The debate on synthetic vs. regular oil to me really boils down to one fact: synthetic remains thinner at low temperature, so on those cold morning starts, synth oil gets pumped sooner and quicker to where it needs to go. Since every automotive person will tell you that virtually all engine wear occurs in the first 30 seconds or so of a cold start, I think that makes the value of synth, well, invaluable, especially for those of us who live in climates where early morning temperatures can be well below freezing for months on end. Once the engine is at operating temp., any good clean oil will do.

 

synthetic oil with their lower shear moments allow any engine to obtain a lower friction horsepower (ie: the hp needed just to keep the rotational mass moving), this translates to higher hp to the wheels. dyno proven. how much? on a wrx, i'd predict a range of 3-10 hp at the wheels.

SUNDANCE: you must be one very busy person, changing your trany and diff fluid every 1,500 miles????? may i recommend you go 15,000 or 30,000 if you drive normally (i am reading the subie maintenance book right now).

 

At what mileage is a good time to start using synthetic oil in a WRX? I heard people saying 8-10K miles is supposedly the right time, but I feel that I am not doing a good job in warming the car up in the mornings so I want to start using synthetic oil as soon as possible.

Thanks,
Igor

 

MarcusWRX, as I stated in my post, it all depends on how you drive, where and how often. Basically my Sube is driven mosly on the weekends and maybe in four months I put on 1,500 miles. The reason for so few miles is I have two other sports compacts. What really suprises me about this thread, is the controversy between mineral oil and synthetic. Over the last thirty years there has been a steady growth in the use of synthetic oils. That in itself means nothing, however; the consistent molecular structure of synthetic oil is clearly superior to mineral oils, with higher heat transfer and less friction to drive the mass, translates into more H.P. at the wheels. And the bottom line is take apart similar engines, one driven on conventional oil and the other on synthetic and thereafter you won't be using conventional oil.

 

Has anyone really thought about this break-in business? I keep reading posts about running "regular" oil in your engine until it "breaks in," and then going to synthetic. What are we talking about here, deliberately inducing a bit of wear in our engine and then, once we've decided that's enough, we go to better oil that will stop the wear? When do we decide how much wear is enough? Is 1000 miles not enough, but 5000 is too much? It just makes no sense to think like that. Engines are designed with certain tolerances between all moving parts and are machined as accurately as possible to achieve those tolerances. That's what blueprinting an engine is all about: correcting the inevitable out-of-tolerance parts that sneak into mass-production. An engine made to spec will run smooth and at designed power for a long time, not after some arbitrary mileage in unpredictable conditions. Furthermore, engines are run in at the factory before they're shipped out; to do otherwise invites warranty headaches.

Having said all that, it's certainly true all new bearings and bearing surfaces have microscopic rough spots that will smooth out only after regular running. I'd rather they smooth out on their own without deliberately trying to wear them out. As Tony the mechanic once said, "There's not much difference between broke-in and broke down."

The message here? Use the best oil always and as soon as possible. For me, that's synthetic.

 

the break in issue is a wives' tale......synthetic oil is good right from the first RPM.

why do you think the Z06, M3, Viper, and a buttload more cars and trucks all come from factory with synthetic oil?

 

From what I've been told from some people who race turbo engines when turbos spool up for long periods of time standard oil tends to breakdown and get very gritty which you can imagine what that does to your engine whereas synthetic turns to ash which just dissolves and does nothing . so take that for what its worth but if anyone would know a race engine mechanic should

 

I remember reading a few years back a study performed by either popular science or popular mechanics on nyc taxi cabs using synthetic vs. conventional oil.

And what is driven more, longer or harder than a NYC taxi cab?

Their conclusion for frequent (3k mile changes) was that there was essentially no difference in lubrication/ protection............

Steve
upstate NY
02 Aspen White WRX
PDE upipe
Bosal downpipe
Tanabe Super racing medallion exhaust
CPU upgrade

 

I remember reading a few years back a study performed by either popular science or popular mechanics on nyc taxi cabs using synthetic vs. conventional oil.

Right, well I'll leave it to you to judge the scientific integrity of either one of those publications. One thing is guaranteed about scientific research: you can always find, or massage, data to support your conclusions. I'm not saying either pop science or pop mechanics had axes to grind, but I'm not sure they were looking in the right places.

NYC taxis lead a hard life, no doubt, but they do have one big advantage: once they start in the morning, they usually don't stop until the end of a shift. And if they do stop, it's for a short enough time that the engines don't cool off. Accordingly, the engines stay at operating temperatures for much of their lives (I would wager that more NYC taxis are retired from suspension and body fatigue or transmission damage than engine wear), a condition that 's the BEST operating climate for the engine and its oil. This situation reminds me of a stupid TV add Honda ran several years ago where they had a car running on a treadmill and several serious-looking men in lab coats with clip-boards were watching. The sell line was something like "This Honda has been running continuously for over 100,000 miles and it's still running strong." Well, duh, that's heaven for an engine; it's likely to run forever under those conditions.

Contrast that to how most of us run our cars--we start in the morning from cold, run a few miles to work or to the store, stop and let the engine cool off. Repeat endlessly. That running schedule is a killer for an engine. As I said in my first submission to this thread, cold starts are the worst for engine wear. Since synthetics remain more fluid at low temps, they are best at minimizing wear (do this experiment yourself: place some regular oil and synthetic oil in the freezer and see which one pours easier the next morning). At operating temps, I agree that any good natural mineral oil is up for the job of lubrication and heat transfer, but that's not where the critical difference lies.