ZDDP (or lack there of)
Hey all!
I know this is off topic so I hope I'm asking in the right area of the forum...
We just finished (less than 6 months ago) a rebuild on my 302 in the 67 Mustang... it had less than 40 miles on it when it chewed up the cam. We took the precautions to break in the Comp Cam correctly (keep the RPMs near 2k~2.3k, let the block get warm to properly seat the valves etc) and then we noticed what sounded like lifter noise. So we removed the valve cover and noticed that the exhaust rocker on the #4 cylinder was loose during part of the cycle (we manually turned the crank). The rocker was properly torqued and the lifters were new with the cam... rod was ok and the valve spring was also in good condition (didn't break, which is the second thing we checked after the rocker).
After a week of discussion with a number of the "old hot rodders" (that's what the more senior members of my car club call themselves lol) and the mechanic (he has around 40 years of engine builds under his belt and this is a new one to him as well) the best, yet least logical reason is that the lack of ZDDP caused premature cam wear thus causing the 1 tappet (and 4 others to start) to flatten/round off completely. None of us were aware of the massive federal mandated change in the formulation in the more conventional oils, let alone the need to actively add ZDDP additives to the oils (they are from the old school train of thinking where you do not need to add stuff to the fuel, oils etc unless it is proven necessary through experience or research).
I guess what I'm curious is if anyone here knows of, or has had something like this happen to them. I bought the Muskrat to learn as much as possible about automotives starting with the more traditional yet semi easy to work on (few things cannot be taught better than by hands on, IMHO), and it's in part why I bought the crossfire, something modern to work on while I continue work on the muskrat.
Thanks in advanced... I'll get some photos up when I can, there is a good one of the chewed up lifter sitting next to a good one.
-Tim