What is ZDDP? Is it required in the older Z engines? I have a 240Z that I just purchased and it has been driven 400 documented miles in the last 2 years. I deparately need to change the oil and want to get knowledgable prior to actually doing it. So far, I have planned to get a factory filter, Still trying to determine the best oil, and questioning oil additives at this point. Until then the car sits in the garage.

Secondary question, does anyone have suggestions for a company that offers replacement radiators in the colorado springs/ denver areas?

Thank you for your input....

Hi Rod,

Just as a suggestion to a new guy on the site, try out the search function! It has answers to just about any question you might think of regarding these old beauties....it a great place to start your research! By the way, welcome aboard and enjoy!!!

Tom

ZDDP has to do with the zinc content in the oil. This has been reduced in recent years to lengthen the life of catylitic converters. ZDDP is of particular importance to aircooled engines such as earlier Porsche and VW motors. I am not aware of the need for higher ZDDP levels in the I6 motor in the Z car... A good reference is the LN Engineering website. Charles Navarro and his wife have done a good deal of research on ZDDP levels. Brad Penn and Royal Purple along with some motorcycle oils have decent levels.

From what I've read in a different thread, having ZDDP in the oil helps reduce the wear on the cam, lifters, and rockers for older engines. I can't remember everything in detail, but I've been runing valvoline VR-1 because of the thread (I think it was on hybridz)

Edited September 4, 200816 yr by m4xwellmurd3r

See this thread for good info on Zinc/Phos. It is very important info all Z owners should know.

Phred

http://forums.hybridz.org/showthread.php?t=137868

I've been mixing mine - 3 quarts of 10W-30 Valvoline VR-1 (what they used to call 'Racing' oil) for the ZDDP content, and a couple of quarts of 10W-30 high mileage oil for the gasket and seal additives. Works well to keep the 36 year old gaskets sealed up. Some day I'll pull the motor to paint and re-seal it, when I do I'll go to all VR-1.

I am not sure if I posted these links in the other thread, but there is some useful information on the Mobil One web site regarding this question:

http://www.mobiloil.com/USA-English/MotorOil/Car_Care/AskMobil/ZDDP_Levels_Classic_Cars.aspx

http://www.mobiloil.com/USA-English/MotorOil/Car_Care/AskMobil/Zinc_Motor_Oils.aspx

As the second link says, he offending metal that has been removed is phosphorus, not zinc. (But since ZDDP contains both, I guess the effect is the same.)

Also follow the link (on both pages) to the PDF document showing the phosphorus content of various oils. I have been running my 240Z on their 0W-40 since last fall. The oil pressure is more consistent, and I feel safer. It probably doesn't really make that much difference however since the real problem is apparently on cars with "flat tappets" (read push rod motors like old school American V8's)

Yeah, the 'flat tappets' thing seems pretty consistent in the reading I've done on this topic. My problem is that I don't see much difference between how a lifter on a pushrod engine running on the cam lobe is different than the end of an L-series rocker pad running on a cam lobe. So I figure I'll err on the side of caution and use oil with ZDDP as long as I can find it easily.

I will admit that I run Mobil 1 in all my other vehicles with great results. If it wasn't for the ZDDP issue, it'd be in the Datsun as well.

Isky Cams includes a flyer with all their new reground cams that it's imperative to break in their new cams with an oil containing ZDDP. I use Valvoline VR-1 racing oil.

The level of ZDDP has been reduced in recent years because of the effect the phosphorus (P) has on the catalytic converter life. The levels went from 1200 ppm P to 800 ppm P.

There is excellent info on this very topic in the latest edition (Fall 2008) of Hagerty's magazine. I just got mine yesterday and it's at home right now. It's the one with vintage racers on the cover. It's not on their Web site yet, however.

Based on what I've read, I run Valvoline VR-1 in my Z as well. Just broke in a new cam, and it put my mind at ease that I had the high zinc content oil in there already.

I have been doing way too much research on oils over the past few weeks- obsessive I know- but it really is one of the most important decisions to be made for our precious cars. I almost picked the VR-1 until I read this below on a very informative site- which may or may not have been mentioned here- it's early and I'm loopy- so sorry if this is a repeat.

Quote from

http://www.zddplus.com/index.htm

tech brief 5- but the whole site is full of great information on everything to do with ZDDP, and oils in general too. These additives (or similar products- as I hear GM has an equivalent product) are engineered specifically to bring the Zinc and Phosphorus content up to levels palatable to our engines- and as such might be a fantastic thing allowing us greater latitude in our choice of oil, being able to supplement an otherwise excellent oil (whatever that may be) with ZDDP to achieve optimal levels. For the record I have no connection whatsoever with this or any other product that has any connection to our cars. Just the facts.

And I reiterate that you all should read through the link Phred mentioned earlier. An *excellent* discussion on this subject, IMHO.

QUOTE-"Racing oils are optimized for short-term severe duty as well as reduced oil drain intervals, in contrast to street-use oil that has been designed for day in, day out street operation with extended drain intervals. Especially in the case of vehicles which see extended periods of storage, it is important to remember that acids and contaminants in the oil are at work even when the car is in storage! In addition to very short oil change intervals, a drag racing engine may have a total life measured in mere thousands of actual crankshaft revolutions between rebuilds. In contrast, street engine may spin a many as 150 million times in 60,000 miles at 2500 rpm, or 7.5 million times per 3000-mile oil change at 2500 rpm! Obviously, the need for long-term protection of all components which rely on the engine oil is much more important in designing a lubricant for street use than it is for racing use." END QUOTE

There is also a concern about the VR-1 formulation not having the additives that keep particles in suspension, something that is not as big a concern with racing situations.

Edited September 5, 200816 yr by Poindexter