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Compression ???

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Old 05-18-2017, 02:17 PM
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Default Compression ???

I am planning on doing some work on my G8. I am looking to bump compression up some looking ti mill the heads, any advice what would be best 0.030 or 0.040? And can you recommend me the proper head gasket?
Old 05-18-2017, 05:46 PM
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What compression ratio you looking for?
Old 05-18-2017, 06:41 PM
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Honestly not totally sure, was thinking 11.1 just want a bump for extra power when I get rid of DoD and swap cam
Old 05-18-2017, 07:25 PM
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Call BTR or TSP. Best to stay under 11:5 for timing purposes.
Old 05-18-2017, 07:59 PM
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L76 has 10.4 has 10.7. Those are both pretty good. Id mill no more than .020 and use a stock head gasket or .045 at thinnest. Every .006 is 1cc. Youlm run into ptv issues with a med cam more than that on a stock head gasket.
Old 05-19-2017, 02:46 AM
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Default Felpro 1041

Hi the (your ?) G-8 was first made in 2008 though "down under" I am not sure that a 58x TW is fitted.
(Gray Sensor)
The UPGRADE from the 24xe TW to the 58x TW = .5 C.R. increase in the Knock Rating.

My HG choice is the Felpro 1041 which will help the Squish, good for Knock Rating.

Thus the HG -.010" AND the "mill" of -.020" = -.030" OK
YES do the DOD REMOVAL
The L/C of the Camshaft is VERY critical to PV, I would use a 116 C/L.

I can "model" PV with EAP AND I do not require a fee.

Lance
Old 05-19-2017, 02:51 AM
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Using a thinner head gasket on an unknown piston to deck clearance isnt good, and milling the head and using a thinner gasket severely limits your cam options. Youve got a good enough cr as it is.

Get a mid range 227/235 cam and have some fun with it. Our dod delete kits are literally the least expensive of all the places and the most complete.

Shoot me an email if you want more info. and with your gearing id stay away from a narrow lsa, but going too wide will make you run the rpms up to make power.
Old 05-19-2017, 03:00 PM
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Well maybe not so worth the milling of heads
Old 05-20-2017, 03:07 PM
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I have a early 2009 G8. I milled my heads .024" and used a .040" cometic gasket. My CR is 11.45:1 Also, i liquid volumed my cylinder heads and they came out to be 64.3cc with Ferrea L92 hollow stem intake valves and stock exhaust valves. PTV clearance will vary depending on what cam you run.
Old 05-20-2017, 06:36 PM
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With a .040 gasket and alum block id hope your ptd clearance is .005 or less.
Old 05-20-2017, 06:47 PM
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Piston to deck was .004 - .006 above the deck. Checked with a deck bridge and a dial indicator. .034 / .035 quench.
Old 05-23-2017, 09:04 PM
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With my 06 GTO with the LS3 heads, I had them milled .030" and used .040" gaskets. Running a CamMotion cam 230/238 .626" 113+3 and had to flycut .050". Compression cam to 11.27:1. Just had the car on the dyno last month, it pulled 480/434. Also I'm running a RCR modified intake.



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