BigT500W

So I bought a complete fresh rebuilt 355 olds this summer. Wanted to upgrade the cam so, I did a cam swap on my Oldsmobile 355, about 6000 miles ago. Brand new comp 206/212 cam with comp lifters to match. So fast forward after stabbing the cam and putting the engine back together, a couple of my lifters are ticking away. I was told give it a while they may stop after the springs wear in. Here I am 6k miles later and still ticking.

I have all new lifters, rocker pivots/perches, pushrods. Some folks have suggested that I need an adjustable valve train because the engine has been rebuilt. I am wondering wether that is the case or do I just have faulty lifters causing the ticking. My question is how do I rule out having slop in my valve train and needing an adjustable rocker set, so I can be sure my lifters are faulty before I change them.

Whatever it is I want to go ahead and buy it. But I need to know am I buying a set of lifter or adjustable rockers.

oldcutlass

You need to make sure you have the proper lifter preload, .020-.060".

442Harv

Find the ticking lifters. Take valve cover of. Run the motor, and slip a small feeler gauge under rocker and valve, and if noise go away you know that the bad valve area, not right preload, worn rocker, or wore pivot.If it don't go away, probably bad lifter?

Greg Rogers

Yeah it all about base circle. If new cam base circle is smaller then you need that much longer pushrods.

cjsdad

The unscientific way to find out if you have any lifter preload, take the valve covers off and try wiggling the pushrods on the closed valves. If you get a lot of wiggle/rattle or can move the pushrods up and down, your valve train is out of adjustment. Because there isn't any. If the base circle of your new cam is smaller than the factory cam, you will need adjustable rockers or custom length pushrods. Make sure your cam is still good. If it didn't break in properly and is wearing away could also cause ticking lifters in an Olds engine.