Macster

We're not sparring. Just having a friendly exchange of ideas. I think I can tolerate quite well disagreement and differences of opinion.

If Porsche started recommending 5w-30 or even 5w-20 oils I'd agree the greenies have gotten to Porsche. But a recommendation to use a multi-grade synthetic oil like Mobil 1 0w-40 oil is not a capitulation to the greenies.

Primarily what drives an engine's oil viscosity requirements is its bearing clearances and piston/cylinder fits along with the open valve spring pressure (which can result in extremely high pressures at the cam lobe lifter face interface -- a open valve spring pressure of say 170lbs given the very very narrow contact line of the lobe against the lifter face can result in 170,000psi of pressure there which of course the oil must help deal with) .

An engine targeted for production vehicles is generally a "tight" engine -- built to have tighter clearances -- to deliver good compression (helps drivability at part throttle (<30%) where most street car engines spend most of their time), deliver good fuel mileage, reasonable oil consumption, and quiet operation. A downside -- minor imho -- is this engine takes more miles, more running time, to make max power. IOWs, break in takes more time though one can speed this process up by following a more agressive break in regimen. I believe this is ill-advised but to each his own.

While a thicker oil appears to be a no-brainer choice for better oiling this is not necessarily the case. A heavy oil will run hotter due to hydraulic friction. A heavier oil may actually result in less ideal lubrication not better.

I have no real interest in what oil is used in high performance race track oriented cars in Dubai. Especially ones backed by Porsche factory money. Winning is everything and as long as the engine lasts the race who cares about the other considerations.

However you might be surprised as to what oil is used. Race engines are a different breed. My neighbor builds race engines and his engines are built to use a special 0W racing oil for as little friction as possible. In the racing application these engines are used all that matters is the engine produce max. power for as long as the race lasts.

I'm always leery of advising anyone to step outside of the automaker's recommended oils. I'm not prepared to back my recommenation by any guarantee. Thus I advise any Porsche owner to go with the manufacturer's recommendations regarding oil type, viscosity based on the prevaling ambient temperature in the area the car is driven. I will advise a more frequent oil/filter service interval however.

Sincerely,

Macster.

white99c2

I went for a ride just a bit ago without the AC on, the dash showed 100F outside temperature. I drove south on Scottsdale road for 12 miles, I hit many lights and my climate control display for the coolant never exceeded 92C with the radiator fans on HIGH, I have a switch installed.

I jumped on the 101 expressway and drive 75 MPH for about 10 minutes and the temp dropped to 91C, thats 195.8F with the fans blasting on high. I got off an exit switched back and headed north to the Scottsdale Road exit again, the temp fluctuated a degree or 2 up and down. When I got off at Scottsdale Road again it was 94C, thats 201.2F. I'm 50 miles into this test ride now.

I pulled over when I got off and let it idle for 3 minutes, the temp went up 99C thats 210.2F. I drove north on Scottsdale Road for 5 miles and it went back down to 95C thats 203F. I AM BAKING HOT NOW, the outside temp is 103F on my dash thermometer and I have no A/C on.

I shut the windows and turn on the A/C to 75 degrees, center vent and recirculate.

On the last 7 miles of the trip I hit 3 lights and when I was in front of my house the coolant temp was 106C, thats 222.8.
I don't think that anything is wrong with the car. I think the condenser is heating up the radiator when the A/C is on.
Now before you chime in here and ask questions that have been answered, read the post!!!!

chsu74

Try replacing your cabin filter. It may be clogged and working your AC too hard. Same thing was happening to my AC at the house. Filter was not cleaned in 2 years and AC was crapping out in 100 degree heat during the afternoons. Cleaned it and now works like it should..

white99c2

How do I get to it?

2K7TTMIA

open the frunk, the black plastic cover on the passenger side. look under the wiper cowl, it should be lying flat with a foam deflector covering part of it. takes about a couple minutes to do.

jrgordonsenior

Just heard from Dubai, they run straight weights only in their Porsches over there either 40 or 50.....