On the cam situation: The springs check out ok to handle the added lift, but at .690, they are at 425 lbs.. The "pits on the lobes are all, while close to the nose, on backside ramp.
You kind of need that much spring pressure to maintain control of the valvetrain at high rpm's with that type of cam.
How do the bottoms of the lifters look?
Does it appear that little pieces of the cam have just fractured/broken away?
If you're going to swap out the cam, I'd suggest something smoother with a little less lift.
A little less power sure, but you should be able to juice it back up again.
Have you pulled the thrust bearing out yet? The hopes would be that if the high-ish thrust clearance is the result of wear, that the bearing took the brunt of it and that the crank thrust surface is still good.
68 Satellite, 383 with stock 906’s, 3550lbs, 11.18@123 Dealer for Comp Cams/Indy Heads
