[Bill S]

In another thread early this summer I posted about discovering two worn lifters, but in frustration just put the car in my back garage bay and covered it until I had time over the holiday to pull the engine and tear it down.

Engine is 1970 455 four bolt main, stock crank 0.010" under, ICON forged pistons 0.040" over, Maxx lite connecting rods, Mellings 041 cam, Rhoads VMax lifters with vertical oil groove, Harland Sharpe 1.65 roller rockers, headers, Cliff Ruggles 800 cfm Qjet, ported '67 stock intake, 6X-8 heads ported per Jim Hands book, SI SS valve with 1.77 exhaust, and 995-16 valve springs at 1.700" height. Compression is 9.4. Did this engine in 2011 for my '67 Firebird, driving it only in the summer not many miles. Over the years I thought it was not as powerful, but this summer it developed a severe miss, so I pulled the valve covers and found two loose rockers. Pulled the intake and yup two worn lifters.

So that I had time over the holiday, I pulled the engine and did a full tear down. The two lifters are worn about 0.170" and the cam lobes about 0.100". The only good thing is I used two Filter Mags on a Baldwin B39 filter and a magnetic drain plug. Cut open the filter and yup metal in there. Upon complete teardown I don't see more metal and the bearing don't look bad, minor scratches but the crank journals look good. I plan to send the block out for cleaning and will install new bearings and a oil pump.

So, why this wear ?
I did everything per sage advice. Correct lube on the cam, break in with no inner springs, oil with zinc, lifters with the Superlube groove. I believed I would never have to open up this engine again, and enjoy this car for the next 30 some odd years, as a cruiser. (Owned the 'bird since 1980)

Any root cause suggestions ?

All lifters rotate, valves move freely, had a reputable shop do the heads and verified the spring pressure / height. I adjusted the preload correctly, triple checked it.

I see in other threads there seems to be two camps; nothing wrong with HFT cams, or go roller. I am willing to spend the money for reliability.
What the latest story with retrofit roller lifters reliability ?