oil has nothing to do w/ break in.
corvettes, and porsche's come straight out of the factory w/ mobil 1 synthetic, and still have a normal break in period, just like other cars.
its actually a GOOD idea to switch to synthetic oil early on in the engines life, b/c you will get a lot more mileage out of the motor, and it allows the synthetic oil to bond to the new metal, especially cams, and make a protective layer which causes less friction, and allows for a higher, free'er reving engine.

 

I have always thought it best to break in slowly, especially with newer, close tolerance engines. I changed my oil (02 WRX) 2-3 times in the first 5K miles, especially at 1K, 3K, 5K and then every 3K or so. I now have nearly 15K miles, and it is so smooth and quick! I play a bit a few days ago with an STI and she and I blew by several fnf others. Keep it clean, and if you want to use syth, that's ok, but my tuner (not a dealer) says use dino and change often. The temp here easily goes from -10 to +100 in the course of the year.

 

Wow, there is so much wrong information in the thread I wouldn't know where to start.

-st

 

Gents. All 2004 WRX STi's come from the factory with Mobil 1.

Switching to Royal Purple is a giant step backward as it is only a Group II lubricant while Mobil 1 is a Group IV lube. I read articles at length on this topic in a Mustang Cobra chat group last year. The author is a very schollarly Petroleum Engineer and is a definitive source of info on the topic.

The individual that feels the power loss may actually be experiencing a smoother running motor after the oil change.

The tuner recommending dino oil obviously doesn't understand thermal breakdown of oil in a hot turbo. He is way behind the times. I will post the abbreviated list I culled from ~50pages of reading on the topic someday if anyone cares to doubt the credibility of this info. Running a turbo without a syntetic lube in 2004 is insane!! esp these high boost motors!

 

My mistake. Its the Evolution that comes from the factory filled with Mobil1, good for them bad for us. Gonna get that easy to cook dino oil out ASAP now that car has 1400 miles on it.
As far as break in, I've always done a progressive ramp up on motors, and it was real easy with the Warning signal on the tach of the STi. Basically I bumped up 500 RPMs every couple hundred miles starting at 4000 rpms. By 750- 800 miles, I would let it find 6000rpms periodically but no multi gear runs yet. When I broke thru 1000 miles I celebrated by getting on it good and hard thru the gears till I found the fuel cutoff and got to experience the REAL downforce that wing creates!!!
I'd discuss oil issues with a Petroleum engineer before listening to all the bull flying around. Why do all the world's greatest cars come with Mobil1 stock if break in is such an issue??? Good luck answering that one without shooting yourself in the foot and no, its not paid marketing. Short of hammering them off the lot and not alowing appropriate cool down times, todays motors have to be abused pretty badly to have problems due to break in. The attachment in the follwing post is my brief summary of 50 pages of reading I did on the topic a few years ago when I got my 99 SVT Cobra.

 

See below for the realities of motor oil and what really is good. Notice change intervals I was guided towards. 3000 miles is BS unless you punish your ride routinely. This is from data expertly explained by a Petroleum Engineer in ~2000.

OIL

1. Group V - Only needed for racing
Redline
Motul

2. Group IV - Best for long drain intervals, towing,high temps, hard driving
Mobil 1: Tri-Synthetic formula
Amsoil
Mobil 1 Super syn is closer to a Group III but they have multiple new patents on a new molecule which should keep it as a top tier product. Still the best in its class as it has always been.

3. Group III - (cheap synoils) Only buy if the price is right as they are inferior to Group IV. Never buy if same price as Mobil1
Syntec
Valvoline Synpower
Pennzoil Synthetic
Havoline Synthetic/ Exxon Synthetic,etc

4. Group II Highly refined mineral oils
Valvoline All Climate
Pennzoil PZL turbo: Very good product except below 15 degrees
Royal Purple

SYNTHETIC CHANGE INTERVALS for my typical driving as I don't tow
1x/yr or 7500-10000 miles for Mobil 1 or better oils
5000 to 7500miles for Group III
3000 to 5000 miles for Group II

 

Just some food for thought, for those who believe in extended Break-in periods before switching to synthetic.

With Dino oil for break in: If you drive 1000miles at an avg speed of 40mph, at an average RPM of 3000rpm each piston will go through one stroke ONE MILLION ONE HUNDRED AND TWENTY FIVE THOUSAND times.

Now I am not a diagnostic expert for the wear properties metals or various engine components but that seems like an ample amount of strokes/cylinder on dino oil to "break in" various areas of the engine.

So those saying at or arround 8k switch to synthetic are saying that each cylinder needs 9MILLION strokes to be considered broken in??!?!?!

Sorry if it is off the current discussion topic, I just thought I would throw it out there

 

Luke, the world needs more logical types like you. Thank you!

 

lol ddski.

For some reason I was compelled to examine it mathematically.

But like I said, maybe for some odd reason 9million strokes is the magic number?!?! However I highly doubt it.

After reading the discussions back and forth on at least 4 subaru forums, The general consensus is that one should keep dino oil in for break in and then switch to synthetic. The time period is the contraversial variable.

So I say this, since wear does occur on metal parts early in the engines life, I changed out the factory oil at 1000miles with dino oil to get rid of any metal particles. Then since I like to change every 3k cause its easy to remember, I will put synthetic in at 3000miles.

To me this seems like a conservative way to go about it.