mikeyr

synthetic is so slippery that the motor will never fully break in

90crvtec

You're all forgetting that the bulletin from Honda warning about switching to synthetic only mentions early model AP1s. I think it's foolish to continue posting this to new users as the engine designs have clearly changed between AP1 and AP2 models. It's common knowledge that AP2s don't burn nearly as much oil as an AP1, many AP2 owners report zero oil consumption. To me, this indicates that the motor is mostly broken in from the factory. An AP2 that has nearly zero oil consumption when new sounds like a pretty tight motor to me. I say run synthetic after the first oil change, you won't hurt a thing.

Finally, synthetic isn't "too slippery" for a new motor. That's complete, unsubstantiated BS. How do you explain synthetic factory fills (Audi, BMW, VW, Mercedes Benz, Corvette, etc. etc.)?

90crvtec

Just to specifically answer your question, the common school of thought is that waiting until 10k to switch to synthetic allows the rings to fully seat with the bore. When an engine is new the rings and the bore surface aren't worn in yet. Instead the surface of the bore is rough and contains small gaps that can allow oil to get by the rings and into the combustion chamber.

The common thought here is that synthetic oil has better lubricating properties and a higher flash point (read: synthetic is hard to burn), this makes it harder to burn in the combustion chamber and it could end up interfering with the piston rings properly seating against the piston bore. If this happens you run the risk of having an engine that continually consumes oil because the rings never had a chance to fully seat or wear in from the factory. Ideally, the rings and bore should wear against each other and produce a smooth mating surface that allows the rings to effectively seal the piston from blow by out of and in to the combustion chamber.

However, there's another common school of thought that the AP2 has a different ring design than the AP1. Also, the stroke of the AP2 is longer, some have speculated that this too can aid in reducing oil consumption (I'm sure the lower redline helps to some extent as well). The bottom line here is that by the time your car is delivered to you it already has some miles on it. Any critical break in concerning the ring to bore mating surface has already started, by the first 100 miles your rings will have "broken in" about as far as they'll go for the life of the motor. I think people over hype the whole 'don't switch too early' story.

Chazmo

^ I don't know if the F22 has a different ring design, 90crvtec. What we do know is that Honda started honing the cylinder bores differently in 2004, and my understanding was that applied to the F20s and F22s that were sold after that point world-wide. This new honing process seems to have demonstrably lowered blow-by presumably by tightening up tolerances.

Also, I'm not at all sure that longer stroke equals less wear... Bottom line is that piston speed at reduced redline for the F22 is roughly the same as the F20.

I see no reason *not* to follow Honda's recommendation not to use synth until 10K or so. I would recommend to the OP not to put in synth until then, but to change oil right after track day.

JackS

Everyone has made some good points concerning the best time to begin using synthetic oil. I think we can all choose a time based on our best understanding and all of us will be in good shape in the end.
Some people may choose not to use synthetic at all. I would suspect that this is also a completely reasoned choice.
Honda neither promotes or discourages the use of synthetic motor oil.
Personally I'm going to start using it at 10k. This makes me comfortable but i realise any other time schedule may make someone else feel the same.
Choose your time and choose your oil.
Relax, drive, be happy.

90crvtec

[quote name='Chazmo' date='Mar 14 2007, 07:22 AM']Also, I'm not at all sure that longer stroke equals less wear...

Baby_Lexx

So you guys don't think that racing on the factory oil is going to be a problem, right?

Vitt

If you drive it enough (and rev it enough ), by mid-April you should be below 30% oil life, maybe even at the 15% interval. Personally, I would give it an oil change for a track day, especially if it's never been changed before. In fact, I did my first change at 5,200, and I used Mobil 1 since I had a track day coming up in a week or two after that change. I would use a synthetic, especially if the weather starts warming up in your neck of the woods. If the engine is gonna see some high temps from high revving all day, I think synthetic is the ONLY way to go to protect that baby from the extra stress it's gonna see in a track day. Just IMO.

I've had no oil burning issues whatsoever yet.

90crvtec

Once again, I think all this advice to wait until 10k miles before synthetic is unsubstantiated with the AP2.

Chazmo

You guys are entitled to your opinions, but Lexx, it's your car... the recommendation from Honda to wait for synthetic fill stands.

I strongly recommend a read through the oil journals thread in the under the hood forum so you can get acquainted with the fluids in your car. There are some terrific products out there for diff, tranny, and engine lubrication, as well as hydraulic fluids for your brakes and clutch.