i am pulling the heads off of my 555 bbc and inspected the solid roller lifters. i noticed one pair came out slightly hard, had to work them out. then i noticed that there is scuffing on the side towards the cylinders. they all have it but all of the others moved nicely. all of the rollers were fine and the cam looks fine. didn't feel any scoring on the lifter bores either but will have to look a little deeper tomorrow. dart big m block, anyone seen anything like this? has about 800 street miles on it, hasn't been to the track yet. thanks in advance, paul c.