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CMI valve cover clearance issue

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CMI valve cover clearance issue

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Old 08-06-2012, 06:50 PM
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Default CMI valve cover clearance issue

I am finishing up a build and have run into an issue with the exhaust. I am running stud girdles and have a taller valve cover to house them and when I went to bolt on the exhaust it hits the valve covers. The heads are 990's and the ports are on the low side but I am at the end of my rope. I thought about a spacer on the exhaust or a double flange but the stud kit stands a bit too tall and therefore won't clear. A standard flange will work if I can find the correct bends and clearance. Also I need to get to my valve train to make the adjustments so I hope someone can help me figure out what to do.
TIA
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Old 08-06-2012, 06:53 PM
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Hi performance marine valve covers will clear girdles and the exhaust, they are angled on the edge where you are hitting at so that they clear.
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Old 08-06-2012, 06:58 PM
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Cp performance or do you run something different?
Recomendation?

and thanks!

The pair I have were dented to clear the low valve covers and I wounder if I should send them out to be fixed. It is not smashed but they are wet and I cant imagine that would be a good situation.
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Old 08-06-2012, 08:59 PM
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My Eickert 2-piece covers with extra-tall lowers to clear girdles would hit E-tops without spacers even on Dart Pro-1 heads with 0.300 high exhaust ports. I run 3/8" spacers. Makes for a big package on tall-deck motors. Motors were put on 36" centers as I have drivelines.

The clearance is tight, but I can remove a valve cover (this is where the two piece pays off) without pulling a header.

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Old 08-06-2012, 09:05 PM
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The factory 500 efi covers clear the girdles just fine, Potter put girdles on mine when he made it into a 540 for me.
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