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Ptv clearance and comp ratio. Lq4 milled 243 heads

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Old Aug 3, 2019 | 09:21 PM
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Default Ptv clearance and comp ratio. Lq4 milled 243 heads

just ordered a tick towmax stage 2 214/224.571"/.561" LSA114+4 for a 05 lq4 that I’m swapping into my 05 Silverado 1500

i plan on getting a set of 243 heads and milling them to bump the compression as close to 11:1 as I can without running into clearance issues. I plan on using the stock mls gaskets .051” thickness.

Will i I be safe knocking .030” off of them without ptv issues and can anyone tell me what comp ratio would be with that setup?
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Old Aug 4, 2019 | 11:19 AM
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Did my 243’s .30 on a 232/234 cam on my lq4 and it’s fine. Cr should be around 10.7:1 if you mill heads that much
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Old Aug 4, 2019 | 02:57 PM
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PTV issues are driven more by duration than lift.


You’re fine.
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Old Aug 5, 2019 | 11:28 AM
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The LQ4 has the dished pistons, should be good to go.

Ptv clearance and comp ratio. Lq4 milled 243 heads-qiaesjj.jpg
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