Royal Purple 5w30, 60,000 miles, Subaru 2.5L Turbo

[shakes]

Originally Posted By: JohnBrowning
hose silicone numbers are far too high for such a short run. Please tell me you do not have a cold air kit on this with a K&N or some other reusable air filter!!!!

I am suprised to see a 5W30 in a turbo Subie do this well!


It's got a K&N drop in filter.

 

[HighViscosity]

Oh snap!

 

[shakes]

whats wrong with a drop in filter? Do the cleaner and or oil add silicon to motor oil?

 

[pickled]

If you hold the K&N up to a bright light you might see what he is referring to. Some folks refer to them as rock catchers around here because abrasive dirt tends to trend up in UOA's with K&N usage. All and all they are less restrictive than a paper element, but there is concern over the adequacy of filtration offered. Also when they are not oiled properly post wash cycle they can do a number on hot wire MAF's. I've cleaned a lot of residue off from MAF's that is attributable to filter oil application throughout the years.

 

[bluesubie]

Originally Posted By: shakes
whats wrong with a drop in filter? Do the cleaner and or oil add silicon to motor oil?

Sometimes they allow more dirt to get into the engine. You generally, but not always, see cars with K&N's showing higher silicon.

-Dennis

 

[440Magnum]

Originally Posted By: ARCOgraphite
[
Ever consider street approved Valvoline racing 10w-30 synthetic? (not the NSL stuff) its got a beefy add pack with mondo ZDDP. I almost put it in my yaris, but reconsidered. Oh its dyed royal blue to boot! See the market? [/quote]

I have, actually, but I'm a little leary of oils that are overloaded on ZDDP and of racing oils in general for street use (hence my choice NOT to try RP XPR). Trying to strike a balance here, and maybe over-thinking it. But if I weren't prone to over-thinking, I wouldn't be posting on BITOG, would I?

 

[440Magnum]

Originally Posted By: shakes
whats wrong with a drop in filter? Do the cleaner and or oil add silicon to motor oil?


No- its all the sand that goes through the "filter" (and I use that term against my better judgement) that adds the silicon.

Seriously- K&Ns do have their place- on short-life race-only engines where long OCIs (and long engine life in general) aren't goals, and where running a larger paper air filter isn't practical. Weekend drag cars, autocross cars, etc. But for a daily driven car, the better filtration of a paper filter is worth the miniscule difference in flow (just what percentage of the time is a daily driver at WOT, anyway? That's the only time the flow of a K&N is even an advantage at all).

 

[Patman]

Originally Posted By: 440Magnum


Seriously- K&Ns do have their place- on short-life race-only engines where long OCIs (and long engine life in general) aren't goals, and where running a larger paper air filter isn't practical. Weekend drag cars, autocross cars, etc. But for a daily driven car, the better filtration of a paper filter is worth the miniscule difference in flow (just what percentage of the time is a daily driver at WOT, anyway? That's the only time the flow of a K&N is even an advantage at all).





K&Ns don't always show high silicon numbers. When I bought my 98 Corvette used I noticed it had a K&N air filter on it, but instead of immediately tossing it out (which was my first reaction) I decided to keep it in there and see what the UOAs looked like. In the end, it worked out pretty well, as I was seeing under 10ppm of silicon in my 6-7k OCIs. I now have a Vararam cold air intake on my car, and it came with it's own air filter made of the same stuff as the K&N (cotton gauze) and I'm seeing slightly higher silicon numbers now, but still not all that bad (especially considering I've got way more airflow into the engine now, as evidenced by the major performance increase I found on my quarter mile ET and trap speed)

 

[440Magnum]

Originally Posted By: Patman
[

K&Ns don't always show high silicon numbers. When I bought my 98 Corvette used I noticed it had a K&N air filter on it, but instead of immediately tossing it out (which was my first reaction) I decided to keep it in there and see what the UOAs looked like. In the end, it worked out pretty well, as I was seeing under 10ppm of silicon in my 6-7k OCIs. I now have a Vararam cold air intake on my car, and it came with it's own air filter made of the same stuff as the K&N (cotton gauze) and I'm seeing slightly higher silicon numbers now, but still not all that bad (especially considering I've got way more airflow into the engine now, as evidenced by the major performance increase I found on my quarter mile ET and trap speed)


At the other extreme- with the dusty conditions we're having this year *EVERY* one of my UOAs since March (3 different vehicles, all with paper filters) have shown elevated silicon. I'd hate to think what I'd be seeing if I still had a K&N in any of them.

Even with a little elevated Si, will a K&N trash an engine in no time? No. I ran one engine for over 100k miles with a K&N, and it was still running great when we sold the car with over 250k on it- no oil burning. I never did a UOA back then, but given what I'm seeing now I'm sure it also saw elevated silicon a lot of the time, especially the years it had the K&N. There was a slight performance increase in that car at WOT with the K&N (its airbox was a little undersized for the capabilities of the engine), but it just wasn't worth it for a daily driver.

 

[ARCOgraphite]

EVERONE seems to be complaining about high Si in the uoa, everywhere! Is the sample bottle blow molded HDPE or glass with a plastic cap? Most molding process use Si mold release compound. Also, how bout all that sand around the drain washer and nut - its a smalish sample - a tiny bit o'dirt could really overwhelm tha analysis. Q - Do you filter your sample through a mini funnel through filter paper??

 

[440Magnum]

Originally Posted By: ARCOgraphite
EVERONE seems to be complaining about high Si in the uoa, everywhere! Is the sample bottle blow molded HDPE or glass with a plastic cap? Most molding process use Si mold release compound. Also, how bout all that sand around the drain washer and nut - its a smalish sample - a tiny bit o'dirt could really overwhelm tha analysis. Q - Do you filter your sample through a mini funnel through filter paper??


I sample with a tube inserted down the dipstick precisely so I don't get contamination from dirt on the pan or plug.

But your point about silicone mold release compound possibly being used in the manufacture of the plastic sample bottles and the plastic "syringe" style plunger that I extract the sample with is a good one. However, I would expect that to wash away and the Si to trend down over time if the syringe is the source. Mold releases are usually hydrocarbon-soluble, so they should wash away after a few exposures to hot oil. If its the sample bottles, shame on the lab that supplies them for not ensuring that they're contaminant free!