I use Amsoil 10W-30 as it states specifically on the bottle for use on motors with flat tappet cams. A little expensive, but at one oil change a season, it is worth it on my Y-Block! 




I love the smell of burning rubber in the morning!

The oil is only part of the equation when eliminating the potential for cam lobe and/or lifter failure.  Here’s the link to a list of items that can contribute to cam and lifter wear/failure and the oil is simply only one of them.
http://www.eatonbalancing.com/blog/2012/11/06/camshaft-and-lifter-failure-causes-2/
 
As a general rule, a flat tappet camshaft will require an oil with at least a 30 viscosity rating (ie: 30W, 5W-30, 10W-30, etc.) for break-in.  The heavier weight oils have a higher film strength which in turn allows the lifter to rotate easier against the action of the camshaft lobes.  While a reduced weight oil may flow better when cold within the confines of a new engine, the shear properties associated with a heavier weight oil are needed where high pressure contact is taking place (lobes/tappets).  That’s the simplified explanation but the brand of oil and its properties have to be at the top of the list.
 
Almost all cam lobe and/or tappet failures start within the first few seconds of an engine firing off but it may take as much as twenty minutes of running for this to come to the forefront if the wear problem is bad enough.  If you can get past that initial fail point, then all is going to be well for many miles.

Lorena, Texas (South of Waco)

I run Valvoline VR1 Racing oil 20w50 conventional.  On the back it states it has high ZDDP levels for use in antique/classic vehicles as well as all flat tappet engines.

1956 Ford Fairlane Town Sedan - 292 Y8 - Ford-O-Matic - 155,000 mi

I use Havolite 20W50 API SJ oil, that has enough ZDDP to a flat tappet engine. 
Recently the Ipiranga oil company also re launched it's 20W40 and 20W50 SJ oils that the labeled "antique car oil"
Since my engine required MS oil from the factory, the good old SJ is kind of a overkill, hahahahahaha.

I also use the Havoline on my S10 with a 4,3 V6, and on my 2001 Ford Focus, with a Zetec 16V 1.8 liter engine. The Focus has 175.000 kilometers on it, what is just above 100K miles, and the engine is like new. Had to replace the catalytic converter once, but that's about all. When you tale the oil filler off, you can see one of the two camshafts, and it's like new. The engine has the same compression Ford lists for a new engine, burns no oil, and has lot's of power (for a tiny 1.8 liter it is).

My '82 Galaxie with a Windsor 302 also uses only Havoline 20W50 SJ. When I bought the car back in 1997, she had 32.000 Kms from new, and today she has 87.000. No change in compression, the engine is very clean, and runs like new. 

Túlio Lazzaroni "FORD", Florianópolis SC Brasil.

'74 Ford Galaxie 500 292 V8

'82 Ford Galaxie Landau 302 V8

'98 Chevrolet S10 4.3 V6

'01 Ford Focus 1.8 Zetec

     I have to agree with you on that there is some good information there , I  have also seen  some guys on speed talk shoot  this down but they have no proof of what there saying,
just lots of talk

Guys,

The above article is actually worth taking the time to read.!!!

Many of us have WRONGLY selected higher viscosity oils thinking they're "better" for break-in and for older engines for many years.
Nothing could be further from the truth.  (As evidenced by the fact that MANY new engine manufacturers use 5W-30 as a factory fill on zero-time engines)    Also the myth of "higher ZDDP"  means better wear protection is still alive, but completely DEBUNKED by the above article.

It's LONG and somewhat boring.   But I strongly suggest anyone wanting to know what oil to use, read it in it's entirety.

Cheers,


Rick






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1955 F-600/272/E4OD// Disclaimer: No animals were injured while test driving my F-600 except the ones I ran over intentionally!

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This post was created using OpenSuSE Linux x64 and Firefox

     When We were  rebuilding my engine  OI contacted Pennzoil to find out what  They recommended  for  a oil for 1950's engines, What they told me was, The best lubrication I could  get for my old engine was a  API  SN grade oil!
 I asked  about  using an oil rated for the older  cars  I was told  those  oils are  obsolete  and do not have adequate  protection for any engine!    The latest grade of oil  has the  best load holding and anti scuff protection than any oil made before!    One more thing I forgot to add was  they were  adamant do not use any additive of  any type, Some additives have chemicals that will work against   the property's of the oil and will decrease the  protection!

There has been so much information and misinformation and myths about oils it's enough to make your head spin.
I have recently read about the not to use diesel oils in gas engines. I was given a huge amount of Delo 10-40 conventional oil about 10 years ago and have been using it in my 223 six ever since with no problems so far..
After rebuilding my 292 I've been using Joe Gibbs HR 10-30 conventional, I'm just not crazy about using synthetics, just a personal choice. BUT! I have been using Valvoline VR1 in my 390FE that has a solid lifter cam for the past three years without any issues.
Here is something to read if you have some extra time.
https://540ratblog.wordpress.com/2013/06/20/

What oil to use in our Y-Blocks always brings up 100 opinions on what is suitable.. Our moderator Ted has reservations about the regular use of Diesel rated oils, and Racing oils are just that, intended for that purpose, not for long term use on the street. For flat tappet engines, the use of modern oils with the  "pin wheel gear" logo on the container, is likely not the best choice, because all those oils are intended for late model "roller valve train" engines with full emission controls. Those oils have reduced anti - scuff  additives, apparently to avoid damaging emission control parts.(government required)  Flat tappet engines need the anti scuff  additives. So, generally speaking, most 10-40 & up oils (without the"pinwheel" on the label) will have adequate anti-scuff additives... As for the use of Synthetics vs regular oils in flat tappet engines, I won't venture an uninformed opinion on that subject..    


Paul

I am(and have been) using Castrol 20-50 with 4 oz of Redline additive each oil change.I change oil every 2 thousand miles.