I have to disagree some here. IMO and IME 100 lb or 125 lb springs are ~ no issue on a flat tappet cam. In fact the stiffer spring might even help encourage the lifter to rotate. FWIW I had 125 lb springs in my 3.8 S1 on a solid stick and it came out so nice after a few years of running that it is like new. Taper still fully there on all lobes, etc.
The cam may have been ground incorrectly. I have personally seen at least 3 flat tappet sticks lately that were tapered wrong- wrong order/direction. One thing you can do is check the lobe taper direction on your remaining lobes. If any are the wrong direction you could at least say that the cam was tapered incorrectly. If they are right, then maybe no conclusion can be made on #3 since the evidence is now wiped out. Or, you may have enough left on the base circle area to see the taper direction; Dunno. The #3 exh lobe is the odd lobe out of the 12 on a Buick v6, so chances are there that it could have been tapered incorrectly.
There were some cam blanks that we found that had the #3 exh lobe positioned wrong. In fact Comp supposedly purged their stock of bad blanks after we talked about this several years ago.
The block may have the #3 exh lifter bore in not quite the right spot. One way to tell I guess is to put in a known good cam and eyeball it; then put in the dead cam and compare.
Unfortunately the rollers on the v6 can have issues too. I don't think we have a 100% guaranteed fail proof setup yet. We pulled a hyd roller out of a friends car recently that had all the lobes ground into, as if the rollers had slid vs rolling.
Bottom line, whenever putting in a flattappet cam, you must check all 12 lobes and holes very carefully to begin with. This has been repeated many times on here...
TurboTR
