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Old 09-10-2019, 11:43 AM   #1
Furno68C20
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Should I be using ZDDP Oil in my 327?

Just wondering if I should be using ZDDP oil? My engine has been rebuild but don't know if the cam is a Flat tappet or roller. What oil do you guys prefer on stock engines vs rebuild?
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Old 09-10-2019, 12:07 PM   #2
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Re: Should I be using ZDDP Oil in my 327?

I'd use a zinc additive in any flat tappet cam engine, regardless of what oil you are using, to be safe!!!
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Old 09-10-2019, 03:21 PM   #3
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Re: Should I be using ZDDP Oil in my 327?

^^^^^^^^^^^^^^^What he said 100%^^^^^^^^^^^^^
If you don't know.... assume it is a flat tappet cam.
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Old 09-10-2019, 04:34 PM   #4
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Re: Should I be using ZDDP Oil in my 327?

yeah I rather be safe then sorry. Can you add additive to "off the shelf" oil? or is it just best to buy high zinc low detergent oil?
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Old 09-10-2019, 04:54 PM   #5
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Re: Should I be using ZDDP Oil in my 327?

Valvoline VR1 Racing Oil has ZDDP included. I use straight 30 weight in my '68 292 L6.
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Old 09-10-2019, 06:55 PM   #6
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Re: Should I be using ZDDP Oil in my 327?

Shell Rotella T is good enough too. I scored 8 cases of VR1 for $13.xx shipped by Amazon some months back....so I'm good to go in the Chevelle and C10 for 3-4 years.
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Old 09-10-2019, 08:11 PM   #7
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Re: Should I be using ZDDP Oil in my 327?

I just use the Lucas ZDDP additive with off the shelf oil. Pretty affordable.
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Old 09-11-2019, 08:26 AM   #8
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Re: Should I be using ZDDP Oil in my 327?

I replace one quart of my current oil, (not this), with a quart of Lucas oil treatment. Would it be appropriate to add the Lucas product with this oil too? Thinking of switching from the Royal Purple I use. Thanks
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Old 09-11-2019, 09:15 AM   #9
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Re: Should I be using ZDDP Oil in my 327?

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Originally Posted by Willys_MB View Post
I just use the Lucas ZDDP additive with off the shelf oil. Pretty affordable.
Ditto, I buy what ever brand name and proper weight is on sale in the 1.25 gallon jug and add the Lucas ZDDP. I have also found what ever I need pretty cheap also on Amazon and they bring it to me, no chasing it down.
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Old 09-11-2019, 09:02 PM   #10
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Re: Should I be using ZDDP Oil in my 327?

If you dont know if the engine has a roller cam in it or not...run the ZDDP additive...it wont hurt the roller engine...

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Old 09-23-2019, 10:22 PM   #11
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Re: Should I be using ZDDP Oil in my 327?

This is what I use and have no problems at highway speeds at 3k plus just to stay at 60-65mph. My 350 engine has been rebuilt with 305 heads to bump the compression. I run Mobile 91 octane and try to change oil every 3k miles.
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Old 09-23-2019, 10:40 PM   #12
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Re: Should I be using ZDDP Oil in my 327?

-
I'm going to try the VR-1 in my '68 pickup with the 327 & my '36 Ford with the 327. I have been using an additive but I've been doing some reading on it and the consensus seems to be that the oils with it already added is better than adding it to conventional oils.

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Old 09-24-2019, 02:19 AM   #13
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Re: Should I be using ZDDP Oil in my 327?

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Old 09-24-2019, 08:00 AM   #14
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Re: Should I be using ZDDP Oil in my 327?

This is from GM.

Over the years there has been an overabundance of engine oil myths. Here are some facts you may want to pass along to customers to help debunk the fiction behind these myths.

The Pennsylvania Crude Myth -- This myth is based on a misapplication of truth. In 1859, the first commercially successful oil well was drilled in Titusville, Pennsylvania.
A myth got started before World War II claiming that the only good oils were those made from pure Pennsylvania crude oil. At the time, only minimal refining was used to make engine oil from crude oil. Under these refining conditions, Pennsylvania crude oil made better engine oil than Texas crude or California crude. Today, with modern refining methods, almost any crude can be made into good engine oil.

Other engine oil myths are based on the notion that the new and the unfamiliar are somehow "bad."

The Detergent Oil Myth -- The next myth to appear is that modern detergent engine oils are bad for older engines. This one got started after World War II, when the government no longer needed all of the available detergent oil for the war effort, and detergent oil hit the market as �heavy-duty� oil.

Many pre-war cars had been driven way past their normal life, their engines were full of sludge and deposits, and the piston rings were completely worn out. Massive piston deposits were the only thing standing between merely high oil consumption and horrendous oil consumption. After a thorough purge by the new detergent oil, increased oil consumption was a possible consequence.
If detergent oils had been available to the public during the war, preventing the massive deposit buildup from occurring in the first place, this myth never would have started. Amazingly, there are still a few people today, 60 years later, who believe that they need to use non-detergent oil in their older cars. Apparently, it takes many years for an oil myth to die.

The Synthetic Oil Myth -- Then there is the myth that new engine break-in will not occur with synthetic oils. This one was apparently started by an aircraft engine manufacturer who put out a bulletin that said so. The fact is that Mobil 1 synthetic oil has been the factory-fill for many thousands of engines. Clearly, they have broken in quite well, and that should put this one to rest.

The Starburst Oil Myth -- The latest myth promoted by the antique and collector car press says that new Starburst/ API SM engine oils (called Starburst for the shape of the symbol on the container) are bad for older engines because the amount of anti-wear additive in them has been reduced. The anti-wear additive being discussed is zinc dithiophosphate (ZDP).

Before debunking this myth, we need to look at the history of ZDP usage. For over 60 years, ZDP has been used as an additive in engine oils to provide wear protection and oxidation stability.

ZDP was first added to engine oil to control copper/lead bearing corrosion. Oils with a phosphorus level in the 0.03% range passed a corrosion test introduced in 1942.

In the mid-1950s, when the use of high-lift camshafts increased the potential for scuffing and wear, the phosphorus level contributed by ZDP was increased to the 0.08% range.

In addition, the industry developed a battery of oil tests (called sequences), two of which were valve-train scuffing and wear tests.

A higher level of ZDP was good for flat-tappet valve-train scuffing and wear, but it turned out that more was not better. Although break-in scuffing was reduced by using more phosphorus, longer-term wear increased when phosphorus rose above 0.14%. And, at about 0.20% phosphorus, the ZDP started attacking the grain boundaries in the iron, resulting in camshaft spalling.

By the 1970s, increased antioxidancy was needed to protect the oil in high-load engines, which otherwise could thicken to a point where the engine could no longer pump it. Because ZDP was an inexpensive and effective antioxidant, it was used to place the phosphorus level in the 0.10% range.

However, phosphorus is a poison for exhaust catalysts. So, ZDP levels have been reduced over the last 10-15 years. It's now down to a maximum of 0.08% for Starburst oils. This was supported by the introduction of modern ashless antioxidants that contain no phosphorus.

Enough history. Let's get back to the myth that Starburst oils are no good for older engines. The argument put forth is that while these oils work perfectly well in modern, gasoline engines equipped with roller camshafts, they will cause catastrophic wear in older engines equipped with flat-tappet camshafts.

The facts say otherwise.

Backward compatability was of great importance when the Starburst oil standards were developed by a group of experts from the OEMs, oil companies, and oil additive companies. In addition, multiple oil and additive companies ran no-harm tests on older engines with the new oils; and no problems were uncovered.

The new Starburst specification contains two valve-train wear tests. All Starburst oil formulations must pass these two tests.

- Sequence IVA tests for camshaft scuffing and wear using a single overhead camshaft engine with slider finger (not roller) followers.

- Sequence IIIG evaluates cam and lifter wear using a V6 engine with a flat-tappet system, similar to those used in the 1980s.

Those who hold onto the myth are ignoring the fact that the new Starburst oils contain about the same percentage of ZDP as the oils that solved the camshaft scuffing and wear issues back in the 1950s. (True, they do contain less ZDP than the oils that solved the oil thickening issues in the 1960s, but that's because they now contain high levels of ashless antioxidants not commercially available in the 1960s.)
Despite the pains taken in developing special flat-tappet camshaft wear tests that these new oils must pass and the fact that the ZDP level of these new oils is comparable to the level found necessary to protect flat-tappet camshafts in the past, there will still be those who want to believe the myth that new oils will wear out older engines.
Like other myths before it, history teaches us that it will probably take 60 or 70 years for this one to die also.

Special thanks to GM's Techlink
- Thanks to Bob Olree � GM Powertrain Fuels and Lubricants Group
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Old 09-24-2019, 02:41 PM   #15
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Re: Should I be using ZDDP Oil in my 327?

I have been running NAPA 10W30 motor oil (made by Ashland Oil Co, who makes Valvoline) in my truck with a stock 250 engine for 100,000 miles with no ill effects. The engine had about 5,000 miles on a reman long block when I bought the truck.
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Old 09-24-2019, 03:07 PM   #16
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Re: Should I be using ZDDP Oil in my 327?

Dah...............yes and good oil too..........vr1
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Old 09-24-2019, 05:11 PM   #17
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Re: Should I be using ZDDP Oil in my 327?

Quote:
Originally Posted by 72c20customcamper View Post
This is from GM.

Over the years there has been an overabundance of engine oil myths. Here are some facts you may want to pass along to customers to help debunk the fiction behind these myths.

The Pennsylvania Crude Myth -- This myth is based on a misapplication of truth. In 1859, the first commercially successful oil well was drilled in Titusville, Pennsylvania.
A myth got started before World War II claiming that the only good oils were those made from pure Pennsylvania crude oil. At the time, only minimal refining was used to make engine oil from crude oil. Under these refining conditions, Pennsylvania crude oil made better engine oil than Texas crude or California crude. Today, with modern refining methods, almost any crude can be made into good engine oil.

Other engine oil myths are based on the notion that the new and the unfamiliar are somehow "bad."

The Detergent Oil Myth -- The next myth to appear is that modern detergent engine oils are bad for older engines. This one got started after World War II, when the government no longer needed all of the available detergent oil for the war effort, and detergent oil hit the market as �heavy-duty� oil.

Many pre-war cars had been driven way past their normal life, their engines were full of sludge and deposits, and the piston rings were completely worn out. Massive piston deposits were the only thing standing between merely high oil consumption and horrendous oil consumption. After a thorough purge by the new detergent oil, increased oil consumption was a possible consequence.
If detergent oils had been available to the public during the war, preventing the massive deposit buildup from occurring in the first place, this myth never would have started. Amazingly, there are still a few people today, 60 years later, who believe that they need to use non-detergent oil in their older cars. Apparently, it takes many years for an oil myth to die.

The Synthetic Oil Myth -- Then there is the myth that new engine break-in will not occur with synthetic oils. This one was apparently started by an aircraft engine manufacturer who put out a bulletin that said so. The fact is that Mobil 1 synthetic oil has been the factory-fill for many thousands of engines. Clearly, they have broken in quite well, and that should put this one to rest.

The Starburst Oil Myth -- The latest myth promoted by the antique and collector car press says that new Starburst/ API SM engine oils (called Starburst for the shape of the symbol on the container) are bad for older engines because the amount of anti-wear additive in them has been reduced. The anti-wear additive being discussed is zinc dithiophosphate (ZDP).

Before debunking this myth, we need to look at the history of ZDP usage. For over 60 years, ZDP has been used as an additive in engine oils to provide wear protection and oxidation stability.

ZDP was first added to engine oil to control copper/lead bearing corrosion. Oils with a phosphorus level in the 0.03% range passed a corrosion test introduced in 1942.

In the mid-1950s, when the use of high-lift camshafts increased the potential for scuffing and wear, the phosphorus level contributed by ZDP was increased to the 0.08% range.

In addition, the industry developed a battery of oil tests (called sequences), two of which were valve-train scuffing and wear tests.

A higher level of ZDP was good for flat-tappet valve-train scuffing and wear, but it turned out that more was not better. Although break-in scuffing was reduced by using more phosphorus, longer-term wear increased when phosphorus rose above 0.14%. And, at about 0.20% phosphorus, the ZDP started attacking the grain boundaries in the iron, resulting in camshaft spalling.

By the 1970s, increased antioxidancy was needed to protect the oil in high-load engines, which otherwise could thicken to a point where the engine could no longer pump it. Because ZDP was an inexpensive and effective antioxidant, it was used to place the phosphorus level in the 0.10% range.

However, phosphorus is a poison for exhaust catalysts. So, ZDP levels have been reduced over the last 10-15 years. It's now down to a maximum of 0.08% for Starburst oils. This was supported by the introduction of modern ashless antioxidants that contain no phosphorus.

Enough history. Let's get back to the myth that Starburst oils are no good for older engines. The argument put forth is that while these oils work perfectly well in modern, gasoline engines equipped with roller camshafts, they will cause catastrophic wear in older engines equipped with flat-tappet camshafts.

The facts say otherwise.

Backward compatability was of great importance when the Starburst oil standards were developed by a group of experts from the OEMs, oil companies, and oil additive companies. In addition, multiple oil and additive companies ran no-harm tests on older engines with the new oils; and no problems were uncovered.

The new Starburst specification contains two valve-train wear tests. All Starburst oil formulations must pass these two tests.

- Sequence IVA tests for camshaft scuffing and wear using a single overhead camshaft engine with slider finger (not roller) followers.

- Sequence IIIG evaluates cam and lifter wear using a V6 engine with a flat-tappet system, similar to those used in the 1980s.

Those who hold onto the myth are ignoring the fact that the new Starburst oils contain about the same percentage of ZDP as the oils that solved the camshaft scuffing and wear issues back in the 1950s. (True, they do contain less ZDP than the oils that solved the oil thickening issues in the 1960s, but that's because they now contain high levels of ashless antioxidants not commercially available in the 1960s.)
Despite the pains taken in developing special flat-tappet camshaft wear tests that these new oils must pass and the fact that the ZDP level of these new oils is comparable to the level found necessary to protect flat-tappet camshafts in the past, there will still be those who want to believe the myth that new oils will wear out older engines.
Like other myths before it, history teaches us that it will probably take 60 or 70 years for this one to die also.

Special thanks to GM's Techlink
- Thanks to Bob Olree � GM Powertrain Fuels and Lubricants Group
This quote is more than 15 years old and at the time it was controversial. (See first link) In the time since it was originally published the API ( Starburst logo) has change the specifications for oil at least twice. (See second link)

So in answer to the OP's question. You should run an oil with higher Zinc.

I also recommend not running an Zinc additive in your oil unless you are a chemical engineer. Better to have an oil and Zinc/phosphorus package designed from the ground up to be chemically compatible under all conditions.

https://www.bobistheoilguy.com/forum...Number=1165736

http://www.pqiamerica.com/apiserviceclass.htm
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Old 09-24-2019, 05:43 PM   #18
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Re: Should I be using ZDDP Oil in my 327?

Direct quote from the valvoline site
"What is the controversy surrounding the amount of zinc in motor oil?

The controversy exists as a result of many hands-on car enthusiasts and engine experts belief that lower levels of zinc in API SN and SM motor oils can cause excessive wear in older style push-rod and flat-tappet engines. They hold this belief despite the fact that all new motor oil classifications are intended to be backward compatible."

https://www.valvoline.com/about-us/faq/racing-oil-faq

So it's as clear as mud .
Alot of my cars have well over 100k on them all using name brand oils. Weather its Mobil , Pennzoil ect. Never had an oil related break down .
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Old 09-24-2019, 06:11 PM   #19
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Re: Should I be using ZDDP Oil in my 327?

I,ve had cam lobe problemsl along with excessive valve guide wear first hand but do as you please...............
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Old 09-24-2019, 06:46 PM   #20
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Re: Should I be using ZDDP Oil in my 327?

Quote:
Originally Posted by Cali72K20 View Post
This is what I use and have no problems at highway speeds at 3k plus just to stay at 60-65mph. My 350 engine has been rebuilt with 305 heads to bump the compression. I run Mobile 91 octane and try to change oil every 3k miles.
Same here! been using VR1 for a long time. I use Wix filters which is also what the Napa gold filters are.
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Old 09-24-2019, 06:47 PM   #21
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Re: Should I be using ZDDP Oil in my 327?

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I,ve had cam lobe problemsl along with excessive valve guide wear first hand but do as you please...............
If this is directed at me let me I look at all sides of an issue.

But in the 70s i rebuilt plenty of motors with very sloppy mains and warn out guides so this isn't something new engines wear out. Most times it from oil starvation. Clogged pushrod and passages
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Old 09-24-2019, 06:52 PM   #22
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Re: Should I be using ZDDP Oil in my 327?

On a side note there are millions of over head cam engines where the cam actuated the valve directly or from a rocker with no rollers. Don't see a lot of failures .

A car in the 70s with over70k not having issues was rare.
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Old 09-24-2019, 10:18 PM   #23
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Re: Should I be using ZDDP Oil in my 327?

Quote:
Originally Posted by 72c20customcamper View Post
This is from GM.

Over the years there has been an overabundance of engine oil myths. Here are some facts you may want to pass along to customers to help debunk the fiction behind these myths.

Special thanks to GM's Techlink
- Thanks to Bob Olree � GM Powertrain Fuels and Lubricants Group
Good information - thanks!
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Old 09-25-2019, 01:41 AM   #24
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Re: Should I be using ZDDP Oil in my 327?

Quote:
Originally Posted by HO455 View Post
This quote is more than 15 years old and at the time it was controversial. (See first link) In the time since it was originally published the API ( Starburst logo) has change the specifications for oil at least twice. (See second link)

So in answer to the OP's question. You should run an oil with higher Zinc.

I also recommend not running an Zinc additive in your oil unless you are a chemical engineer. Better to have an oil and Zinc/phosphorus package designed from the ground up to be chemically compatible under all conditions.

https://www.bobistheoilguy.com/forum...Number=1165736

http://www.pqiamerica.com/apiserviceclass.htm
Your point about mixing your own makes good sense to me. If I remember right, the link I posted above says over 1400 zinc parts per million (PPM) damages the engine. I run Mobil 1 5W-30 only, which is 900 PPM.

On a side, my engine speaks to me when she likes her liquid, and it purred best on 20-50 Durablend. Only 750 PPM I see. I'm no expert by a long shot, but I can say my cam looks great after 40K miles. I switched to Mobil 1 last two oil changes, simply because it was recommended by a few and Durablend became a pain to buy.
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Last edited by 71CHEVYSHORTBED402; 09-25-2019 at 01:49 AM.
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Old 09-25-2019, 07:49 AM   #25
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Re: Should I be using ZDDP Oil in my 327?

My uncle rebuilt the engine in my truck at some point in the past. Wish I would had listen to the details of when. He couldn't remember what year, just the name of a player in the super bowl that year. I believe it was in the 90's.

Back on point. This engine has been run on Mobile 1 5W-30 synthetic since the rebuild, and I intend to keep it that way. If I change the cam, I might break it in with a high zinc break in oil. Depends what the manufacturer recommends. After that, it will be back to Mobile 1.
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