I'm considering a high lift, long duration hydraulic roller cam for my A-engine. It's a 323 that still has the factory roller lifters with about 50,000 miles. My question is, is it essential to replace them when installing a large cam to ensure proper break-in? (Will the factory lifters damage the new cam lobes?)
If the rollers are in good shape, you can reuse them. That said, I don't know what you mean by high lift-if this is a very large cam, you should consider aftermarket lifters and will obviously need better springs.
We have a 318 poly with bent push rods. There is no apparent cause. Cam and lifters seem ok. The engine ran with one cal. missing. When we checked compression with no spark and plugs out, 4 more lifters were bent into severe s shapes. We have not opened to see timing chain, and have not yet pulled a head, but does anyone know of this with the poly engines?