I would also agree with you that the 9.77 should have been fine with the HC-02. But there are a couple wild cards there. The 8VR replacement pistons are really hard to predict. Sometimes they have a terrible quench and can be .040 down in the deck. Then I think either the crown of the piston runs hot between the inner and outer valve reliefs and/or the extra contours create hot spots and end gas issues. Some engines will do ok with those pistons with good compression, most seem to be with OEM pistons that had a decent quench and a OEM cam. The replacement ones with the shorter height seem to have all kinds of problems unless the deck is cut like your engine.
Another thing that might have worked against it was the cam being retarded that much. Whenever I degree a cam in I assume it is running 2 degrees retarded from were it is set at. So 4 retarded is getting closer to 6 dynamically. That is not a big deal on a little cam with a small amount of overlap. But I think the bigger cams start heating up the air charge significantly when they are ran retarded. IMO, that is one of the reasons that bigger cams loose performance faster when timing chains stretch. But your timing chain could have easily stretched those 4 degrees to if you drove it much, it could have started out dead on. I would still tend to believe it was more to do with the 8vr pistons.
I am all for more compression, a good piston, rods and the summit 2801 or 2802. I have never ran the HC-02, but always though it looked like a great performance street cam, unusual to see issues with it. Jay
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