INTERNAL ENGINE MODIFICATIONS Valvetrain |Heads | Strokers | Design | Assembly

Dynamic Compression

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Old Jul 10, 2009 | 09:38 AM
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Default Dynamic Compression

Anyone know the stock DYNAMIC compression of a 05 LQ4?

What will it change to with a 210/218 ish cam?

how much static will i need to increase to get it back to the same?
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Old Jul 10, 2009 | 03:20 PM
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If I recall, there were a couple fellas on here pretty savvy with the whole dynamic compression calculations. I'm sure its not hard to do, I just don't have the page or formulas handy. Hopefully they'll chime in here.
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Old Jul 11, 2009 | 02:46 AM
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Here's the first one that came up by typing "dyanamic compression ratio calculator" into google: http://www.wallaceracing.com/dynamic-cr.php

this is the second link on that page: http://www.empirenet.com/pkelley2/DynamicCR.html

Here's the google page: http://www.google.com/search?hl=en&q...rlz=1R2ADBR_en

Don't know the stock DCR, but I'm guessing somewhere between 7.5:1 to 8.5:1?
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Old Jul 11, 2009 | 10:43 PM
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i don't know when the intake valve closes or else i would have calced it myself...
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Old Feb 12, 2010 | 12:38 PM
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Bump!
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Old Feb 12, 2010 | 01:44 PM
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The dcr on a stock lq4 is down in the *******. Its probably about 6:1. That cam would probably raise it up to the mid to high 7s
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Old Feb 12, 2010 | 01:48 PM
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what are the stock cam spec of a lq4? ???/??? .???/.??? ???+? and what is the stock CR of the LQ4. knowing that i can come up with the approximate DCR.
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Old Feb 12, 2010 | 02:41 PM
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196/207 .467/.479 116 lsa
9.4:1
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Old Feb 12, 2010 | 02:46 PM
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is it a +1, +2, +3, +4, etc...
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Old Feb 12, 2010 | 02:59 PM
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everything I can find just says 116
Year Platform Part Number Valve Lift in/ex -in Duration in/ex LSA Timing on Cam CL

2001 LQ4 Truck/SUV 12561721 .479/.467 196/207 116 117/115
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