Thread: Break in oil

First off, I am a noob to the Grand Prix GTP. Just got mine a week ago, but have been pining for one for years. Anyway, I am changing over to synthetic Royal Purple XPR (I am not trying to open the synthetic VS dino conversation again). Now from what I have read and discussed with others, an engine needs zinc and phosporus to help protect the metal on metal areas, IE cylinder walls, flat tappet cam, etc. What I planned on doing during the oil change was adding 4 liters of XPR and the remainder in RP Break In Oil because of its high zinc and phosphorus content.

My questions is this; Can you put too much zinc and/or phosphorus into an engine?

Second, the engine has been rebuilt and has all new seals. I have heard both, "Flush the engine" prior to switching to synthetic and, "It isn't necessary". What is the recommendation of the experts?

Thanks

First, anyone saying that you need to flush to switch to synthetic is about 30 years out of date. There used to be an issue back in the 70s, but not anymore.

Second, you don't have to worry about protecting a flat tappet cam, because you don't have one, it's hydraulic roller. I'm not going to get into the whole ZDDP debate. One side says the high ZDDP levels were really only useful as an anti-oxidant with modern engines, others say that's it's better for engine protection. I've never seen any hard data, so the only answers you'll probably get are going to be opinions.

Royal Purple makes engine break in oil....for new motors....

there is an oil thread that SyntheticShield had a while back.... might want to search for it.

Thank you, but are there not other areas in an engine that could benefit from the ZDDP? (Provided you believe in its ability to act as a protectant)

I have read a study that was put out by Shell regarding their Rotella with ZDDP (it seems that some hobbyists run the Rotella diesel oil in their cars for improved performance) which showed an 0.7 to 1.6 % improvement in fuel economy. That seems insignificant, but what I gather is that an improved fuel economy means less friction which in turn means less heat. Also less soot in the oil prevents the oil from thickening prematurely thus extending the usable life of the oil in the engine. It is also better for cold weather performance and here in Calgary it is not uncommon to have spells of -20 to -30 throughout the winter months.

Please correct me if I am incorrect, because like I said, I am a noob to all of this.

EDIT** Thanks UR LOSN. I understand that break in oil is for new engines. I was only curious because of its ZDDP properties possibly helping prolong the life of the engine.

Is Street Legal Oil Booster (SLOB) still around? I know people use to use it because it's packed with ZDDP. AFAIK, the reason for the reduction of ZDDP in newer oils is because if it makes it's way into the combustion chamber, it'll destroy the cat in short order, something else to be aware of.

As I said, I'm not getting into the debate on whether it's helpful or not, mostly because I don't know myself.

I appreciate the advice. ZDDP will be something that I will be avoiding.