oil for 79 ????
 

Perhaps I didn't do it right but couldn't find a good oil thread this morning. Been a LONG time since I changed it, so next year it is. (driven rarely) Has about 76K miles. I'm now in the synthetic camp, even use it in lawnmowers.
I know the subject is like politics and religion but I'm open to opinion.

I use Valvoline 5W50 VR1. It´s an racing oil with lot of zinc so use it in cars without cats.
My oil consumption is less than before with the 10w40 stock oil. I drove 1800 km since the last oil change and oil is in the middle of the dipstick between high and low. Engine has 10.000 km since rebuild and i drive fast.

I change oil every 10.000 km.

https://sharena21.springcm.com/Publi...b-ac162d889bd1

I suggest to use 20 W 50 Valvoline VR 1 Racing oil,
since most of your driving will be in warm weather you will be fine with this choice,
you can get it in either Dino or Synthetic blends,
available at most FLAPS.
I dont think that 5W 50 is a good choice unless your driving in subzero temps

Instead of another thread of people rationalizing what oil they use, let's paint this in broad strokes:
Any 20-50 that has a zinc and phosphorus content of 1200-1600 ppm.
If you live where it snows and gets cold (and you drive your 928 in the cold), you can use 15-50, with the same zinc and phosphorus content (and you can leave this oil in, in the summertime.)
If you live where it gets damn cold (and you drive your car in the damn cold), you can use 10-50 or even 10-40, with the same zinc and phosphorus content (but you will want to change back to 20-50 in the summertime.....unless the summertime is at the poles.)

I would be careful with a "racing oil" (sorry Stan), due to the reduced amount of detergents generally present....unless you plan on changing your oil quite often.

https://540ratblog.wordpress.com/ read this and know alot about oil.

Good thread- all duly noted for 2022 when my 79 returns to life.

I copy and pasted this info from that link provided

13. DO COMPARABLE ZINC LEVELS PROVIDE COMPARABLE WEAR PROTECTION?

Some folks have a hard time accepting certain data that has come out of the motor oil “wear testing” that I’ve been performing. The result that is the hardest for them to accept is the outcome showing that an oil with a high level of zinc, will not automatically provide excellent wear protection. That runs counter to everything they’ve always been told over the years.

The data I’ve provided up to now has always included low zinc modern API certified oils along with traditional high zinc High Performance and Racing oils. But having so many oils of different types of oil in the same test, might be a bit overwhelming or confusing. So, here I’ve selected only 13 oils that all have between 1100 and 1800 ppm zinc. That way the comparison is just apples to apples. Now zinc levels vs wear protection can easily be compared straight across.

The excellent performance of many of these high zinc oils, shows that my testing equipment and test procedure do in fact, allow high zinc oils to perform as well as they are capable of performing.

Wear protection categories are:

• Over 105,000 psi = INCREDIBLE wear protection

• 90,000 to 105,000 psi = OUTSTANDING wear protection

• 75,000 to 90,000 psi = GOOD wear protection

• 60,000 to 75,000 psi = MODEST wear protection

• Below 60,000 psi = UNDESIRABLE wear protection

I’ve also included detergent levels for reference as well.

All the oils below are full synthetic unless otherwise specified.

The following group of 13 oils are ranked according to their “load carrying capacity/film strength”, or in other words, their “wear protection” performance, at 230*F. The higher the psi number, the better the wear protection. The tests were repeated multiple times for each oil, and then those results were averaged to arrive at the final psi numbers shown below. And every single oil was tested EXACTLY THE SAME.


1. 10W30 Valvoline NSL (Not Street Legal) Conventional Racing Oil = 103,846 psi
zinc = 1669 ppm
total detergent = 1618 ppm
detergent ppm/zinc ppm ratio = 1.0
NOTE: Due to its very low TBN value, this oil is only suitable for short term racing use, and is not suitable for street use.

2. 10W30 Valvoline VR1 Conventional Racing Oil (silver bottle) = 103,505 psi
(.3% below no.1)
zinc = 1472 ppm
total detergent = 2787 ppm
detergent ppm/zinc ppm ratio = 1.9

3. 10W30 Valvoline VR1 Synthetic Racing Oil, API SL (black bottle) = 101,139 psi
(2.6% below no.1)
zinc = 1180 ppm
total detergent = 2683 ppm
detergent ppm/zinc ppm ratio = 1.9

4. 10W30 Amsoil Z-Rod Oil = 95,360 psi
(8.2% below no.1)
zinc = 1431 ppm
total detergent = 2927 ppm
detergent ppm/zinc ppm ratio =2.05. 10W30 Joe Gibbs HR4 Hotrod Oil = 86,270 psi
(16.9% below no.1)
zinc = 1247 ppm
total detergent = 3134 ppm
detergent ppm/zinc ppm ratio = 2.5

6. 5W30 Royal Purple XPR (Extreme Performance Racing) = 74,860 psi
(27.9% below no.1)
zinc = 1421 ppm
total detergent = 3050 ppm
detergent ppm/zinc ppm ratio = 2.1

7. 15W40 Farm Rated Heavy Duty Performance Diesel, CI-4, CH-4, CG-4, CF/SL, SJ (conventional) = 73,176 psi
(29.5% below no.1)
zinc = 1325ppm
total detergent = 1593 ppm
detergent ppm/zinc ppm ratio = 1.2

8. 0W30 Brad Penn, Penn Grade 1 (semi-synthetic) = 71,377 psi
(31.3% below no.1)
zinc = 1621 ppm
total detergent = 2939 ppm
detergent ppm/zinc ppm ratio = 1.8

9. 10W30 Brad Penn, Penn Grade 1 (semi-synthetic) = 71,206 psi
(31.4% below no.1)
zinc = 1557 ppm
total detergent = 3173 ppm
detergent ppm/zinc ppm ratio = 2.0

10. 15W50 Mobil 1, API SN = 70,235 psi
(32.4% below no.1)
zinc = 1133 ppm
total detergent = 1437 ppm
detergent ppm/zinc ppm ratio = 1.3

11. 10W30 Royal Purple HPS (High Performance Street) = 66,211 psi
(36.2% below no.1)
zinc = 1774 ppm
total detergent = 3676 ppm
detergent ppm/zinc ppm ratio = 2.1

12. 10W40 Valvoline 4 Stroke Motorcycle Oil conventional, API SJ = 65,553 psi
(36.9% below no.1)
zinc = 1154 ppm
total detergent = 1999 ppm
detergent ppm/zinc ppm ratio =1.1

13. Royal Purple 10W30 Break-In Oil conventional = 62,931 psi
(39.4% below no.1)
zinc = 1170 ppm
total detergent = 3184 ppm
detergent ppm/zinc ppm ratio = 2.7

From the same chapter this snipet.
And for the detergent discussion , sorry Greg,

And for those folks who want to avoid high levels of detergent in their oils, for fear that an oil with a lot of detergent will not be able to provide adequate wear protection, let’s look at that above as well. The oils ranked 1st and 12th both had low levels of detergent. And the oils ranked 2nd and 13th both had high or relatively high levels of detergent. The rest of the oils were a mixed bag of high and low detergent oils. So, that is proof that detergent levels are a non-issue, and that there are better things to worry about.

So I will standby my suggestion that the Valvoline Dino VR1 oil is one of the best oils for your 928,
its usually available at most FLAPS and less expensive than the SYN versions, and provides better wear characteristics.
NOTE using a change the oil every year cycle most 928s would be hard pressed to see a 5K miles in a year. so the oil would time out.
NOTE thats my experience on the EAST coast, other areas of the nation will have different results due to changing or moderate weather conditions

Thanks guys, notes taken.

Lots of opinions in this thread:
https://rennlist.com/forums/928-foru...e-and-why.html

While that statement is normally good advice, it doesn't really apply to VR-1. It was pretty stupid on their part what they did when they released VR-1 over a decade ago by calling all 3 "racing" oil instead of some other kind of high performance marketing term.

Originally you would find 3 bottles on the shelf
VR-1 Conventional
VR-1 Synthetic
VR-1 Not Street Legal

I don't even see the "Not Street Legal" oil on their website anymore. Back when all 3 were on the market, the bottles were noticeably different.

From 2007:


https://cimg1.ibsrv.net/gimg/rennlis...d60ada4fca.png

Driven DT50 or GP-1.

Am I mistaken in thinking that the testing you refer to is not your own work Mr Merlin.
The conclusion suggests Valvoline VR1 is one of the best for your 928. Yet all the VR1s tested are 10W 30 oils. I am certain that even amongst the most outspoken oil protagonists we have seen on Rennlist over the years none would have recommended a 10W30. Unless for winter use at the poles.

See the link in post #5 Stan didn't copy / paste the whole blog. There are a few 15w50 / 20w50 oils in the test (see below)

From the opening paragraph:
I call BS that their tests apply to every possible type of gasoline engine. Turbo engines (gas not diesel) see motor oils subjected to extremes heat, 400F+ which is significant and not a part of this test.
Ask any mechanic what happens when inferior oils are used in turbocharged engines. Sludge is the answer as those oils are cooked in the turbocharger.

Let's see all the oils re-tested at 400F+

Every 944 / 928 / air-cooled 911 won't last long on 30wt. Some of us (yes myself included) have tried 40wt in stock 928's, oil pressure was not maintained on hot days.
Granted this person is not familiar with our engines at all, reason why such things should be taken with a grain of salt.

They talk a lot about bearing clearances and the proper oil to maintain pressure. They kinda leave out the rest of the engine that also needs sufficient pressure after the bearings. A couple of us who tried 40wt not only saw low pressure on the gauge but also lifter ticking, which ruled out the gauge being wrong. The bearing were probably still receiving sufficient oil flow as the lifters were starved.

That blog talks about foaming, but doesn't bother to come up with any way to test it.

This is one of many threads discussing and questioning their whole methodology:
https://bobistheoilguy.com/forums/th...t-blog.280231/


For entertainment purposes, here Are the 15w50 & 20w50 oils from that test (and how they ranked):

81. 20W50 Valvoline VR1 Racing Oil, conventional = 97,677 psi
This oil claims high zinc/phos.
zinc = TBD
phos = TBD
moly = TBD
It was tested Summer 2019. The psi value above, produced by this oil, came from testing it at the normal operating water-cooled engine test temperature of 230*F, which put it in the OUTSTANDING Wear Protection Category. But, this oil is way too thick for most any water-cooled engine. However, it is ideal for air cooled engines, which cannot control their oil temperatures well. And it is popular with air-cooled Harley Davidson Motorcycle Owners. So, for their benefit, I also tested this oil at the much higher test temperature of 275*F.

87. 20W50 Castrol GTX, API SN conventional = 96,514 psi
zinc = 610 ppm
phos = 754 ppm
moly = 94 ppm

131. 20W50 LAT Synthetic Racing Oil, API SM = 87,930 psi
zinc = TBD
phos = TBD
moly = TBD

144. 20W50 Millers Classic Performance Oil, API SJ, conventional = 84,764 psi
zinc = TBD
phos = TBD
moly = TBD
Claims high ZDDP level. It comes from England in 1 Liter bottles, which is slightly more than a quart, and is available in the U.S.

149. 20W50 Royal Purple API SN synthetic = 83,487 psi
zinc = 588 ppm
phos = 697 ppm
moly = 0 ppm
.
.150. 20W50 Kendall GT-1 High Performance with liquid titanium, API SN conventional = 83,365 psi
zinc = 991 ppm
phos = 1253 ppm
moly = 57 ppm
titanium = 84 ppm

166. 20W50 Resolute Racing Oil, API SN conventional = 77,554 psi
zinc = TBD
phos = TBD
moly = TBD
This oil cost only $2.49 per quart when bought for this test. It is a Regional Oil from the Mid-Western U.S. farm country.

206. 15W50 Mobil 1, API SN synthetic = 70,235 psi
zinc = 1,133 ppm
phos = 1,168 ppm
moly = 83 ppm

228. “ZDDPlus” added to Royal Purple 20W50, API SN, synthetic = 63,595 psi
zinc = 2436 ppm (up 1848 ppm)
phos = 2053 ppm (up 1356 ppm)
moly = 2 ppm (up 2 ppm)
The amount of ZDDPlus added to the oil, was the exact amount the manufacturer called for on the bottle. And the resulting psi value here was 24% LOWER than this oil had BEFORE the ZDDPlus was added to it. Most major Oil Companies say to NEVER add anything to their oils, because adding anything will upset the carefully balanced additive package, and ruin the oil’s chemical composition. And that is precisely what we see here. Adding ZDDPlus SIGNIFICANTLY REDUCED this oil’s wear prevention capability. Just the opposite of what was promised.

249. 15W50 Joe Gibbs Driven BR Break-In oil, conventional = 51,299 psi
NOTE: Total Seal also sells this Break-In Oil with their label on it.
zinc = TBD, but high levels are claimed on the bottle.
phos = TBD
moly = TBD

My shop use standard 10 W 40 on my car and after changing to 5 W 50 VR1 oil consumption drop significant.
Here we have mild summers with 75 F on good days, very hot days are 90 F.

Driving the engine warm is usually a trip from 7 to 10 miles. Than my oil pressure falls to 2-3 bar at idling.

I think good anti foaming formulas are essential for low oil consumption in our engines. The car is often on autobahn.

This oil isn´t a mobil 1 0 W 50 and for my task it works perfect. Stop and go is rare here and I´m not in the south.

FWIW I ran out of time on reading that whole article and posted the testing of the 30wt oil, halfway down the page.
and, doing some spitball figuring that the 50 wt oil will be close in performance to what the 30 wt is.

NOTE I am not suggesting to use 30 wt in a 928
only the 20 W 50.

In essence any name brand oil and proper wt. will do a fine job of protecting the metal inside your engine,
if its changed at reasonable distances and the engine is not overheated.

In general, this is true, but some oils clearly do a better job than others. For example, here's a few UOA entries from my supercharged 79 where I first used Shell Rotella Dino oil, had terrible metal wear numbers and then switched to Driven DT50 and the numbers improved every oil change after.

https://cimg5.ibsrv.net/gimg/rennlis...aba00c8ef0.png