ZDDP classic oil

[Burdekin]

Going to be changing my cam soon so looking at high zinc classic oils, from Tinus Tuning Ben has this list:

- Castrol classic 20w50: ca. 0.16% ZDDP - MPM classic 20w50: ca. 0.12% ZDDP
- MPM 20w50 High Zinc ca. 0.30% ZDDP - Millers classic 20w50: ca. 0.18% ZDDP - Motul classic 20w50: ca. 0.19% ZDDP - Penrite classic 20w50: 0.21% ZDDP
- ELF HTX Retro 2 20w50: 0.07% ZDDP
- Valvoline VR-1 20w50: ca. 0.23% ZDDP - Swepco 306 20w50: ca. 0.25% ZDDP
- Brad Penn 20w50: ca. 0.25% ZDDP
- Porsche Classic 20w50: ca. 0.18% ZDDP

MPM high zinc is even cheaper than Halfords so will give it a try.

https://www.ebay.co.uk/itm/ENGINE-OI...QAAOSwrIxeedDh

[c1800]

That’s a wide and varied list, from .30% to .07%. Lots of opinions out there (here) but it “appears” from my extensive research somewhere between .10% and .13% is the desired range for Zinc and Phosphorous for regular running and after break-in. I use this:

http://pqiadata.org/NAPA_15W40.html

And too much ZDDP is a bad thing for regular use, and break-in . Google “too much ZDDP” and you’ll find some interesting reading.

Good luck.

[Burdekin]

“In the past, ZDDP has been added up to approximately 0.5%. However, research showed that a value of approximately 0.3%on average gave the best protection, although again dependent on the interaction with other additives. Partly due to the advent of the catalyst and stricter environmental requirements, the content of ZDDP is the lastfor decades. Due to improved motors, the pressure loads in a typical motor are more realalso greatly reduced, so that a good oil film can always be maintained and no need for the 'back-up'of ZDDP exists anymore. Unfortunately, this is different for many older motorcycles. Especially on the contact surface betweenthe cams of the camshaft and the cam followers it is very difficult with the older engines to get a good oil filmpreserve. Without sufficient backup of the ZDDP, very heavy wear can result.

Additionally: Break-in oils often have a very low ZDDP on purpose. However, ZDDP is sufficient for the camshaft and followers especially when walking in is very important. Tinustuning supplies a very good running-in oil with increased ZDDP (0.29%). Crucial for running in! For your information: Some examples of cam follower wear of standard Volvo B18 / 20/30 cam followers ('age' between 1,000 and 200,000 km)Ps. The above ZDDP values ​​of the oils have been partly calculated on the basis of data from Zinc oronly Phosphorus (not pure ZDDP). When someone has more (or different) values, especially othersoils, I keep recommended!” Tinus Tuning

[Burdekin]

Worth a read: https://translate.googleusercontent....8RT3hp0nh0dlpw

[142 Guy]

ZDDP - that is always a fun topic for an inconclusive debate.

When talking about % values you need to clarify whether the percentage is by volume or by weight. I have seen references to both. I think percentage by weight is the more common number; but, if you see significant differences in values its useful to check to see if they are referring to weight or volume.

In North America, the more common reference appears to be parts per million which I assume is ppm based upon weight (ppm is unitless and can be by weight or by volume). Most common motor oils meeting the latest API standards have zinc and phosphorous contents in the 700 - 1000 ppm range. That would be equivalent to 0.07 - 0.10 % by weight which seems to be the common range for modern oils when referenced by weight.

I believe the latest API standard sets an upper limit for phosphorous at around 800 ppm. The amount of Zn can go higher; but, you need the magic Zn+P combo to get the anti wear function. Oil formulators may bump the Zn up because it has anti oxidation benefits. The interesting part about the API standards is that the low P limit only applies to certain weights of oils so you can get oils meeting SM or SN standards with higher P levels if you pick your weights judiciously.

As far as I am aware, there are no published standards or engineering practices outlining minimum levels of ZN and P to achieve specified levels of wear protection. I am sure that the oil manufacturers have their own internal analysis as part of their internal testing. There is lots of internet wisdom and opinion on the required level of ZDDP for flat tappet engines with a range of 1000 - 1400 ppm being a common range for good protection. The other common theme you can find is that too much ZDDP is a bad thing because it can become corrosive. The internet wisdom on the upper limit on ZDDP seems to be in the 1500 - 2000 ppm range.

Mobil lists the Zn and P concentrations for their range on Mobil 1 oils.

file:///C:/Users/Neil/AppData/Local/Temp/MicrosoftEdgeDownloads/60933d1b-8d52-479b-8bd0-1afa9648cabc/mobil-1-product-guide-rev-31.pdf

If you want, you can go Zn and P heavy. Basic Mobil 1 15W-50 has a P of 1200 ppm and if you want to use the race only oils you can go up to 1750 ppm. Their advice against the use of the race oils in non race applications probably relates to the corrosive nature of high P levels and the assumption that high wear is a greater evil than corrosion in a race engine and that race engines get their oil changed after every race anyway.

The note in the first post about Valvoline VR1 having a ZDDP value of 0.23% is interesting as Valvoline's website lists VR1 at 0.12% P & 0.13%Zn.

https://www.valvoline.com/about-us/f...%20contains%20.

The only real take-away that I have is that the API oil standards include wear tests. As the API standards have changed up to the current SN standard the performance of oil in terms of the wear tests has not degraded. The new oils perform as well as or better than the old SA - SD oils in use at the time when flat tappets were common. As ZDDP has dropped the formulators have added different packages that improve wear performance. The only argument that could be made is that the API tests don't accurately model wear on a flat tappet interface; however, in the great ZDDP debate I don't think I have seen that argument.

[Burdekin]

Worth noting Ben of Tinus Tuning is one of the premier B18/20 builders and manufacturer of cams. This is his trade and speciality, I've dealt with him and comfortable he knows his stuff. 👍