DiegoR

I have yet to see a internal combustion engine with turbo(s) not spit oil in the intercooler/charge pipes.... Some throw more oil than others and in between the same engines as well.

monkeyrs6

Thanks Diego, my twin turbo Audi rs4 likes to spit oil into the intercooler, The problem with the Porsche was the amount it spat in over a short time span. After changing the small filter it seems to have stopped, but still concerned about the oil pressure gauge..Tim

OverBoosted28

Need to clarify which gauge. You have oil level, pressure, and temp. To the immed. left of tach is a gauge that houses the pressure (on right when facing gauge) and temp (left side of gauge. The pressure will fluctuate with revs. More revs= more pressure. Here's mine at about 5k rpm. It should be just about pegged at this speed. At idle it's sits btwn 2-3. Shouldn't drop to bottom. Your thin oil may be the reason the pressure has fluctuations.

monkeyrs6

So as most people guest it was the Small oil filter that was at fault. Not over tight just an inter-mitten fault on a new porsche filter. The techy suggested it might be a good idea to fit the 996 turbo none return valves anybody any thoughts on this ?? i thought it was for smoking cars which mine is not. The 20w50 v-twin oil that everybody swears by is no readerly available in Uk as Mobile brand so what about the mobile 15w50 v-twin or a different brand of 20w 50 ?? Tim

PiB993

Motul 300v 15w-50 is a better choice than the Mobil 15w-50. I might consider running the Motul but is hard to find and very $$$ where I am. It does come in sizes larger than a quart and some people complain about that with Mobil 1 - having to go through 10+ quart containers.

monkeyrs6

So is the mobile 15w59 not just a thiner version of the 20w50 that everybody raves about ??

LexVan

No. 15W50 is not a less viscous version of V-Twin 20W50.

PiB993

There a lot of threads on this. the Mobil 1 20w-50 has one of the highest zddp amounts (slippery oil additives). When first discovered they were used more commonly in automobile oils but then it was found they shorten the catalytic converter lifespan and the oil manufacturers rapidly reduced using the amount of them. Oil synthetics improved in the meantime (as did engine design tolerances?). The Mobil 15w-50 is intended for cars and they reduced the zddp additives in it too eventually. Motul and Mobil 1 V-Twin 20w-50 are for motorcycles (generally speaking with regards to Motul or off road vehicles) that don't have cats and also have the same oil in their viscous clutches. There are some other 'boutique' oil companies out there with large zddp amounts but I think Mobil tends to be the cheapest for this unique type of oil. Also iirc Mobils 20w-50 has more zddp then the Motul I mentioned.

So the problem with the 15w-50 is not that it is thinner when cold. It's the additives they took out a couple years ago - so you may see a lot of threads in the past recommending Mobil's version. Not so much anymore. However, I don't think a 15w-50 would make a car smoke.

I am not sure if or what exactly zddp's connection to wet clutches or air cooled engine design is. I think there have been some threads showing less pitting on cam lobes and related parts with high zddp oils.

I think I mostly got the story right.