amr89c4

FWIW, many of us have spent considerable time researching suitable engine oils for our '91 and earlier flat tappet engines that require the additive ZDDP or Zinc/Phosphorus to help prevent wear. Cross posted on the 911/964 forums.

Without getting into a mile long thread or debate on the subject, I thought that those interested would enjoy seeing an actual oil analysis of a DE tracked, 3.6 engine.

Notes:
A...20-50 Valvoline VR-1 Racing oil
B...55,000 miles on engine
C...Oil and filter change every 4th event
D...Analysis is from 1,000 track miles on the 2.9 mile road course at Texas World Speedway and the 2.8 mile course at Mid Ohio.
E...The time period was from April thru September of this year.
F...Blue (C) and Yellow (B) run groups
G...Engine pulls hard all the time, rarely falling below 4500 and continually up to 6800, oil temps typically run at the 8:00 position and at the hottest hit the 9:00 position.

Attached are the Blackstone Labs Oil Analysis and PDF Spec sheet from Valvoline on the oil...

rusnak

Fantastic! Thanks!

bgiere

that is a terrific UOA report...i'd be quite pleased with that run. don't change a thing.

scottb

At the risk of igniting the "which oil is best debate," can anyone tell me which are the critical elements, and what what the target levels should be?

Thanks!

amr89c4

Based on my research I concluded for my situation, I was comfortable with 1200 ppm on both Z and P or 0.120%. Trust me, everyone has an opinion.

In this analysis, the VR comes in a little low on the P but is fine on the Z. I want to analyze a couple more samples before I conclude VR-1 is what I will continue to run in the long term.

Here's a link to a very good brief on oil. There are plenty more to be found, but this is the most interesting and author, Navarro runs an air cooled P Car to boot. http://www.lnengineering.com/oil.html

amr89c4

Sorry.......Z&P = Zinc and Phosphorus

ZDDP = zinc dialkyl dithiosphosphate

Steve Weiner-Rennsport Systems

Did you use the off-the-shelf version or the NSL one?

amr89c4

Off the shelf from AutoZone. In fact they had a special on it a couple of months ago and I bought 4 cases of it.

Its interesting in that if you look at the bottle, it looks like its API rated, but its not eg, no starburst seal, but it does indicate it meets or exceeds API SM requirements. According to information I dug up elsewhere, the Z&P content is around 400 ppm too high to meet the 'official' API SM requirement which if I recall is 0.085% or so. They get away with it as its marketed as a very low volume racing oil which typically is used with older cars without 'cats'. Also, it supposedly contains the other dispersants, detergents and corrosion inhibitors that the NSL stuff does not and can go further between changes than the NSL which has a Valvoline recommended interval of around 3 mos or 500 miles.

Dave Mitchell

Guys,

A 911 motor does NOT have a "Flat Tappet" anywhere inside. A flat tappet is not flat. It is slightly oval from the center peak to the outer rim and the cam profile is tapered from side to side. The two work together so the tappet or lifter spins in the bore and does not grind itself "flat". They are very soft in comparison and need the ZDDP additive to help them survive. The 911 cam face along with the rockers are flat side to side and hardened as well. That is why they last so long. With good clean oil and proper oil pressure a 911 cam and direct contact hardened rocker will last far longer than any cam and lifter pushrod type of motor.

Now if you have a 356 then that is a different story and you need the ZDDP for sure.

Steve Weiner-Rennsport Systems

Hi Dave,

With all due respect,.......911 engine's valve gear shares a lot in common with the V-8's flat tappet package regarding the need for sufficient ZDDP.

Until the oil manufacturers began reducing Zn & P from oils about 4 years ago, cams and rockers lasted the life of the engine unless the spray bars became obstructed or a poor grade of oil was used (thats another whole subject).

With the mandated reduction of ZDDP, we've collected a significant number of failed cams and rockers in all 911 engines with mileages ranging from 20K to 80K. Having been in this business since 1975, the difference in the frequency of camshaft failures has been starkly apparent with the changes in oil formulations. I've not even addressed the issues with other engine parts such as intermediate shaft gears, as well.

For these and other reasons, we recommend the use of a premium oil containing 1200ppm of ZDDP for all 911 owners to ensure long engine component life. Naturally, oil change frequency is critical and we advise that the factory oil change recommendations should be shortened up for cars subjected to short trips.

JMHO, so YMMV.

Daniel Dudley

Gee, I wish someone had told My engine that ! I could have saved a TON of money.

I also PPI'd several cars with pitted cams, and I would be happy to tell you that I think the problem is real, and that it has to do with the pressure on the cam lobes, not the type of followers used. I understand that the ZDDP is actually deposited on the metal in instances of extreme pressure, and it is constantly being deposited and sacrificed in such a way as to protect the cam lobes.

It is also worth noting that the need for additional cam lobe protection during break in is pretty well documented on our engines, and that a proper break in helps to prevent premature cam wear, and can extend cam lobe life with borderline oils.

The question is, do you want a cam that may last for 80,000 miles, or a cam that may last the life of your engine ? I do know some old school Porsche mechanics who don't see the zinc issue as a problem - YET. I have been seeing it as a consumer, and I think that a lot of otherwise nice 911s are being put on the market right after a valve adjustment. This makes a PPI on a dry engine fairly critical. Just knowing that the studs are good is not enough anymore.


I don't know a lot, but I am fairly sure of the above.

GothingNC

So how does the VR-1 compare to Brad Penn?

John

amr89c4

I was running BP but it became such a pain and expensive to get down here to Tx that I switched. I was completely happy with it, but had not had the opportunity to run an oil analysis test on it. As I recall it was advertised to be at 1200 ppm on both zinc and phosphorus.

I posted the analysis to show some real Z&P numbers for a change. Granted its low miles, but its hard track miles compared to daily driving.

Thats not to say that daily driving isn't hard on oil, in fact it may well be harder.

amr89c4

Pardon my loose expression. The concern is high valve spring tension/loads and the lubrication of the rocker and cam lobe interface. I'll go the extra mile to provide the surface hardness all the added protection I can to ensure that long life Porsche is famous for.

After all, surface hardening is very shallow and wear is wear. I sleep better knowing I have an oil that meets or exceeds the requirements of the components.

GothingNC

Lynn,

Thanks for the info.

I have a local supplier (Kennedy Oil in Highpoint) that ships charges only $15 in shipping for a case with 2 day delivery, a little less per case when order more.

It comes out to about the same price as as the Vavoline VR-1 at the local Autozone.

John