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ET 215's. Help calculating my compression?

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Old Feb 14, 2006 | 07:42 PM
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Default ET 215's. Help calculating my compression?

Hey guys, need some help. There have been no mill to the heads yet. I have .075 out of the hole using .045 cometics. I verified my clearance and I have alot on the intake and about .192 on the exhaust. What would my current CR be? If needed, how much could I mill and be safe without fly cutting. The cam is a monster and I can't believe I have this much clearance available. Thanks in advance!
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Old Feb 14, 2006 | 07:50 PM
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Joe G, where you at?
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Old Feb 14, 2006 | 08:33 PM
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Originally Posted by ceo2858
Hey guys, need some help. There have been no mill to the heads yet. I have .075 out of the hole using .045 cometics. I verified my clearance and I have alot on the intake and about .192 on the exhaust. What would my current CR be? If needed, how much could I mill and be safe without fly cutting. The cam is a monster and I can't believe I have this much clearance available. Thanks in advance!
Hi,

First did you really mean .0075" out of the hole with what pistons? Stock or aftermarket. If aftermarket what CC reliefs do they have?
What size combustion chambers did you get?

Phil
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Old Feb 14, 2006 | 08:50 PM
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They are stock bore forged flat tops. And yes, .0075 out of the hole. My bad!
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Old Feb 14, 2006 | 09:09 PM
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what cc are the heads currently? a 346 right?
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Old Feb 14, 2006 | 10:37 PM
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yes, 347 and heads are 62cc.
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Old Feb 14, 2006 | 11:13 PM
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I get 11.21. Someone should verify.
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Old Feb 14, 2006 | 11:28 PM
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Originally Posted by 97 SC Cobra
I get 11.21. Someone should verify.
ya i got 11.17:1
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Old Feb 14, 2006 | 11:28 PM
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how big is the cam and whats the lsa? you can probably get away with more static compression
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Old Feb 14, 2006 | 11:40 PM
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What about using a 0.040 cometic and not milling the heads? Doesn't milling reduce the flow slightly?
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Old Feb 15, 2006 | 08:43 AM
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Originally Posted by ceo2858
Joe G, where you at?
Joe G, or me

Steve, I didn't know you were doing a forged bottom end also
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Old Feb 15, 2006 | 09:05 AM
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Hey Joey, Yes YOU! And yes, I decided what the heck, it was a piece of cake to pull the motor with everything off so I just popped in some forged stuff.
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Old Feb 15, 2006 | 10:04 AM
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Is there anyone from ETP on the forum to answer this? I really like the heads, but I also really like the support/response from guys like Tony Mamo at AFR. Might be the difference between which set of heads I eventually buy.

Keep us up to date on what you find out!
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Old Feb 15, 2006 | 10:08 AM
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Originally Posted by IFLUBYU
Is there anyone from ETP on the forum to answer this? I really like the heads, but I also really like the support/response from guys like Tony Mamo at AFR. Might be the difference between which set of heads I eventually buy.

Keep us up to date on what you find out!
They are quite active on the other site as they are a supporting sponsor there. PM me if you don't know what I'm talking about. They are very quick to respond to any questions I have.
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Old Feb 16, 2006 | 04:26 PM
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Originally Posted by 97 SC Cobra
They are quite active on the other site as they are a supporting sponsor there. PM me if you don't know what I'm talking about. They are very quick to respond to any questions I have.
Thanks, that's good to know. I don't go over to the other site as much as I should, but at least I know they are there!
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Old Feb 16, 2006 | 05:44 PM
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Hey guys, good luck with getting them to answer your requests or emails. I have sent both PM's and emails and none of them get answered. You would think they would be more than happy to assist one of their customers but hey, guess NOT!
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Old Feb 16, 2006 | 10:44 PM
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Call em.
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