mickster

Very nice!

Everyone has opinions on oil (and huge flame wars here). In the end it is brand vs. synthetic vs. conventional.

Personally, for high mile engines that heat up like a Porsche, I prefer Mobil 1 Synthetic because it is uniform in nature and resists thermal viscosity breakdown. No idea what was in before but in 3 years sitting it was very, very clean with the last change about 1000 miles ago.

With the New York weather getting to Phoenix temperatures, I think it's a good choice.

The down side is synthetic oils and lubricants in general have a higher chance of seeping through older gaskets if you switch over to them.

Drewster67

Valvoline 20W50 Racing oil .....

Valvoline Conventional Racing Oil is designed for racing applications only. Its unique formulation contains premium mineral base stocks and advanced additive technology to reduce internal friction and help enhance horsepower output. NOT to be confused with Valvoline VR1 which IS street legal due to it's reduced amount of ZDDP.


•Features Include:

•Designed for high-performance racing engines
•Proven to provide more horsepower than the most widely used oils in grassroots racing
•Helps increase horsepower through advanced friction modifiers balanced with reduced detergent levels
•Contains increased amounts of ZINC and PHOSPHORUS (ZDDP) for extra engine protection. (needed for flat tappet cams!)
•This is the oil that we put in Our Personal Race Cars & Hot Rods here at Spencer's Speed & Cycle.
•Recommended for Hot Rods, Muscle Cars, Imports, Motor Cycles, Marine, Diesel, or any Heavy Duty application.
Not for use with motorcycles with wet clutch setups.

NOTE: People often ask us why this oil says "NOT STREET LEGAL" on the bottle? The second most asked question is what is the deal with ZDDP?

Both of these questions go hand in hand. ZDDP is an extreme pressure/ anti wear additive. It has been an additive in motor oil for a long time. The A.P.I. has phased out ZDDP over the past few years due to the fact that it can ruin catalytic converters on extremely high mileage vehicles with alot of blow-by. It is also being phased out of Diesel oils such as Rotella as diesels now have filters in their exhaust systems. The A.P.I.(American Petroleum Institute) rates oils ands puts the rating on the back of the package. This oil has no such rating so is therefore not street legal. If you have a late model vehicle with high mileage, we recommend Royal Purple.

BIG 928

i use the 20/50 valvoline vr1 racing oil also. 2007 to date in my old gts race car brilliant stuff. the engine has been that reliable so far! the modern oils are to thin

regards mark

longleader

M1 15w/50, no problems in the Florida heat. My 83' shows 2.5 to 3 bars pressur at idle with the AC on.

NoVector

I switched from Mobile 1 to royal purple 20/50 and I swear I burn less oil and have less “clouds” on deceleration. BUT, the BX had a 4th of July sale yesterday with Mobile 1 at $1.89 a quart. I now have 2 cases in the basement…

GlenL

Amsoil 15w50 racing

LT Texan

20w/50 Castrol Syntec for classic cars.

Now, name changed and 5w/50.

Extra zinc.

antlee928

There has been much discussed, talked about and argued about oils used/recommended for the 928. Given their flat tappet head design and also recognising this is a last century designed engine and designed to be run on last century oils, IMHO one should stick the the owners manual recommendations. In my part of the world and based on the temperature variations I see I use a 20W50. MOST IMPORTANTLY, and because of the engine design (flat tappets), you should ONLY use an oil that has at least 1000ppm ZDDP. Often racing specific oils offer such levels (and more) but tend not to meet any local.legsilative requirements for road use. Personally, I use Valvoline MaxLife 20W50 which (last time I looked) offers about 1100ppm ZDDP. Of course their are other brands/types but you should ALWAYS check the ZDDP rating. Most modern oils are developed to meet more stringent eco requirements and are also designed for cars with much tighter engine tolerances and also having to meet ECO requirements typically means MUCH lower levels of ZDDP. Much below 1000ppm is a recipe for higher engine wear.

Suggest you do a search on this forum regarding oils and zinc levels. You can also check the Landsharkoz site in Australia, http://www.landsharkoz.com/index.htm.

Hopes this helps

Cheers

kelanel

another for valvoline vr1 20w-50

mirousse

I searched advices at the long time established local Porsche dealership and they recommended Castrol 20W50. Castrol it is for me. Car is a daily driver 6 months/yr, stored for the other half and the engine interior looks just like Bilal.

Michel 89 S4

robot808

Would somebody please check on MK? This was posted hours ago. I just want to know that he is OK.

928 at last

Brad Penn 20/50 race "The Green Oil" it's got the ZDDP that's needed.

s4bill

If you go to the Mobil 1 webiste and select What oil is right for my car, it recommends 10W 40

Current Vehicle:
Year: 1989
Make: Porsche
Model: 928
Engine Type: 8cyl. 5.0Liter Naturally Aspirated


Mobil 1 0W-40
Mobil 1 0W-40 is an advanced full synthetic motor oil that helps extend engine life by reducing engine wear and oil breakdown. Mobil 1 0W-40 provides outstanding performance under all operating conditions and meets or exceeds the warranty requirements of many leading car builders.

s4bill

If I am reading this chart correctly, Mobil 1 15w 50 has 1200 or 1300 ZDDP?

http://www.mobiloil.com/USA-English/...duct_Guide.pdf

Bjbpe

In the aerospace world where the engines are subjected to incredible stress, we would only use "type 2" which is a synthetic very similar to Mobil 1. I use 15-50 on my S4 here in Wyoming. Obviously it doesn't get that warm around here. I don't doubt that the high viscosity does drag the engine a bit but I don't drive that hard anyway. I want to protect my engine over high efficienct. Not much question in my mind that Mobil 1 would be great.