The last 4 Pontiac engines I have been involved with at the school or personal use have been flat tappet solid, (2) and flat tappet hydraulic (2). Flat tappet hydraulics were set up at 135-140 closed and 290-300 open. Flat tappet solids, 145-150 closed, 320-330 open. I think the oil used doesn't really matter as long as non-synthetic for ring break-in. I used what I had easy access to. 2 of them Amsoil break-in oil, 1, VR1, 1 Joe Gibbs break-in oil. Used a product called Cam Shield on the lifter bottoms and cam lobes. Broke-in with outer spring only on all of them for 1/2 hour from 0-30% load variable on the dyno. No issues.
In the last 20-22 years at my school, we have had 4 cam and/or lifter failures on the dyno. This is out of 12-16 engines a year. So that's about 300 engines give or take. No Pontiac failures. The 2 flat tappet failures were both small block Fords. One was a puny, restoration style rebuild on a 260 Cu In. with stock parts. 105 lbs on the seat and barely 200 lbs. open Took 3-4 cam lobes off in 1/2 hour break in. Engine started to miss and we found it quickly. He went back with a roller cam. The other one was a 347 Ford stroker. It lasted through break-in and 3-4 dyno pulls. Took a couple lobes off. The roller cam failures were 1 small block Chevy and 1 big block Chevy. The small block had a tie bar break-off during break-in and it turned and killed the cam and damaged the lifter bore. We had to sleeve it. Plus other damage. The big block had one hydraulic roller lifter that would never pump up. Big, noisy ticker. We tried everything we could to make it work, no luck. It was a Morel lifter and made in such a way it could not be disassembled once the tie bar was riveted in place. Didn't do any damage but we never figured out what the cause was. They sent a new pair and it did fine. So I don't think the number of failures are as high as it seems in the internet. But a failure CAN be quite traumatic, expensive and time consuming to fix.
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