Basically the story goes with the advent of catalytic converters. I'd say everyone who's 30 older older will remember that catalytic converters didn't last very long in the past.
You bought a new car and 3 years later you had to replace it. For this it has been demanded of car manufactures that the live of catalytic converters had to be at least a certain time.
here the details:
[quote zddplus.com] The EPA's program called for 100,000-mile catalytic converter life by 2004, 120,000 miles by 2007, and 150,000 miles by 2009.
What made those catalytic converters die was an additive in engine oils (zinc and phosphor) that is needed at high pressure contacts. So slowly but surely those were removed from the oil.
The side-effect that caused was that flat tappet engines, which are not produced for tyhat reason anymore are wearing their cams and lifters.
Once the hardened lobe of camshaft is worn (only 0.002") the rest of the lobe will eat away completely, which can either cause catastrophic failure (shrapnel in engine oil), or just the fact that this cylinder is not opening one or all valves anymore.
This topic is wildly discussed in classic forums. Some seem to believe in it, some don't. But as the oil companies seem to agree on this I believe in that story.
What can we do?
Basically buy engine oil that contains high zinc/phosphor or ZDDP or additives.
I do not know if it's possible to source additives like that in Ireland but a crude workaround seems to be to just use Engine oil that is specified for a Diesel engine.
As Diesel engines have no catalytic converters there is no need to remove those additives completely.
I'm very reluctant to praise one or the other engine oil product here as that can be seen as advertising, but it seems that for classic engines a good choice seems to be:
Valvoline VR1 racing oil
which have just released a statement to this here:
Redline sell oil and additives specific to this problem
as well GM seems to seel some stuff called EOS which seems to be the same (just maybe less effective according to ZDDPlus)
Some people use camshaft break-in additives, which seems to work fantastic but has the side effect that it contains graphite that clocks the oil filter.
So break in lube and additives are just for what they are called. Break-in, change filter then drive. I haven't come across a camshaft manufacturer who recommends break-in additives for longer periods.
In short, pick your oil carefully, talk to the car parts store. In most cases the oil bottles will state high ZDDP count if you found the right one.