• Hi Guest!
    You can help ensure that British Car Forum (BCF) continues to provide a great place to engage in the British car hobby! If you find BCF a beneficial community, please consider supporting our efforts with a subscription.

    There are some perks with a member upgrade!
    **Upgrade Now**
    (PS: Subscribers don't see this gawd-aweful banner
Tips
Tips

ZDDP Additive or Oil-incorporated Does it Work???

Hi All,
Sorry for the length but I wanted to provide a wrap-up.

In looking to find a good ZDDP target oil concentration, I came across this web site (https://speedtalk.com/forum/viewtopic.php?f=1&t=35836) that states that testing conducted by oil companies of the day found that, after initial break-in, ZDDP levels above 1400 ppm Increased long term ware and ZDDP levels above 2000
“started attacking the grain boundaries in the iron, resulting in camshaft spalling.” Based upon this information and the fact that improvements have been made in overall additive packages since, I decided that my ZDDP target would be 1,000 – 1,300 ppm.

With this target set, it was my intention to simply use “Castrol GTX 20W50” as the oil for my Healey and eliminate any further consideration of additives.

Castrol GTX 20W50 Conventional Oil P (1,157), Zn (1,422), ZDDP (1,300)
(API SM results 11/05)


However
, I learned that Castrol GTX 20W50 Conventional was reformulated to comply with current API SN specifications and now contains the following reduced levels of P and Zn:

Castrol GTX 20W50 Conventional Oil P ( 754), Zn ( 610), ZDD ( 682)
(API SN results 5/13)

Consequently, an additive, such as ZDDPlus (Z+) P (51,000), Zn(71,000), would be required to boost today’s oil contents to meet my target (see attachment). As you will note in the attachment, based upon the concentrations of P & Zn within the additive and matching the calculations provided in the ZDDPlus technical briefs, 2.3 Oz seems to be sufficient to move 7 quart of Castrol GTX 20W50 Conventional motor oil to a ZDDP of 1300 ppm.

Film Strength
Additionally, this web site (referenced above), and others, also presented an additional oil property that seemed to be as important as ZDDP to the wellbeing of our engines. Measured in psi, Film Strength (FS) represents an oil’s ability to maintain lubricant protective coverage on critical parts during actual operation and the high the FS, the greater the safety-margin the oil will provide to an engine. As presented, values above 90,000 psi provide outstanding protection and seem to be the domain of Racing oils. Motor oils with demonstrated FS values down to 75,000 psi will deliver Good protection with Modest protection for those extending downward to 60,000 psi. Any motor oils with and FS rating below 60,000 psi should be avoided.

Disappointing Additive
It was disheartening to see from their independent oil tests that oils having ZDDPlus added did gain increases in Phosphorous and Zinc (ZDDP) but also experienced a substantial decrease in FS. As stated during their evaluation “Oil companies always say to NEVER add anything to their oils, because adding anything will upset the carefully balanced additive package, and ruin the oil’s chemical composition.” Further, “Adding ZDDPlus SIGNIFICANTLY REDUCED this oil’s wear prevention capability. Just the opposite of what was promised.”

Cold Starting
To add to the complexity of our discussion is the benefit of having a faster cold-starting oil flow. As we all are aware, initial cold starting is one of the most detrimental times in our engine’s operation when protective lubrication is less, or not, present to prevent metal-to-metal ware. Yes, ZDDP would help in this situation but faster coverage of lubrication would be even better. So, as Andrea mentioned, having a 10W or 5W would be more desirable then the 20W we commonly use.

One Alternative
So, if an additive could be detrimental to an oil’s FS but ZDDP is necessary to maintain our Healeys in good operation, what is our alternative? Castrol has introduced an oil that has been designed to support the Classic Car community with Castrol Edge 5W50. This new Syntec formulation is one of a very few I have found stating that its formulation was designed specifically for Classic Cars with appropriate levels of (P 1197, Zn 1257) for an average ZDDP 1200 ppm. Additionally, its FS is above 75,000 and, with a cold start viscosity of 5W, it will provide quicker Cold Start coverage during this critical time when bare metal-to-metal ware has its highest potential. There is a negative, however. At a price of around $10US/Qt, this is more than double the price of the Castrol GTX 20W50 I have most often selected.

Well, I guess that’s about it for me. Sooo … Merry Christmas to all and to all a good night.

Ray (64BJ8P1)
 

Attachments

  • Z+Dosage.jpg
    Z+Dosage.jpg
    21.4 KB · Views: 67
It's been both a education and roller coaster ride with this topic! Many thanks to all that took time to research this important topic. The question now remains, will folks simply run out and continue to buy oil products similar to Castrol 20w 50w at there local Walmart for $15 dollars per 5 gallon container or special order the new classic oils designed for our vintage engines at $80 plus tax per oil change? One note: Some folks refer to our Healeys having a 7 quart oil capacity, Maybe they Refering to a Healey 100 Four banger? I know my big Healeys take every bit of 8 quarts with a new filter.
 
It's been both a education and roller coaster ride with this topic! Many thanks to all that took time to research this important topic. The question now remains, will folks simply run out and continue to buy oil products similar to Castrol 20w 50w at there local Walmart for $15 dollars per 5 gallon container or special order the new classic oils designed for our vintage engines at $80 plus tax per oil change? One note: Some folks refer to our Healeys having a 7 quart oil capacity, Maybe they Refering to a Healey 100 Four banger? I know my big Healeys take every bit of 8 quarts with a new filter.

Do you have the original oil filter and oil pan? I have an after market spin on oil filter, stock oil pan. After I drain the engine oil, I end up replacing about 6 1/2 US quarts. 64 BJ8 phaseII
 
My 67 BJ8 is a 39,000 mile original car, motor never has been out of the car. It has the factory oil pan and a modern spin on filter I installed a few years ago. However, even with the original felt filter it still takes very near 8 quarts to fill to capacity according to my dip stick. The Bentley manual states 15.3 U.S pints =7.650 quarts for 3000 (BN7,BT7) 3000 (BJ7,BJ8) The 100-6 (BN4, BN6) oil capacity is 14.4 U.S pints = 7.200 quarts. The 100-4 oil capacity is 14.11 U.S pints.

Even though the BJ8 oil capacity is just under 8 quarts....I always end up pouring in the full 8 quarts which brings the oil level just a shade over the full mark on the dip stick. If you are only adding 6 1/2 quarts with a new oil filter to your BJ8 then you have been depriving your motor of 1.150 quarts of motor oil! If I where you, I would check to see if you have the proper dip stick!
 
drambuie;916299 Even though the BJ8 oil capacity is just under 8 quarts....I always end up pouring in the full 8 quarts which brings the oil level just a shade over the full mark on the dip stick. If you are only adding 6 1/2 quarts with a new oil filter to your BJ8 then you have been depriving your motor of 1.150 quarts of motor oil! If I where you said:
There are TWO thinking schools-
on the AH 100/6 Longbridge
If people respects the dip stick line you will find a 6-6 1/2 Liter -if you cover the MAX writing on the dip stick
IMG_3180DIP STIKoil.jpgyou find a 7-7 1/2 pint - I prefer to fill 7 or 7 1/2 Liter on my engine, level have a very little increase, but we have more warm dispersion(I have also the oil radiator MOD) and a little oil splash in the basement that can be help in the cold start and haven't contraindication, and we respect the builder indicationsOIL FUEL CAPACITY1.jpg
Actually for my second Oil change, I must decide the definitive oil for my car (I don't agree changes for the future)
I have selected 3 Full Synthetic SHELL - CASTROL - MOBIL 1 --all with 10W60 gradation
MOBIL 1 probably are the best, but actually I never find it in EU continental (only in UK)
SDPT.jpgCDPT.jpgMDPT.jpg I am very hesitant but probably SHEEL will be my choice-- any suggestion pls??
 
Hello Andrea, The Bentley manual specification for oil capacity and my BJ8 dip stick "full"line are the same...7.650 to 7.800 quarts. I simply add the small amount of oil left over and be done with it. After all, our Healeys need a little oil "reserve"to make up for the dripping on the garage floor! Lol.

Getting back to our forum friend "Ausmhly"who says his oil changes take only 6 1/2 quarts for his 64 BJ8...should be interesting to see why he has been adding only 6 1/2 quarts. My first thought was he may have the wrong dip stick with his car! The 100/6 and four cylinder Healey 100 require more oil then that.
 
Hi All,

My BJ8P1 is original in filter and pan. When changing oil and filter, I usually will add 7 qts before starting the engine for a few minutes. I then add additional oil to bring to the high level on the stick. I do not overfill as I expect this would overwhelm the oil slinger and be quickly lost to the garage floor or underside of the car.

For those interested, I just found the genesis article for the site referenced in my previous response (https://540ratblog.wordpress.com/2013/06/20/motor-oil-wear-test-ranking/). Presented by an independent engineer and expert on the subject, he referenced ZDDP as old technology and believes today's additive packages in oil are sufficient to protect our engines. This is a good read.



All the best,
Ray (64BJ8P1)
 
Last edited:
Early 64BJ8 phase1. 6 1/2 US Qts.Plus 4Oz ZDDP. Original dip stick.
Yes, ZDDP is old technology but so is the engine. I wont gamble with my 50 year old engine to save a few bucks once a year.
 
Tahoe Healey, please don’t misunderstand, I totally agree with your point.

In my review of a number of credible articles on this topic, a number of conflicting positions were presented and backed up with logic and data. I still have not come to the conclusion that the new oil formulations and updated additive packages will not provide appropriate protection for my Healey’s engine. In the interim, my intention is to search out and use the Castrol Edge 5W50 (or similar motor oil) that states it has been formulated for Classic Cars.

Personally, I trust that old does not mean obsolete.

All the best to all,
Ray (64BJ8P1)
 
Last edited:
Early 64BJ8 phase1. 6 1/2 US Qts.Plus 4Oz ZDDP. Original dip stick.
Yes, ZDDP is old technology but so is the engine. I wont gamble with my 50 year old engine to save a few bucks once a year.

Is Tahoe Healey 64BJ8 phase1 and myself 64BJ8 phase 2 cars only guys requiring 6 1/2 US quarts for an oil change? I believe my dip stick is also original, correct. I believe the car holds 7.65 US quarts. I assumed some of oil was still in the engine, oil pump and not completely emptying from the oil pan. Maybe I'm not getting a full empty because I am jacking up the front of the car only to get under it?

Some are filling with 8 US quarts? Does the dip stick read past the max line?

Next time I do an oil change, I'll jack up the back of the car too, so the car is level and see if I drain that one quart I seem to be short when replacing the oil.

Cheers,
Roger
 
ZDDPlus comes in a 4oz bottle.

Well that is one way to do it . However, you can avoid the mixing by simply buying any racing oil they were not reformated. One of which is: Valvoline VR1
 
Yep...I just returned from Advance Auto and was reading off the quart bottle...Valvoline Vr1 racing oil 20w 50wt. Made for flat tappet engines and everyday driving! $5.99 per quart.
 
Is Tahoe Healey 64BJ8 phase1 and myself 64BJ8 phase 2 cars only guys requiring 6 1/2 US quarts for an oil change? I believe my dip stick is also original, correct. I believe the car holds 7.65 US quarts. I assumed some of oil was still in the engine, oil pump and not completely emptying from the oil pan. Maybe I'm not getting a full empty because I am jacking up the front of the car only to get under it?

Some are filling with 8 US quarts? Does the dip stick read past the max line?

Next time I do an oil change, I'll jack up the back of the car too, so the car is level and see if I drain that one quart I seem to be short when replacing the oil.

Cheers,
Roger
. Hi Rodger, I really don't see a need to jack up the rear of the car to drain the oil in a level postion with the front. Draining the oil with the car jacked up at the front or on a hoist in level postion will pretty much drain the whole sump as the drain plug is located at the most deepest part of the oil pan anyway. I have done it both ways with the same amount of oil drain. Just change your filter, add your 6 1/2 quarts of new oil as you always do, and start your motor until you get full oil pressure. Shut the motor off wait a few minutes and top off to reach the full mark on the dip stick. It should require 7.6 to 7.8 quarts to bring it to the full mark...with car sitting level. Now...you weren't jacking from the rear of the car to change the oil before where you? Nah.... Just kidding. Let us know your results ok!
 
Just change your filter, add your 6 1/2 quarts of new oil as you always do, and preferably crank the engine using the starter solenoid button until you get full oil pressure. Shut the motor off wait a few minuets and top off if required.

That’s it for me. Sooo … Merry Christmas to all and to all a good night.----KEOKE---Be---:cool:
 
Back
Top