Hello, for a 944 atmospheric, what is the best oil 20w50,15w40,10w40? I use 20w50 but there is always a lot of oil pressure when cold, 5 bar, and when hot, 3.5 bar. Thank you

 

That's how it should be, stick to it.
In case you use the car in very cold conditions, you could switch to 5w50 for easier startup.

 

Is the correct one 20w50?

 

That'd be the thickest, so most horsepower-robbing. Thick oil can actually cause more wear also (the engine being harder to turn). And too thick for some temperatures.
5w40 is good IMO for most normal circumstances. What is the temperature range where the car is run? Track usage or just street?

 

En la calle, temperatura 28°c

And 10w50??

 

Up

 

This is normal
https://www.clarks-garage.com/shop-manual/lube-03.htm

FWIW I use 20W-50 (Valvoline VR1) but only take the car out in warmer temps above 30F. The owners manual has recommended oil viscosities for specific ambient temperatures (pdf can be googled) - it says 20W-50 is good to about 15F IIRC.

 

Would a 10w40 be better? Here we are in Spain at 20C°

 

IMO, yes. Running thicker oil just adds drag unless you need it for racing or very hot climate. Drag robs power, causes wear, reduces MPG.

 

Driven DT 50 Synthetic 15w50 for aircooled engines.
Knocks engine oil temps down significantly.

 

These videos might help you make your decision.

 

Could you tell me some European brand of 10w50 car oil, thank you

 

RAVENOL RSE SAE 10W-50
RAVENOL HVE High Viscosity Ester Oil SAE 10W-50
https://www.ravenol.de/en

 

I don't understand what the videos say!!!

 

Repsol Leader 10w40 A3/B4 SemiSynth 5L
Repsol Leader 10w40 is a multigrade oil that combines synthetic components with very high quality minerals for use in passenger car engines and light commercial vehicles.

This Repsol 10w40 combines high resistance to oxidation to optimize the change period, and a viscosity that facilitates the start of the vehicle, reducing wear.

Repsol, a leader in oils and lubricants, uses all its experience to design this Repsol Leader 10w40 and ensure superior efficiency in engines where it is necessary to use a 10w40 viscosity with A3/B4 specifications

SPECS:

ACEA A3/B4
API SL/CF
MB 229.1
VW505.01 / 505.00
Reference RPP0104MFBSEMI
€23.89
Tax included
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