How long will it take to convince some folks that flat tappet cams must be “broken in” and operated over the long term with enough zinc phosphate (ZDDP) in the oiling system?
Professional engine builders should all know by now that the major oil companies have greatly reduced the amount of high-pressure ZDDP from their oils (primarily because late-model engines mostly feature roller cams that don’t need this mix).
It should be common knowledge, by now, that any flat tappet cam MUST be seated by using either a dedicated break-in oil (re Brad Penn, Joe Gibbs, Royal Purple, etc.) or by using the oil of their choice PLUS a bottle of ZDDP additive (Comp Cams, Royal Purple, etc., with more companies offering this additive as time goes by).
However, in order to expect a flat tappet cam to live over the long haul, a sufficient amount of ZDDP must also be used at every oil change (again, by using either a specialty oil that already contains ZDDP, or by adding ZDDP concentrate to the oil of choice).
Some folks just won’t listen.
I’m referring to the average muscle car/performance car owner.
As a case in point, a buddy of mine recently bought a 1972 Yenko Nova clone equipped with a 454 Chevy mill, fitted with a flat tappet cam.
According to the seller, the engine had about 2500 miles of use at the time of the sale.
Shortly after buying the car, the cam went south, in a big way. All lobes were ground down, with six of the lobes missing a whopping 0.078″ of meat at the ramps and peaks.
As you might expect, all of this casting swarf travelled throughout the engine, roaching all bearings (including a total wipeout of the thrust bearing).
My buddy brought the car to my shop, we pulled the engine, tore it down to a bare block and started over (align hone, cylinder hone, replace the crank, replace the oil pump, replace rings, seals, gaskets, pushrods, cam, lifters, etc. You get the drift.
As it turns out, the previous owner (who originally commisioned the engine rebuild) never added any ZDDP.
As a result, my friend was forced to plunk down another $3000 or so in order to remedy the situtation.
I’ll assume that our professional engine builder readers are already painfully aware of the need to provide the proper high-pressure lubricant for any flat tappet cam setup.
However, it’s quite apparent that the muscle car restorers, drivers and collectors still don’t grasp the critical apsect of protecting their flat tappet cams.
We need to inform and remind customers of the absolute NEED to protect their cams by using the proper oil/ZDDP additive…not only for initial break-in, but over the life of the engine…at EVERY oil change.
Today’s mainstream engine oils DO NOT contain the high pressure lubrication required by flat tappet cams.
Luckily, companies like Joe Gibbs, Brad Penn, Royal Purple, Comp Cams and others have dug deep and have developed the necessary oils and additives.
It’s out there…but we can’t put a gun to the car owners’ heads to purchase and use the stuff.
Just remember to make them aware, and if that means screaming at them and threatening them with a smack in the face, then so be it.
It’s no fun when a skilled engine builder produces an excellent final product, only to have it ruined by the owner who doesn’t listen to sound advice.