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Head Gasket question

Old Nov 22, 2018 | 09:19 AM
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Default Head Gasket question

Good Thanksgiving day forum members,
Rebuilding my LQ4 to be punched 030 over and not sure which head gaskets covers the bigger bore correctly?

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Old Nov 23, 2018 | 06:24 AM
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Anyone?
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Old Nov 23, 2018 | 07:52 AM
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Do you want GM or aftermarket?
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Old Nov 23, 2018 | 03:09 PM
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Prefer GM MLS offerings.
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Old Nov 23, 2018 | 03:12 PM
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LS9 is hard to beat for price and performance, provided your block and heads are MLS capable.
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Old Nov 23, 2018 | 03:34 PM
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Its a LQ4 am rebuilding which will be bore 030 over. I'll be utilizing the original 317 heads until i can upgrade if needed at a later date. Am concentrating on a good bottom end which will include a Wiseco pro tru piston kit. Not sure which head gasket to use due to the new bore size and i'd like to be at pump gas compression ratio.
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Old Nov 23, 2018 | 05:08 PM
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Well what cc pistons? How far out of the hole? 317 head is basically 71.5cc

pump gas as in 93 oct? What’s available near you.
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Old Nov 23, 2018 | 08:12 PM
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This is the WISECO piston kit specs, depending on the correct head gasket will determine my compression ratio.
With your recommendation it appears a 10.5 ratio....am good with that if this is the head gasket? GM12622033

Part Number:WISESCO-PTS523A3
Bore (in):4.030 in.
Bore (mm):102.362mm
Piston Styleome, with two valve reliefs
Piston Material:Forged aluminum
Compression Height (in):1.335 in.
Piston Head Volume (cc):-4.00cc

Last edited by Ecrod103; Nov 23, 2018 at 08:59 PM.
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Old Nov 23, 2018 | 10:49 PM
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I'd run that on pump gas all day. LS2s are 10.9:1 and run pump gas
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Old Nov 25, 2018 | 04:03 PM
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Originally Posted by Ecrod103
This is the WISECO piston kit specs, depending on the correct head gasket will determine my compression ratio.
With your recommendation it appears a 10.5 ratio....am good with that if this is the head gasket? GM12622033

Part Number:WISESCO-PTS523A3
Bore (in):4.030 in.
Bore (mm):102.362mm
Piston Styleome, with two valve reliefs
Piston Material:Forged aluminum
Compression Height (in):1.335 in.
Piston Head Volume (cc):-4.00cc

I would take that with a grain of salt. It’s likely less than what is shown due to the head gasket bore, which is larger than the piston bore and often lowers compression.

A ls9 gasket has a bore of 4.100.

Your compression is likely closer to 10.0:1 but should perform well.
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