Zinc in Oil

[Changin Gears]

Just wondering, who has had a camshaft failure that they think was caused by lack of Zinc/ZDDP in their oil?

[73Chally]

Everything I have read says that you only need it if you run an aggressive cam, but if it is pretty much a stock grind, then there is no need for it.

[Moparal]

In all my years of hp engines and engine building, I have had 1 cam go bad in my stuff and repaired a few for friends.  But it has been a while.  Gary, I never suspected lack of ZDDP , I always figured it was soft metal like a bad core, or a bad lifter.   Or for that matter, lack of oil protection due to somthing else. 

[70_Hemi_Cuda]

I ran MOA Zinc Additive in my built 340 and even 3 years later the cam and everything still looked brand new. My engine Builder Tom @ R&S Racing in Albert Lea built my motor and told me I should use it. Tom won the Mopar Engine Builder Challenge several years back so I tend to follow what he says lol.

Engine specs on my old 340:
.040 Speedpro Powerforged pistions 10.33 to 1
Edelbrock Aluminum Heads
Double valve springs
Comp Cams Extreme Energy 284 Int 296 exh w/.510 lift
Crane Gold Race Aluminum roller tipped rockers
Forged Crank/Connecting Rods
Balanced and Blue printed

[Strawdawg]

Everything I have read says that you only need it if you run an aggressive cam, but if it is pretty much a stock grind, then there is no need for it.

All flat tappet cams need it.  The more aggressive the spring rate, the more you need. 

One of the major contributors to the problem have been the imported soft lifters.    Many seem to ignore that part of the articles that have been printed.

The last Mopar Action had a good article on the subject.  The most impartial articles/write ups seem to come from those that are not selling oils, or additives, in my opinion

For sure, there is a lot of really contradictory statements on the net on the subject but a lot of reading helps

[Chryco Psycho]

As an engine builder this is really the only failure we have had , probably lost 5 cams in the last 4 years , never had a problem before 4 years ago , I have to believe it has something to do with oil , even our cam suppliers have never seen this level of failures

[73Chally]

Never had a problem in 20 plus years of owning these cars, but none of our engines have been anything beyond basically stock rebuilds.  Could be the quality of oil, and could also be the quality of the cams.  I have also never used hardened seats, again with no problems, but most people you ask say they have to be used, too.  I'll take real life experience to what most people write.  It does seem like a lot of the articles are meant more to push sales and provide that "scare tactic".  I don't know, maybe I've just been lucky.

[tactransman]

I had one go bad in a 440 with a .672 lift. It was only one lobe though so it makes me wonder if they missed that one when they hardened at the factory. (It was a Lunati about 5 years ago)

[Chryco Psycho]

16 of the last 20 years the oils were adequate to keep the cams alive , with the new SM rating this is no longer the case , 2 years ago we had 1 360 fail multiple lobes on 2 cams during the break in 20 min run

[femtnmax]

Over the last few years I have replaced several cams in big block farm trucks (fords and dodges) due to cam lobe/lifter failure.  Two of these were new cams that failed within 1000 miles.  Another cam actually snapped in half after wearing down many of the lobes with about 5000 miles use.  I was wondering WTF was going on, then read about the changes to todays engine oils.  Crane cams never said anything about it when you bought one of their cams...then I found a notice included with a comp cam discussing cam failure and the changes in todays oils.   None of these problem engines had the extra zinc in the oil which they now recommend.
You can feel the difference between the older style oil and todays EPA crap.  The older oils had a true "body" to them, with oil on your fingertips no matter how hard you pressed your fingers together the contact was slipperly smooth.  The newer oils don't pass this simple comparison.   Over the years I had noticed that todays oils did not feel the same as 30 years ago, but thought I was just forgetting details...no the oils are different.
I would not be surprised the lack of quality manufacturing is part of the problem, but I would not assemble and run a flat tappet cam engine today without it.  Whether to continue to use the zinc rich oil after breakin seams to be another debate.  I do because of the more aggressive cam lobe profiles.

[70_Hemi_Cuda]

I cant speak for anyone but myself and I had great luck with the MOA Zinc additive and ZR1 racing oil. Like I said earlier my cam looked brand new still after 7k miles on it

[UKcuda]

I don't know if it's the same stuff you can get over there, but on my three USA V8 flat tappet cars I use a 15/40 that's specced for turbo diesel engines as well as petrol engines.  I buy it in a 25 litre drum and that way it works out quite reasonable on price.

Because it has to meet diesel spec it has higher wear additives (probably ZDDP but could be something else or a mix?).  Anyway, I've been using it the last seven years or so and never had a problem.

I don't know about break in oil additives (apart from the molibdenum poly.. stuff you wipe on the fresh cam, which is essential) but if you can make it through the first 500 miles with a good break in then the oil spec. becomes less important.  So I guess using a break in oil additive is not a bad gamble - you only use it once.  But on a moderate cam I probably wouldn't bother.