[wrogers55]

I'm replacing a CompCam cam and hydraulic roller lifters in a SB 418. Previous posts here showed I found what might have been a soft lobe (maybe not too) during an inspection of the motor and Comp replaced the cam but thought it really wasn't necessary and I decided to replace the lifters as well. A little background, the motor was built with all top shelf parts, triple springs on AFR 205s, extreme duration and lift, FI, street use only and was an absolute monster, probably near 575 HP. I bought it in the car with a couple thousand miles on it, so I'm getting to know the internals as I go.

Now, the mystery is there is a huge difference in the internal spring pressure of the original lifters and the new Comp lifters. I mean huge. The old lifters can hardly be budged when you put pressure where the pushrod goes. It will move, but it takes all my weight to make it move a few thousands. The new lifters are actually pretty easy to push down a bit with one hand. The old ones actually feel like they are solid, but I can feel a very slight movement when I put just about all my weight on top of it.

Another interesting thing is the motor was set up with zero valve lash, no preload at all, just flat zero all the way around.

I have it limited to 6,250 and never once had a float or tick issue. Ran great.

So, what' the deal? Is this some kind of "trick" lifter acting like an almost solid roller? This is a new one for me but I have found some interesting stuff in this motor along the way.

I'm also wondering if this is what might have beat the cam up as well.

I really want to just put in the new lifters from Comp, degree the thing up and be on my way.

Any ideas will be greatly appreciated.

Pictures are easy if necessary.