Posted this in someone elses thread but didn't get much of a responce.
What does everyone think about this claim? Looks like a lot of high horespower cars break in with synthetic oil now.
http://www.mobiloil.com/USA-En....aspx

Myth: You should break in your engine with conventional oil, then switch to a synthetic oil like Mobil 1.

Reality: You can start using Mobil 1 with SuperSyn Technology in new vehicles at any time, even in brand new vehicles. In fact, Mobil 1 with SuperSyn Technology is original equipment (it is installed at the factory) in:
Aston Martin
Bentley Amage and Bentley GT
Cadillac CTS, XLR, SRX and STS
Chevrolet Corvette
Dodge Viper
Mercedes-Benz AMG vehicles
Mercedes SLR
Mitsubishi EVO
Pontiac GTO
All Porsche vehicles
One of the myths that surrounds synthetic oils is that new engines require a break-in period with conventional oil. The fact is, current engine manufacturing technology does not require this break-in period. As indicated by the decisions of the engineers who design the high-performance cars listed above, Mobil 1 can be used starting the day you drive the car off the showroom floor.


Modified by sp00led at 6:06 PM 3/3/2006


Modified by sp00led at 6:06 PM 3/3/2006

 

hey man, that link is broken

 

sae 30 weight works great for me.

 

fixed link

 

nice find.

 

in fact it may be possible to run in engines with this especially made Supersyn 100% synt oil.
But you have to think what really is wearing when u break in a engine from the end of the eightys till now... All the parts are cast or forged with really small tolerances... so theres almost nothing to wear except the -->piston rings!<--

BTW (talking about myths...):
Engine bearings are not made to wear at ALL... many ppl think they should be carefull with them cause they will wear. THEY have (100% sure) no need to run in.

THE ONLY STEP TO PROTECT them (and everything else) is to turn the engine a few times before turning it on to ensure the oil pump gets oil in every single part of the engine.

As a fact they most of the engines parts dont rub against eachother. An oil film stays at all times between them (oil as any liquid is non compressible). If they did (or do) rub against eachother they wont last too long (minutes maybe) without scarring and/or breaking.

Back to choice of run in oil...
From what i know about the auto industry, engineers are making engines a bit different nowadays... especially in regard to piston rings. The materials used to make the rings, its hardness, width etc has continuosly gotten away from our traditional ring... the reasons are many as being able to run much LEANER mixs and pushing the top ring closest to the top of the piston (this things actually help to not polute and increase mileage)... well you can investigate this all with SAE and other institutions. im dont want to get too much into it or be scientific about it.

Thing is: Its very Important that you actually get the rings to seal properly in the first few miles the engine runs. After that, they wont get much run in at all... So if you use 100% synth oil with rings that need a semi synth u'll for sure get not that good of a ring seal... yeah the engine will run good, but it could be running better and accelerate crisper...
And yes these new thinner, high temp resistant rings manufacturers are puting into engines can break in with 100% synth... cause they seal much faster than conventional rings!

For what this board should discuss, HONDAS, rings are traditional. so better give those rings some semi synth in the first 40 miles, flush it, put semi again and after a couple thousand miles change to 100%synth

There are many theorys out there, specially in BBoards. You must should choose what you believe best. Anyone can just write after my post: Im a mechanic for XX years and i wouldnt do that because Y and Z...
I dont care, i know what i said and maybe i'm also an auto engineer with experience


Sorry for my english

 

they only run that straight from the factory because its designed that way for the engine and is spec. by the man. other than that your myth is not a myth and is true. synthetic just helps proportion heat better and provide a little better viscosity

 

Don't take this personally...but if an oil company told me the sun comes up in the east, I would look for it in the west. Anyway, I think they are referring more toward factory new cars/engines and not rebuilds. A slicker oil will not allow the rings to seat as fast as a non-synthetic, in my opinion.

 

Earl most of the manufacturers have test equipment for the engines and this is where the actual break in occurs while being tested. I seriously doubt the oil used in this procedure is synthetic oil. I think they put the synthetic in after the test period. As the oil used in the test and initial break in would probably have some residue in it.

 

As long as we're debating via manfacturer websites, how about this

http://www.royalpurple.com/techa/faqsa.html#ro6

 

vtecmissile is right. manufacturers assemble the engine and start it. then get them warm and do many passes up till the red ALL this with regular oil.

But as i said, many new engines already run in with 100% synth oil just because they dont have that much ring material to run in. these rings are completely different from what 80s-90s cars have

 

Or maybe this is because by the time the car gets to the dealer, the manufacturer considers the engine broken in.

 

Thats why you redline it when you test drive them! hah

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by sp00led &raquo;</TD></TR><TR><TD CLASS="quote">
Myth: You should break in your engine with conventional oil, then switch to a synthetic oil like Mobil 1. </TD></TR></TABLE>

This is not a myth. For example, my 2002 Civic Si came with break-in oil with specific instructions not to run synthetic until the engine was broken in.

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by sp00led &raquo;</TD></TR><TR><TD CLASS="quote">
Reality: You can start using Mobil 1 with SuperSyn Technology in new vehicles at any time, even in brand new vehicles. In fact, Mobil 1 with SuperSyn Technology is original equipment (it is installed at the factory) in:
Aston Martin
Bentley Amage and Bentley GT
Cadillac CTS, XLR, SRX and STS
Chevrolet Corvette
Dodge Viper
Mercedes-Benz AMG vehicles
Mercedes SLR
Mitsubishi EVO
Pontiac GTO
All Porsche vehicles
One of the myths that surrounds synthetic oils is that new engines require a break-in period with conventional oil. The fact is, current engine manufacturing technology does not require this break-in period. As indicated by the decisions of the engineers who design the high-performance cars listed above, Mobil 1 can be used starting the day you drive the car off the showroom floor.
</TD></TR></TABLE>

Take a look at these manufacturers. Most of them are high-end vehicles that probably had their engines broken in on run-in stands.

It depends on the type of rings you are using and the method you are using for breaking in the engine. Honda's use low-tension rings in order to reduce friction and increase fuel mileage (and power). They are sensitive to break-in and if they don't conform to the cylinder walls properly they will not seal well. When in doubt, consult the owners manual (if it is a new car). If it is a rebuilt engine, consult the ring manufacturers recommendations. Do not listen to the oil companies marketing department (I think somebody mention something about the sun rising in the east . . .).

Opinions on break-in procedures seem to be all over the place on this board and most of them are hear-say and a lot of them are just plain paranoid. You don't need to change your oil and filter every 100 miles for the first 1000 like some people say or even after the first 40 miles (if you are worried about debris in the oil, change the filter and top off the oil. If your engine has that much crap in it that you need to drain the oil there was a problem in the first place). Although I will admit if you change it once after 40 miles like one poster said - it can not hurt. You do need some slight abrasion to get the rings to conform to the shape of the cylinder they are going to be riding in and synthetic's lubricity is just too high too allow this to happen in most cases. I also see people babying their engines thinking it will somehow be good for the engine. You need to get on it every once in a while during break-in to help seat the rings. Usually the procedure is to bring it on the highway and hold it in, say, 4th gear and run it at about 3/4 throttle to WOT from roughly 3000 - 6000 rpm and then decellerate still in gear back down to 3000 and repeat this about five times in a row. Do this several times throughout the breakin period. The acceleration during WOT caused gas pressure behind the rings to force them outward toward the cylinder walls, thus 'wearing' in the rings and the decelleration causes oil to get sucked by the rings and flush out debris that might have been created during this procedure.

But that's just my $.02

 

My friends has a STI, blew up the first motor, went back to stock a new shortblock, ran full synthetic oil in 3,000 miles the car was chewing up oil like it was going out of style. Tore it down, cyclinders were glazed, once again got a new shortblock, ran the same oil again, royal purple, i told him not too, after another 3,000 miles was going through oil. I'm a firm believer not to run synthetic on a new motor until it has some miles on it. Take this for what it's worth, i know that i'll never do it in my own car and thats all i care about.