Paulyy

Me, my dad and my uncle where talking about oil for my car. he was recommending i should use CASTROL EDGE SPORT 0W-40 which is full synthetic oil which is Porsche A40 approved.

I know our engines require a higher level of ZDDP.

What i don't know is what A40 is.

Should this be fine for my engine?


I have done a search for what i was looking for and nothing came up. But did find things in the 996 forum but they're different engines then our 944 engines.

Can anyone help me out on this?

Cheers!

333pg333

Arghhh....Paulyy, what have you done....

lol.


Even in Melbourne weather you can use a 20w/50 just as the owner's manual suggests. Do you have your manual? Check it out.

Paulyy

LOL... nothing.

Unfortunately i dont have the owners manual. But i've seen the oil recommendation picture graph.
We'll it's soon for me to do a service (oil/filters/plugs)

You know when you do the searches on the sites for oil recommendations, it gives you a list of oils. what i think it does (because i searched for 993 & 996 911 turbo and came up with the same stuff) it searches everything that is 'Porsche A40 approved' and says this is what you use, regardless of what year/type of car it is.

and no where it tells me if theres any ZDDP content which is what porsche recommends for the older engines. even my dad knows this because of the 924 he owns.

I just want to know what porsche A40 approved means, what additives ect. if it's right for our cars or just the newer ones.

The oil i've got now is 15w60 with ZINC PP: 1110 (what ever that means) i'm going to do a search for that to understand it.

gruhsy

0W-40 is pretty light. I've used 0w30 on diesel motors in the winter on heavy equipment and turbo charged diesels........... it's pretty warm in Aus compared to Can
I checked out Castrols web site

http://www.castrol.com/castrol/secti...tentId=7049418

I'm thinking it's for modern porsche engines not ours.

just my thoughts

Jason

Tom M'Guinn

I recently switched from 20w-50 dino oil to 10w-40 dino oil (for the winter anyway) and have to say the lifters are noticeably quieter while the motor is warming up. Just say'n...

EVOMMM

yes both porsche and mobil say this the oil we need if you live in a climate thast does not exceed 90 degree

333pg333

Paulyy

it does sound like it's for the newer cars. They shouldn't miss lead customers with the wrong info

I'm probably going to try the Penrite racing series oil. it has more zinc PP from 1110(what i've got) to 1240-1320 on the lighter oils.

probably go 10w-40 or 15w50

JET951

Hi Pauly ,the oil viscosity chart within the owners manual printed by Porsche that came with you're 951 , or any other Porsche from last century for that matter you will see the shaded "Look at Me"( centre) section in regards to multi grade oils ,the first one in this section is }

From minus 10 deg celcius to Unlimited High ambient temps = 20w-50 oil viscosity ( not 0w-40 )

Interestingly( from memory) the pre 1982 Porsche owners manuals placed 20w-50 at minus 15 deg cel to unlimited high ambient temps

This was printed by Porsche in the owners manual for a very good reasons }

Reason 1) the single cam 944 all alloy engine was designed in the late 1970's , this 8 valve engine was sold to the public as the 1982 year type 944 ,this is important to remember because in regards to engine oil viscosities available world wide, the new kid on the block ( so to speak ) in the 1970's was the 20w-50 oil viscosity which was by the late 1970's was available world wide as opposed to using a mono grade oil ( example SAE 40 ) which is just a straight 40 grade from the 1960's & early 1970's.

So like the 928 engine( same era) the water cooled 944 engine was designed with an oiling system ( read large dia oil galleries) to work perfectly with oils like a 20w-50, in fact much larger in dia compared to oil galleries in this century Porsche engines like say the 996 / 997 / 986 / etc etc which are designed around thin oil viscosities like 0w-40 .
Note the 0w-40 oil vis did not become available to the public until this century , not last century .

2) Now lets go to oil pressure and the 944 / 951 engine , first of all some basic info }

Note A } High Core Temp = operational oil temp within the engine on a warm day , not the water temp in the radiator etc

Note B } The below oil pressure readings were done with a workshop ( screw in ) oil pressure gauge on multiple 944 & 951 models over two decades , the reason is because there is too much variation of the in car oil pressure gauge ( its only an aprox reading + old wiring only makes it a bit worse)

The engine oil pressure relief valve opens around 8 bar pressure = aprox 116 psi , now the oil pressure gauge within you're dash instruments cluster only reads up to 5 bar , this is important because people often are confused with the oil pressure gauge needle pegged at "MAX " of 5 bar until the core temp gets hot enough to show maybe 4.5 bar + at mid range RPM , now this is the case if one uses a 20w-50 engine oil

Interesting note } the humble 924 & 931 had an oil pressure gauge in the centre console that read 0 to 10 bar oil pressure ( all cars should have this )

Now we go to the same engine( 944 / 951) , same day( 25 - 30 deg cel day) & we install a 0w-40 engine oil , one will notice very quickly that the oil pressure indicated will be noticeably lower at all temps , meaning much much lower oil pressure , in fact so low that when you get her up to high core temp , the oil pressure warning "RED" light will be glowing at idle , at this point when you rev the engine out you will see no more than 2.5 - 2.7 bar max pressure , thats over three times lower oil pressure than the engine could produce theoretically , I know we do not need 8 bar hot , but you see what I mean as how low the pressure is

3) The 944 / 951 / 944s / 944S2 / 968 engines can & do suffer from No 2 conrod bearing failures , here in Aus we call it big end failures .

Question } How can I increase the risk of a 951 conrod bearing failure on no 2 ?

Answer = easy , run a much thinner oil viscosity( say 0w-40) as opposed to the owners manual that came with the Porsche from last century and at high revs & load = BANG = $$$$$$$$$$$$$$$$$$$$$$$$$$


Question } How do I decrease the risk of No 2 conrod bearing ?

Answer = Follow the instructions printed by Porsche in the owners manual & always stay on as higher vis as possible in regards to ambient temp .

4) 944 / 944s / 944S2 / 951 / 968 can & do suffer from cam lobe wear ,Twin can chain sprocket wear, lifter face wear ,valve guide wear, piston to cylinder wear & crank thrust bearing wear if the "Oil Film Strength" is too low

Note C) Oil Film Strength = the ability to keep two metal parts away from each other that have no oil pressure between them apart , just like the parts listed above

There are ONLY two ways on this planet in increasing oil film strength in regards to engine oils sold to the public }

1) Increase oil viscosity from say a 0w-40 ( example) to a 20w-50 , if these two oil samples have the same levels of ZDDP ( which they normally do not ) then just the oil viscosity will give higher oil film strength , meaning the 20w-50 will have higher oil film strength

2) Increase ZDDP levels , keeping in mind all compliant oils in this century for this century cars have to comply with very strict ACEA Emission protocols , and generally speaking the lower the viscosity the later in this century the engine oil will be designed for these later designed engines

Plus , most if not all 20w-50 engine oils are for last century cars( like the Porsche 944 series) , so these oils are allowed to have decent levels of ZDDP

The upshot is , more viscosity ( as per owners manual ) & more ZDDP( up to a limit) = very high oil film strength

5) 944 / 951 / 944s / 944S2 / 968 going to the track for some fun with " R" spec tyres

Tips }
A) never go to the track if the conrod bearings life/ age is unknown or if it has been on lower vis oils in past , sump off & replace

B) Twin cam engines , same as above + replace the timing chain ( between cams) and their nylon slippers

C) 944 / 944S2 etc here in Aus , use only 25w-60 racing oil
951 here in Aus use 25w-60 racing oil ( Minium Viscosity )
Note } racing oils are except from the ACEA protocols & are allowed to have high levels of ZDDP + they do not foam as much as street oils so aeration is improved ( VERY IMPORTANT )

D) A bit more serious at the track
944S2 / 968 / 951 here in Aus , always fit a much larger oil cooler ( three times bigger)
Improve the crankcase breather system , this is extremely important
New conrods ( good quality afermarket ) not 26 year old standards

E) Seans 951 3.0L twin cam ( see avatar on left) chases down this century 996 & 997 GT3's on the track with racing slicks and does not use any form of dry sump or acusump system , standard sump & baffle but big oil cooler & improved crankcase ventilation system , however after seeing others using less than 25w-60 racing oils & their engines exploding ,I know full well if we even used 15w-50 street oil at the track I would not hold out much faith at all of even finishing two laps without an expensive failure , hence the reason for me saying the 951 at the track must use at least 25w-60

I could go on but ran out of time

Bruce Buchanan
Buchanan Automotive

333pg333

Thanks Bruce.

Paulyy

Wow, Thanks Bruce!

EVOMMM

but what about the cold start damage caused by heavier weight oil before it reaches operating temp and also cars that are not raced before anyone bangs thier head again i am looking for as much info to keep my car as long as possible as i am not a racer

333pg333

If there was all this cold start damage why aren't there hundreds, make that thousands of our cars with broken down motors due to all this supposed cold start damage?

Sure, if you are in a deep New York Winter there's no harm in going down in oil viscosity.

The head banging wasn't specifically directed at you, more at Mobil and Porsche US that proffer this blanket far reaching statement that we should all be using M1 0w/30 or 10w/40 on all Porsches. Remember that neither company cares a fig about our cars. I bet they'd rather all front engine P-cars to suddenly disappear off the face of the earth. They view us as a Yokel cousin that you begrudgingly invite to the wedding.

JET951

Hi NYPOWR4 , what's interesting is that Sean's 3.0L twin cam 16V turbo 951 is first & foremost a every day drive car( its a commuter street car) that drives to work six days a week , full steel panels , full insulation , full carpets ( full weight ) , excellent A/C with upgraded parallel flow condenser, 4 speaker stereo , electric aerial , electric sunroof & has two surfboards in the back seven or eight months a year & only competes at the track ( to knock off GT3's for fun ) , this car is the perfect example of what a functional sports car should be , meaning drive to the track on Sunday & drive it home & then drive to work , it doesn't get any better than this. ( great fun ).
Plus great fuel economy if driven to work with little or no boost ( not easy I know , you have to have will power there , because this car is way too much fun to drive )

Now some oil viscosities that are OK for the 944 / 944S2/951/ 968 that are used year round as a street car only but where the ambient temp rangers are massive .

Say as in you're case the winter temps are quite low for a few months

The below are oil viscosities that are kept as norrow as possible ( trying to keep Vii's as min as possible ), meaning do not fall for the 5w-50 or 0w-50 year round oils for these last century engines

5w-20 oil vis is good up to a MAX ambient temp of minus 10 deg cel ( 14 deg fah)
5w-30 oil vis is good up to a Max ambient temp of Zero deg cel ( 32 deg fah )
5w-40 oil vis is good up to a Max ambient temp of + 10 deg cel ( 50 deg fah )
The above are to used in extreme cold , in summer ( if hot ) then use 15w-50 or 20w-50 , you may be able to get by with just a 15w-50 all year round , but its a compromise with extremes of climate

Remember these are Max ambient temp ranges , also you will probably have to buy a boutique oil brand that has excellent ZDDP and advertised as such ( not compliant ACEA emission oil for this century cars), but comply to last century ACEA protocols that are pertinent to you're last century Porsche

Note } Vii's = viscosity index improver's , these are additives that try to change the way the oil behaves between cold & hot ( they are not lubricants in their own right ) , basically Vii modifiers are molecules that are sensitive to temp & are among the first things to turn to **** if the oil is left in the engine for too long ( all multi grade oils have them ) its just a bit better to not have too much of this .

Its interesting to know that if you have say a 10w-40 engine oil ( example only ), they start with a base stock of SAE 10 ( No SAE 40 is used at all )and then just keep adding Vii's until the approx 10w-40 is achieved , same goes for all multi grade oils , so the bigger the spread in numbers the more Vii's are used

Whats also very interesting is oil pressure ( high core temp , oil temp 95 deg cel ) at idle on say a 951 with a 5w-50 engine oil , then repeat the test with a 20w-50 engine oil ( same day same car same ambient temp same oil temp same workshop oil pressure gauge )
Results = the 20w-50 gives higher oil pressure at idle & right through the rev range , in fact we did this test on a customers 951 ( hot summers day ) because his oil pressure oil warning light was flickering on at idle in heavy traffic on a 5w-50 engine oil , on a 20w-50 engine oil the oil warning light never came on again , funny that , it says so in the owners manual

Another interesting thing about oil viscosity numbers on the oil bottles you buy , when you see a 5w-50 ( example only) , you would think it has the same oil viscosity as a 20w-50 when hot , well it plainly doesn't( see above) , nor does it have to , its just an aprox number , for example it may well be closer to a 7.5w- 45 viscosity when the oil is new or near new but will change with the age of the oil ( heat cycles )

EVOMMM

thanks for all the info im only looking to be better informed there is so much bull**** out there im totally confused the same goes for my 1988 M3 on that list same **** so i just want the best for my cars i hope you all understand i feel better thanks again great info
Mike