LS9 gaskets for my build?

I have a LQ4 with 317 heads and a ls6 intake that I will be boosting.

TC78 turbo 8-10 psi max
turbo cam
80lb injectors and dual fuel pump

Being as I am only going to go to 10psi max which should net me somewhere around 600hp, do I need to install ls9 head gaskets or will the factory gaskets work fine? LQ4 was installed before I bought the car. Far as I know the heads have never been off. I see guys that go upwards of 20 psi recommending the ls9 gaskets. Didn't think I would need them but wanted some input first before I ruled them out. Thanks.

Jan 19, 2014 | 01:30 PM

Exidous

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Factory gaskets are fine. At 10psi get the thickness for the CR you want.

Jan 19, 2014 | 01:45 PM

BlkBird2000

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From: Wood River, IL

I figure the compression for this motor was already pretty low. I rear also that head gaskets don't change the compression ratio.

Jan 19, 2014 | 06:57 PM

samdogmx

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If its already together I wouldn't pull it apart to change them. The LS9 will lower your compression even more and since you only want to to 10psi I'd say your fine with factory.

Jan 19, 2014 | 07:17 PM

crazyelf

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Ls9 gasket is the same compressed thickness as the other ls head gaskets and the bore size would only effect compression by a few hundredths. So I wouldnt sorry about that aspect.

Jan 19, 2014 | 07:36 PM

Twin turbo c5

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If its still together I'd run the factory one's. My 6.0 held the gaskets till I got to 22 psi with 179,000 miles on it . If not ls9 gasket it.

Jan 19, 2014 | 11:03 PM

BlkBird2000

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From: Wood River, IL

I appreciate the feedback. I thought the stock gaskets would be fine. I have no intentions to make more power than I am with this setup. Hope this motor will last a few years. If it ever does blow up I'll buy a forged short block and go from there.

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