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#15 heads

  1. Engine Discussions
    I'm running a 1970 YH 455 block with number 15 heads with a Comp Cams 276ah - 10 cam. Comp Cams recommend using 995 - 16 valve springs which requires Machining of the valve seats on the heads to achieve the proper spring installed height. The Machine Shop is telling me that there's not enough...
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