FYI Motor Oil 20W-50, NFG & not factory approved, see page 111 of Owner Manual

[JD159]

Originally Posted by 911tracker85

JD
I was a math major and my room mate was a philosophy major. when he was taking a 'logic' class and get stuck on an argument, I would convert the various phrases to symbols and then turned the whole think into a symbolic logic equation to solve.

Sounds more like a "critical thinking" course. All of mine revolved around this


Takes the fun out of arguments with most people though once you understand it...

As for oil, running 10w40 amsoil. Will be increasing to 20w50 z rod for the added zinc. Flash I noticed you still run the 10w40. I get more valve train noise with the 10w40 after a few thousand miles. Seems to break down and lose viscosity too quick. I figure the 20w50 will maintain its weight as it breaks down relative to the 10w40.

[flash968]

the end of that article is the key. as long as the oil smells good and is clear, it's good. once it turns dark, it's done. the problem with dino oil is that it turns dark very quickly, especially on a higher mileage engine, due to carbon build up. further, the polymers in dino oil do not react as well and expand as far as those in synthetic oil, especially when the oil is dirty. so, while you may think you have a 20/50 oil in there on your 100k mile 944, you likely have more like a 20/30 after the first 1500 miles following a change, whereas the synthetic oil will maintain its ability to reach the higher viscosity.

if you change your oil frequently enough, you can run just about anything, as long as it can handle the heat range of operation. if you only street your car, you can get away with a much lower viscosity oil than if you track it. the lower the viscosity, the easier to start, the more quickly it gets up to temp, and the less resistance on the moving parts, making the engine rev more freely, thereby increasing fuel economy.

it is a huge mistake to run a 20/50 oil on a pure street car. there is no reason for it. the oil temps will never get up high enough to need it. all it is going to do is make the engine work harder, run hotter, and get poorer fuel economy. i used to run by the old "if it's thick it's good and if it's thicker it's better" philosophy. however, when i switched from a 20/50 to a 10/40 i immediately noticed that the engine revved more freely, and my operating temps DROPPED. my oil temp went down a full 5 degrees. i then switched from redline to amsoil which had a higher upper end limit, and i was good to go, with all the protection i needed, with none of the drawbacks of the heavier oil

[princej]

Originally Posted by flash968

it is a huge mistake to run a 20/50 oil on a pure street car. there is no reason for it. the oil temps will never get up high enough to need it. all it is going to do is make the engine work harder, run hotter, and get poorer fuel economy. i used to run by the old "if it's thick it's good and if it's thicker it's better" philosophy. however, when i switched from a 20/50 to a 10/40 i immediately noticed that the engine revved more freely, and my operating temps DROPPED. my oil temp went down a full 5 degrees. i then switched from redline to amsoil which had a higher upper end limit, and i was good to go, with all the protection i needed, with none of the drawbacks of the heavier oil

hi, what is the general consensus on that statement about a pure street car, like mine not needing 20w50. as I have been using it for years?

vr1 racing oil 20w50 for a pure street car. is it unnecessary?

Car is an ex race car , 1987 944. at warm up oil pressure is 3.5 - 4.5

Im just curious what everyone in the community says. as I have never heard this.

[CHICKS]

Originally Posted by flash968

as long as the oil smells good and is clear, it's good. once it turns dark, it's done.

That is complete bull *****. I assume you've NEVER had an oil analysis?

Man, seriously, 99.9% of the stuff out of your mouth is bull *****.

[cockerpunk]

Originally Posted by flash968

the end of that article is the key. as long as the oil smells good and is clear, it's good. once it turns dark, it's done.

we were off to such a good start, but this is total BS.

color of the oil is no indication of it is lubricating properly or not.

[JD159]

I'm indifferent about the 20w50 not being necessary for a street car. Like I said, I get more lifter noise in hot weather with a 10/40. My personal opinion is 20w50 in warm and hot, and 10/40 in COLD. Not spring or fall cold, but below 10 cold and into the negatives.

However, I do believe that a vr1 racing oil, although I can't recall what kind of additive pack it has, does not have good properties for street use. For example, look at the swepco 502 additive pack and. An amsoil zrod. They have detergents and anti corrosion inhibitors necessary in a street driven car.

Vr1 is a great track oil though from the research I have done.

[JD159]

Just to add, I think what flash is referring to is the condition of an oil that is known to have good lubricating properties for the application. So a 10/40 or 20/50 amsoil redline RP brad penn, so long as it is clear and not smelly and dark, its good.

[princej]

My car is driven only sparingly in the hot summer months, and stored for about 6 months during the winter.

if anyone can clear up the oil debate and tell me which oil is best for a street car driven in hot Montreal summer's, it would be very much appreciated.

as i thought I was being smart by using valvoline vr1.

[JD159]

The oil debate can never be absolutely cleared up. As flash mentioned asserting absolutes in an oil debate is not the right approach.

My opinion is that amsoil zrod 20w50, with high zinc (flat tappets), anti corrosion (for the winters in storage), detergent package (for street cars), and the necessary viscosity for hot mtl summers (I'm in hamilton, but am on route to Ottawa and mtl as we speak) would be a great oil for your car.

Check out the amsoil website for more info!

[flash968]

chicks - actually i send my oil to blackstone every other change.

as i said, i was quoting that article, and happen to agree with it, for all intents and purposes. i can't help that you disagree.

again, on a street car, what oil you choose to run is less important than it being clean. you will never see the temp limits of any oil on the street. it really comes down to how often you want to change it. running a multi-viscosity dino oil requires more frequent changes in order to maintain the upper range of viscosity. it works just about as well, when it's clean. synthetic oil will work well longer, thereby allowing less frequent changes (on average 3 times less under the best conditions). so, unless your dino oil is less than 1/3 the cost of the synthetic, it is cheaper to use synthetic, if only by the cost of filters and rags.

as for viscosity, on the street, there is absolutely no benefit to running a 20/50 over a 10/40, and it in fact will likely cause higher operating temps, cost you fuel, and provide less protection during startup. if you track the car, you may need the extra temp protection of a 20/50.

like i said, i used to be a bit of a dinosaur myself when it came to oils (what can i say? i'm old). it wasn't until i had a long sit down with an oil engineer that i was set straight. as it turned out, he was absolutely correct.

[JD159]

Flash,

Like I mentioned, on hot summer days I get lifter noise in the 16v with 10w40 but less with the 20w50. Thoughts?

[flash968]

lol - tired lifters?

using a heavier oil can quiet tired lifters, but it's like taking an aspirin for a headache, when you really should stop smacking yourself in the head with the hammer.

how's the pressure? if it's less than 1.5 bar at idle, and/or 3 bar at 3k rpm, you could be due for some work.

[JD159]

Brand new lifters. Oil pressure is solid. Put in a bottle of swepco 502 as per Greg Brown and roger at 928rus. Actually seemed to have helped. Cleans out any varnish or sludge on the check valve in the lifter. Thats with 10/40 though. Finishing it off before the zrod 20w50.

[flash968]

the lifters should be quiet (well, as quiet as these can be anyway).

if it's the greg brown down here in anaheim, he knows his stuff, that's for sure.

i am just noticing the valvetrain changes. i wonder if it's not actually the lifters, but rather other valvetrain noise.

[JD159]

Yup, think thats the Greg. Swears by speco 502 for sticky lifters. Its pretty interesting stuff. Will use it for 500 tough and hot miles to get out any gunk.

Strangely, my lifter noise is when the engine is hot, and often on light load and as the rpms come down from 2500rpm. Makes the sound intermittently between 2500 and 1k. Not really at idle tho. It can be a tick or a clack. Not a knock. All guides, springs and lifters inspected measured and replaced. I've had this noise practically since I've owned the car. Fresh oil helps.

[flash968]

well, given how much you have going on in there, it could really be as simple as a tolerance thing, and the thicker oil takes up a gap enough to quiet it down.

you're not going to hurt anything by running 20/50 (except maybe on a really cold morning at startup). it's just not going to give you any benefits on a street car. but with the stuff you have there, i tend to suspect that it's not really a street car (defined as 100% daily driver grocery getter reliable with no issues. not defined as "i drive it on the street").

[VirginiaF1]

Originally Posted by flash968

chicks - actually i send my oil to blackstone every other change.
.

Howdy, do you recall what your test shown after the longest interval?
How many miles OCI and how many more miles did Blackstone say you could've gone?
How many reports have you had done on your Porsche?

Fwiw:
At my 281,000 original engine miles, Rotella 15w-40 keeps her quiet, cool (176F) and revs smooth.
My longest OCI was 6,000 and my TBN was still 6.9 with T6 synth and still 4.6 with T3 dino..
Despite being blacker than coal at night.
Blackstone estimated that 3,500 more miles on my synth and another 1,500 on dino were safely available.
Amazing engines..

Thx!
-mikey

[flash968]

i still change it probably way too frequently (5000 mi). i rebuilt the engine recently, so only have 1 report so far on this engine. i just don't drive the car all that much. i was burning oil before, which is why i started sending it in. it took me a while to figure out what was going on, but ultimately it meant a rebuild.

it's coming up for a change soon, so maybe i'll send it in anyway. the bottle is here and waiting. that's such a cool feature of their service.

the last report is around here somewhere, but showed normal deposits, and nothing to worry about. i don't think they told me how many miles i could go. i can try to dig it up. not sure where i filed it, but i know i filed it.

[9FF]

I guess I'm sitting on the fence on the synthetic/dyno argument because I use a semi-synthetic.

Been using Brad Penn 20-50 and Redline MT-90 since the car was new from the dealer. I keep plenty in stock! Engine oil changes every 10k or yearly and Blackstone analysis every other oil change. Nothing abnormal showing on the tests. This is in FL and on a street car with no track days. I do use a full synthetic in my track cars though.

[princej]

ok, so. to sum up.

Can we agree that Z-ROD 20W-50 by amsoil is better for my street driven car than Valvoline VR1 racing oil 20w50.

or 10w40 Castrol High Mileage oil?

what about brad penn 20w50?