Have you verified proper cam lift on that lobe?? That sounds like a flattened lobe which is highly unusual with roller lifters. Did you see any sign of distress on the lifter you removed?
Could it be a wrist pin or rod bearing on #7 instead?
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Frank W
90 5.0 LX coupe Stone stock soon to be daily driver
74 Chevy Laguna Type S-3 305 apart in garage, getting a 454 to put next to it
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