I made some quick models of a standard intake valve to model different angle back cuts just to see what looks most promising.
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| Standard Valve Shape |
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| 30deg backcut |
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| 30deg back cut |
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| 20deg back cut, to flat of a shape imho |
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| 30 & 20deg back cuts |
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| 30 & 20deg back cut, most promising |
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| 30 & 20deg back cut |
