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compression question

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Old Dec 14, 2007 | 02:00 PM
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What is the most compression you can run on 93 pump gas??

I'm trying to decide on which way to go with my LQ4 and this is one thing I needed to know.

thanks
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Old Dec 14, 2007 | 02:03 PM
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i think taht depends on timing, cam and a few other things if im not mistaken
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Old Dec 14, 2007 | 02:18 PM
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Would 10.6:1 be safe enough to say there shouldn't be a problem?
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Old Dec 14, 2007 | 02:32 PM
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you cant just throw heads at a motor and expect it to work. you can run 12.0:1 compression on 93 octane if you set it up correctly. your static compression doesnt matter much when it comes to gas grades. your dynamic compression ratio is what your looking at when trying to stay within pump gas limits. your cam plays a huge part in this. shoot for an 8.7 dynamic compression ratio to max out 93 octane and be safe.

mine worked out to 11.0:1 compression, 8.7 dynamic compression with a 226 cam on XER lobes. call up WCCH or patriot performance and they can get you going in the right direction.
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Old Dec 14, 2007 | 04:00 PM
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I was around 11.5:1 on my 03' and I was able to run fine on 87* but it had no power due to having to have the timing set so low.

But it ran fine on 93* with more timing.
DCR is where it's at, that helps more than SCR.
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Old Dec 14, 2007 | 06:54 PM
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Yeah think about it, my stock vette has 10.9 from the factory. It would run fine on 91.
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Old Dec 14, 2007 | 08:41 PM
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anybody know what the stock dcr is for 5.3 or 6.0?
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Old Dec 14, 2007 | 08:50 PM
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you can use this to help figure up you dcr if your running a comp cam. https://ls1tech.com/forums/showthread.php?t=630637 from what i have read over and over is 8.7-8.8dcr for 93 octane.
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Old Dec 14, 2007 | 09:01 PM
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Does anyone know how much the deck height, and what cc is the dish of a stock LQ4?

I'm trying to figure out my comp. ratio
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Old Dec 14, 2007 | 09:35 PM
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i think its like .006 out of the hole but not sure on the dish.
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