356 and winter oil

[Johnny Graham]

Hello, what lovely weather we are having..the roads are dry and dusty and the sun is shining..well, in Fife anyway.

And so its 356 time, but I worry about the 20w50 oil on these winter mornings. Not only that, but my car has always taken ages to warm up, and now with an external oil filter its even worse. A 30 minute work out a few days ago saw the temperature just at the top of the green, eventually that is, and thats with my infamous cover over the grille! That point on the dash guage is equivalent to about 180 degrees on my dipstick guage.

So, I am wondering whether it is time for 5 or 10w40, until the weather warms up, to give my engine a bit of an easier life on cold mornings, and I also understand that thinner oil might run a little hotter?

Trouble is, there arent many miles on the Valvoline racing 20w50 in the sump, and I cant see me using the car more than once a fortnight or more.
So it seems a bit of a waste, cant decide if its worth it. Wondering about faffing about keeping the drained oil in a clean container etc. What would you do? .. and any recommendations for oils in the thinner range?

Ta!

[Helen]

don't know we've always stuck with the 20x50 in the 356c what ever the weather. although last winter wasn't as cold. and i live alot further south than you.


I'd ask Mike or Paul smith of PR services.

[Johnny Graham]

Yep it was Mike who advised me about the VR 20w50. I was wondering if there was something about the 356 engine that meant it was happier with the thick stuff all year round..
It does get a touch parky round here, though..

[roy mawbey]

The oil viscosity thing is interesting to me. When I first started driving 356's in the sixties using multigrade oils was strickly a "no-no" from Porsche. They reckoned then there was a good chance the oil would not perform well. even in the early 70's it was still not used.

I was told to use a good HD oil like "Shell Rotella S30" which I did for many years until they changed the spec name. To my knowledge, SAE 30 grade was the recommended lubricant for all temperatures. I am sure someone will let me know if I am wrong on that?

I do use now a multigrade 20/50 and often wonder if I should have continued with a single 30 grade oil. In my car also even down here in the South the needle on the gauge never gets half way in very cold weather on a 1/2 hour run on normal roads.

I don't think I would go lower than 20 on the grade and I don't see covering the back grill as being the correct thing to do? ( I worried a little even putting a metal Porsche club badge on it 30 odd years ago ) But then again I do get a bit paranoid sometimes!

Roy

Roy

[40 scout]

Hi Johnny

My temp guage rarely climbs out of the green - I did 250 miles last Friday and it didn't really get into the middle section.

I've got one of those lovely new ali oil coolers and think it's doing it's job, or the guage is maybe a little off.

Oil wise I go for a cheap(er) 20. 50 Millers (can't remember which) I bought 5 gallons and go for the 'lots of oil changes' method.

As it's quick I tend to change it before 2000 miles.

It works for me anyway!

Glad you using your car - mine gets out every week too.

Steve

[Johnny Graham]

Great, so lots of folks use 20/50 year round, and I'm not the only one who's car runs cool..
I need a couple of parts so will be speaking to PRS soon, so will ask the boys..although last time I called for parts a FEMALE dealt with my order, of all things. What is the world coming to...

[oilman]

You could try a 15w-50 or 10w-50 to make it a bit friendlier on start up if your using over winter.

When hot 20w-50, 15w-50 and 10w-50 are all the same at SAE50.

Cheers

Guy

[Johnny Graham]

Thanks Oilman! Goes back to the same question then, why dont we all run 10W50 all the time, and why do PRS always recommend 20W50?

[Helen]

i always presumed that if the oil is a bit thicker than it won't leak out as easily.

[oilman]

Unless the gaps it's leaking from are very large, oil is so thick when it's cold that the viscosity, from 10w to 20w, doesn't make too much difference. And if the gaps are that large even though the engine metal expands when hot, the oil will be lost at a very high rate when the oil is hot and thin.

A lot of the time, people use a 20w-50 out of habit or 'tradition'. Manufacturers often label 20w-50 oils as for classics, which just adds to people believing that a 20w is necessary.

Another thing that affects it is the viscosity range of mineral oils. Most older cars need a 50 as they have larger engine tolerances than modern cars, but mineral oils can only span a certain size viscosity gap. So you can't make a stable 10w-50 mineral oil and as the 50 was the important part to the car, the cars used a 20w-50. Since those sorts of oils were first used, good synthetics have come along and stable 10w-50's are acheivable, so your car can get the best cold start protection available.

[Johnny Graham]

Ahh, so that means I could go 10W50 but it would mean I would have to change to synthetic..('pop', another can of worms pops open).

I'm not too bothered about oil leaks, but I am a 964 driver. I'm constantly slightly oily..

Just off the phone to PRS, and Paul is going to chime in, when he gets a minute to get his hands out of those 'boxes.

[Paul @ P R Services]

We recommend Valvolene 20/50 because it has more Zinc (ZDP) that most oils - you need that, to help lubricate the cam, particularly the High Point Loadings on the tips
The cams in `Our Cars` run two Cam Followers on the same Cam Lobe, so twice the wear of most engines

In Addition :-
1) - that is what we race with
2) - that is the one we have put into every 356`s for the past 20 years
3) - that is the one that has never given us a problem
4) - it is not overpriced.

[Helen]

IMHO. when someone whos been working with these car since he was knee high to a 356 bumper gives you advice.....you listen.