The 327 is needing it's first oil change. Still has the Lucas break in high zinc oil in it, along with half a bottle of Comp break in additive. I took no chances on the cam break in, and it appears to have worked just fine.
I have a high volume oil pump, no bypass filter adapter, and will always run a no bypass extra large 6002 K&N filter.
Now I do have what I think is a mainseal or rear pan leak, which I'll have to investigate and stop at some point less it fouls the clutch. The car will be driven on nice days through the winter.
What oil would you run? Would you still be adding the Comp zinc additive?
All opinions welcome. I know this question can be very subjective.
Thanks, Mark
The break in combo,
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65 Laurentian post, 67 Grande Parisienne 4 door HT.
Mark, you are correct about the subjectivity of your oil question. I am positive that many others will chime it, but here is what my mechanic of 35 plus years recommended that I use in the custom built 396 Dart engine in my CS. I have been using this for over 5 years and have had no issues whatsoever.
Ive always used a good quality dyno oil with gm EOS.
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63 Parisienne sport coupe (The Big GTO), black, maroon interior, 409 4 speed; former owner of a 59 El Camino, 63 Corvette SWC, 62 Chev Bel Air SC. 1963- Pontiac top selling car in Canada
Mahone Bay, NS Still not old enough to need an automatic
I attended a good presentation at POCI Fort Worth in 2017 put on by Driven Oil. The idea of just pouring in some zinc additive isn't very scientific, it's best to have the appropriate amount formulated. I have been using Lucas Hot Rod & Classic oil.
I have only used EOS for 20 years and know hundreds of old Chevy guys who use it as well, all with no cam issues. GM recommended it on flat tapper cams when this oil issue came up after zinc started fouling catalytic converters when they were mandated in the mid 70s.
There are plenty of theories on zinc and oil, pick one you like?
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63 Parisienne sport coupe (The Big GTO), black, maroon interior, 409 4 speed; former owner of a 59 El Camino, 63 Corvette SWC, 62 Chev Bel Air SC. 1963- Pontiac top selling car in Canada
Mahone Bay, NS Still not old enough to need an automatic
X 2. This is what my 396 builder for the Grande told me to use and suggested the 15 W 50 Driven. I am using a 10 W 30 Driven in my 78 Square 350 with a Lunati flat tappet, so far so good.
Ok, here is a question and no intention to hijack the thread.
But, we know that oil has had zinc removed from the formula over the years and now there is hot rod oil with zinc, EOS, zinc additives galore, etc for your old flat tappet hot rod engine.
But, can anyone tell me why all these old grain trucks / farm trucks with flat tappet cams in 366's, 427', 350's etc and other brands (Ford etc) still run on zincless oil of today and not fail the cam?
For example, my brother has a 76 C65 with a 366 and uses regular 10 W 30 oil and I can assure you he doesn't even know what EOS is and yet the flat tappet cam doesn't fail, years and years after zinc no longer exists in regular conventional oil?
Ok, here is a question and no intention to hijack the thread.
But, we know that oil has had zinc removed from the formula over the years and now there is hot rod oil with zinc, EOS, zinc additives galore, etc for your old flat tappet hot rod engine.
But, can anyone tell me why all these old grain trucks / farm trucks with flat tappet cams in 366's, 427', 350's etc and other brands (Ford etc) still run on zincless oil of today and not fail the cam?
For example, my brother has a 76 C65 with a 366 and uses regular 10 W 30 oil and I can assure you he doesn't even know what EOS is and yet the flat tappet cam doesn't fail, years and years after zinc no longer exists in regular conventional oil?
How many miles do these old grain trucks / farm trucks get put on them each year? I suspect very few, like under 1000. I also suspect that's why they're not seeing camshaft failure.
I have seen cam's come out of flat tappet engines running modern oil where the lobe is non-existent. The modern oil just couldn't handle the extreme pressure of the lifter / lobe contact.
Maybe the old old cams didnt have the big lifts that the newer cams run? And I suspect they only run low kms as well like Clint said. Who knows, maybe the metal in the old low lift cams was also better quality.
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63 Parisienne sport coupe (The Big GTO), black, maroon interior, 409 4 speed; former owner of a 59 El Camino, 63 Corvette SWC, 62 Chev Bel Air SC. 1963- Pontiac top selling car in Canada
Mahone Bay, NS Still not old enough to need an automatic