Best ZDDP Levels For Motor Oil?

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52
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Kalifornia
Now that most of the oil makers are being forced to take out zinc compounds (ZDDP), we have aftermarket ZDDP additives available. For old engines with flat tappet cam design, ZDDP is important to prevent cam scoring. Anybody know what the best level for ZDDP is? I recall about 1500 to 2000 ppm was the right ballpark. Is there a downside to adding to much? I seem to recall it caused some kind of problem. maybe you oil experts could clue us in as to the specifics of the ZDDP thing.
 
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Chicago Area
Break in is the biggest concern, by far. And is is NOT flat tappets that are the problem. Most new cars have them. Rollers are rare. It is high spring pressures and high loadings of fast ramp high performance cams that are the problem.
 
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246
Location
Eastern U.S.
I'm thinking about Valvoline VR1 in my Cadillac next time. Kinda sorta maybe. "Valvoline VR1: Contains 75% higher zinc than SM motor oil with a balanced additive package designed to work in both racing and street-legal applications. This product will protect older style push-rod and flat tappet engines. Valvoline provides this product in both multi and mono viscosity grades: 20w50, straight 50, 10w30, straight 30, straight 40, and straight 60." "Valvoline VR1 Racing Oil contains .13% of Zinc and .12% of Phosphorus compared to the Valvoline "Not Street Legal" Racing Oil which contains .14% of Zinc and .13% of Phosphorus." http://www.valvoline.com/faqs/motor-oil/racing-oil/79
 

bountyh

Thread starter
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52
Location
Kalifornia
 Originally Posted By: Rumble
I'm thinking about Valvoline VR1 in my Cadillac next time. Kinda sorta maybe. "Valvoline VR1: Contains 75% higher zinc than SM motor oil with a balanced additive package designed to work in both racing and street-legal applications. This product will protect older style push-rod and flat tappet engines. Valvoline provides this product in both multi and mono viscosity grades: 20w50, straight 50, 10w30, straight 30, straight 40, and straight 60." "Valvoline VR1 Racing Oil contains .13% of Zinc and .12% of Phosphorus compared to the Valvoline "Not Street Legal" Racing Oil which contains .14% of Zinc and .13% of Phosphorus." http://www.valvoline.com/faqs/motor-oil/racing-oil/79
"Valvoline VR1 Racing Oil contains .13% of Zinc and .12% of Phosphorus compared to the Valvoline "Not Street Legal" Racing Oil which contains .14% of Zinc and .13% of Phosphorus." If my math is right, 0.13% is about 1300 PPM (parts per million) which is the ballpark all oils used to be. FYI, the zinc-phosphorous was phased out to prolong the life of the cat converters, something to think about if using "not street legal" oil in a new car. My application is a motorcycle, so I don't have a cat converter. I just want max engine protection.
 
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11,184
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Bad Axe, MI
 Originally Posted By: mechtech2
Break in is the biggest concern, by far. And is is NOT flat tappets that are the problem. Most new cars have them. Rollers are rare.
Huh??? on GM's it's been roller lifters since around 1988 on most apps.... i understaind 1200 ppm is golden
 
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139
Location
So. Cal
My 1990 Chevy Silverado 350 H/O flat tappet engine gets GC (SL rated) with a slug of SX-UP anti-wear additive with plenty of ZDDP. That puts the ZDDP level well over 1000+ ppm. I even used MaxLife Full Syn with a healthy dose of VSOT when it was loaded with zinc a few years ago. Can't find MaxLife Syn any more and the VSOT has been reformulated to a weaker EPA compliant tree hugging version of itself.
 
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1,714
Location
CA.
VSOT was discontinued. I have about 12 bottles dated 1999 that I recently got my hands on. I think that would be before it was tweaked for the tree huggers? AD
 
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497
Location
VA
From what I've read 800 ppm is good up too 600 # OTN lifter load. Break-in is what's important.
 
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