To zinc, or not to zinc; that is the question

[GTRS Fiero]

Does zinc additive in the oil really help the cam?

[Raydar]

It depends upon who you ask.
Anecdotal evidence says it does. Or at least doesn't hurt.
OTOH, there was at least one study done that said that there are other factors that are more important. (The general "feeling" of that study being "you get what you pay for".) I'm at least a bit skeptical. Of course it's in the oil companies' interest to promote the expensive stuff. But I'm not cynical.

When I built my 3.4, a few years ago, I installed a Crane 272 cam. Around that time, Crane cams in general, and the 272 in particular, were supposed to be wiping lobes and lifters on a regular basis. I used zinc assembly lube, zinc break-in additives (I think) and Rotella T (zinc-rich) oil.
Ten years later, the engine is still running (having gone through several owners) and having other issues (marginal oil pressure, and a broken valve spring, among others) but the cam is apparently still good.

As always, YMMV.

[GTRS Fiero]

There were BIG arguments on this on PFF.  They got into ZDDP and lots of stuff.

I don't have a 272 cam, nor a Crane cam.

[Raydar]

For a well broken-in stock cam, I would imagine lots of people just use regular oil. Castrol seems to be a favorite, but others are good, too. I stay away from Pennzoil and Quaker State, due to old-wives tales regarding paraffin based oils. (Which may not even hold true any more, but then it is my choice.   Don't want to start any arguments here. Use whatever works for you.)

[GTRS Fiero]

Valvoline does the paraffin thing, too, and recycles used oil into new oil.

How about Mobil 1?

[Fierofool]

I've been using Rotella T 15 w 40 diesel oil in both my V6's.  The 3.4 has about 30K on a new crank kit and cam bearings.  I think the engine had less than 100k on it when I bought it.  It's still on the same lifters and cam and heads.  Untouched. 

ZDDP is an addative that includes zinc in it's formulation.  It can be bought separately and added to your regular oil. 

My regular oil preference is the Castrol brand.  I've been running it in all my cars since 1988.  Only had 1 engine failure and that was after I let someone drive it in the mountains.  I later found that their driving habits pushed the engine to the redline when accelerating, and when gearing down.  That engine had about 135,000 on it with Castrol. 

The reason for choosing Castrol is because I've seen the inside of one of my engines when it had 280,000 + miles on it.  It was nice and clean with no gunky buildup on the springs or rocker arms.