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?'s about lowering compression

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Old Aug 8, 2005 | 08:34 AM
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Default ?'s about lowering compression

I want to lower the compression a little on my 01 ws6 (bolt ons lid,headers) to run my phamspeed turbo kit I got. would It better to to install comtec head gaskets or 6.0 liter heads? I'm hoping to get compression anywhere from 8.5:1- 9.5:1 any suggestions would be very helpful
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Old Aug 8, 2005 | 06:35 PM
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If you get stock 317 casting 6.0 heads and the GM MLS gasket it will lower the CR to 9.2-9.5 area. To go lower then that ya have to use different pistons to get the desired CR. GL man.



John
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Old Aug 9, 2005 | 05:57 AM
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depending on the chamber size (if it was milled down or not) it will be 9.8-9.5:1
you can use a thicker gasket like a .067 that will get you down to about 9.2 with the heads.
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Old Aug 9, 2005 | 09:58 AM
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6.0 heads might net a half drop in compression.

I wonder if any of the aftermarket castings can be purchased with 74-76cc combustion chambers.
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Old Aug 9, 2005 | 03:59 PM
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I just picked up a set of stock 6.0 heads from my buddy at a smokin deal.would it be okay to run 918 springs and 1.8 rockers

Last edited by Dr.x; Aug 9, 2005 at 05:38 PM.
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Old Aug 9, 2005 | 04:37 PM
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Originally Posted by Dr.x
I just picked up a set of stock 6.0 heads from my buddy at a smokin deal.would it be okay to run 918 springs and 1.8 springs?
I'm going to put 918's and hardened pushrod's on there while I got them off the car...

josh
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Old Aug 9, 2005 | 10:39 PM
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Jonathan, I just picked up some 317s too. Where do I get the .067 gaskets you mentioned?

Wanna come over and help me swap them out?
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Old Aug 10, 2005 | 05:36 AM
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Originally Posted by DarkFormula
Jonathan, I just picked up some 317s too. Where do I get the .067 gaskets you mentioned?

Wanna come over and help me swap them out?
cometic
800-752-9850

if you come over here and help me get my car running first
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Old Aug 10, 2005 | 05:43 PM
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If you give me an advanced date, I can come over and give a hand.

BTW, those coil packs in your sig. They are the one-piece bracket, will they work on my car being a '98?
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Old Aug 10, 2005 | 08:16 PM
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I run 6.0 GM MLS head gaskets.
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Old Aug 10, 2005 | 08:28 PM
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John, got a PN#? Are these comparible to the cometics Jonathan was referring to?
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Old Aug 11, 2005 | 06:54 AM
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Originally Posted by DarkFormula
If you give me an advanced date, I can come over and give a hand.

BTW, those coil packs in your sig. They are the one-piece bracket, will they work on my car being a '98?
the coil pack and brackets are for a 99+, i think the coil packs will work, but definatly not the brackets as your brackets are somewhat cast into the head

the GM 6.0 MLS gasket is pretty much the same constructionto the cometic (lest i think) but with the cometic you have different thickness where as the GM one you do dont.
if you dont need a certain thickness get the GM one as its cheaper and some say it seals better

going to try and work on my car about every day in hopes of getting it done before the TA nats (but history shows i almost never get it done.)
I got to put my tranny back in (need to get my clutch back first), install my master, bolt on my accesories and radiator, bolt up my turbokit, mount my IC 9which needs to here here) order and make my IC piping then put on my bumper and fender.
almost any date is good
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