I8ABMR

I am addressing a real problem that ALL DI engines have with carbon deposits from burning PVC oil vapor. If you have worked on planes then you know how DI works and you know what I am saying about the auto DI engines and deposits is 100% true . What I'm suggesting is essentially the same as reducing serum cholesterol levels to decrease chance of heart disease. You can reduce chance of heart attack and stroke but not eliminate it 100% . Just better overall health with less deposits / atherosclerosis ( we will discuss lipid deposits and inflammation that causes artery build up and plaque development as equal to the sticky mess that lines and covers valves ) . Makes total sense if you think of lipid deposits in the same way carbon builds up ( but the carbon generally never clogs it totally like a blocked vessel / infarct). Your example of tonsils doesn't not apply because some people , including myself , still have mine after decades on earth, BUT ALL DI ENGINES WILL BURN PVC VAPOR and deposit carbon on the valves (and even with Toyotas better injector design relative to Ford, Audi, Mazda, etc ). Its a downside to ALL DI engines. IMHO it would make no sense not to try to avoid or at least reduce the amount of vapor that the engine will inevitably burn.


In both cases there is a clear benefit in the long term. Managing a catch can that is extremely unlikely to fail and or eating a better diet is the same . Both a little pain but better in the long run and for performance the engine will getting the cleanest possible intake air that will not cause detonation under extreme loads and high engine temps. Both are undeniable. You have oil going into your intake manifold through the PVC system and since DI engines are more prone to deposits ( all DI engines do to some degree ) why not manage and reduce ? I am thinking the AO separator will keep my engine happier when its at 100k. Its only got 38k miles.

To each his own and I respect what you are saying because I too DO NOT have any visible smoke , but because I know direct injection engines are more prone to burning that PVC vapor and my cars mileage is still relatively low for its age I'm going to give it a whirl. I am too curious as to what is going to be collected. If its nothing Ill just yank it.




This is a great technical video as to why DI engines have issues with deposits and why a catch can ( AO separator ) will benefit the engine performance and fuel mileage as the car ages : ( FWD to 4:30 for a fast look)



Another Brief Video :

Compthis

iTrader: (1)

When the stig drove the car for top gear he experienced Smoke as well. I want to assume that the car was new or almost new when he tested it. I push my car hard and I'm sure he pushes cars much harder. For him to experience this smoke is just not a coincidence but rather a common problem with the car. I see absolutely no point to replace a failing part with another part that will fail. I also refuse to be the test mule for trying to resolve the problem at its core. I don't have the liberty to access a garage with tools nor possess the mechanical knowledge the try and figure this thing out. I also refuse to pay a mechanic 1000's of dollars to diagnose and come up with a solution when a $160 part will do the job for the time being. I have no fears, it's an engine, not my life.

lobuxracer

iTrader: (2)

And of course the guy in the video is not selling anything, and he fully understands we have a combination of direct and port injection, so we don't have plaques building up on the intake valves. Also, he fails to address EGR which is done now with cam timing and also causes deposits in DI engines.

Mine doesn't do it. It won't get "fixed" and I won't add another device which could also fail and cause complete destruction of the engine from running lean with a cracked tube or broken connector.

I8ABMR

You are absolutely correct in that Toyota has the better design because of the multiple injectors and improved crankcase oil separation, and they also use EGR / valve timing overlap (using VVT) to keep things clean . On top of this , relative to the VW / Audi ,GM , and BMW direct injection designs with the insane build up issues and even TSBs because the issues are so common , Toyota's (and Mazda's sky active DI ) engines suffer from the least carbon issues , and Toyota's engines prove to be reliable even with the added design complexity . BUT all DI engines will still suffer from carbon build up . Adding an oil catch can to the PCV system should be effective at significantly reducing, although not eliminating, valve deposits from what the system can not or will not effectively remove before heading back into the intake manifold, while maintaining the cleanest intake air and burn possible . I'm going to give it a try and if I don't see much collected I will simply have it removed. If not I will use it to keep things cleaner inside the engine with the inevitable track days that are coming ( 7 in 13 months ....she needs all the help she can get LOL ).

Not sure what the failure rate on a catch can is but the design is so simple and the openings on the lines are so big I can't see it failing. At $160 bucks I'd rather just remove it every 100k miles and install and all new AO separator rather than cleaning it.

Defratos

Thanks for the tip, I tried uncliping the clamp today and haven't had any success, I'm close to breaking the thing trying to get it open.

I used a flathead screw driver on the tabs but it won't budge, I'll try again in a few days.

...and yes I know my engine bay is dirty , as it says profile, I'm located on a sand dune so every day its sandy everywhere

RRRacing

iTrader: (1)

You could just as easily have a cracked OEM PCV tube just as easily as a failed AOS piping. If the PCV pipe has a major leak, it will be more than obvious because your car will idle extremely high and immediately set off a CEL. A minor leakage CANNOT damage your engine, but will almost immediately get a CEL for "system too lean." So with all due respect, billing this as a risky mod that could cause "complete destruction" of your engine is really pushing it to put it mildly.

If you want a 100% full proof fail safe setup, you can simply add another PCV valve placed at the intake manifold, but this is not necessary and will reduce somewhat the effectiveness of the AOS.

I have tuned hundreds of Subaru's which also have oil ingestion issues. With the STi/WRX it is a bit different because due to the boxer engine, most of the vapors are coming from the valve cover breathers rather than the PCV, whereas with the ISF its the other way around -- but the problem is essentially the same. Highly tuned STi engines are running much closer to their mechanical limits, all STi tuners that I know of are religious about running AOS's, its simply good practice, especially on track driven vehicles. In the case of highly stressed turbo 4 cylinder engines, the added margin of safety actually makes the difference between saving an engine and "complete destruction."

The effects of oil ingestion on ignition timing are obvious and any reputable tuner will vouch for what I am saying.

I have documented how much oil this car ingests via the PCV system. I am 100% confident that anyone who takes their F to the track will confirm it. And I will put my money where my mouth is by saying that if you take your F to the track with our AOS, and do not see significant oil accumulation, I'll give you your money back.



-Rafi

sraban

Air Oil Separator is not a concept RR Racing invented -- we simply designed one for Lexus. If you Google AOS, you will find many such products designed for other car models and most race cars. If you drive your car to work and back or to the grocery store, you do not need to modify anything on a Lexus. However, Lexus designed their cars for an average driver, and they have many other design considerations such as commonality of parts, the ability of an owner to do maintenance, etc. When IS-F came out, several test drivers concluded that its steering feel was not quite as good as of BMW M3 -- why didn't Lexus design the IS-F to be better than M3 in all aspects? Our USRS (lower control arm bushing and housing) makes an IS-F as responsive or better than an M3.


Rafi and I were on the first track session when we noticed a lot of smoke coming out of our IS-F and where we took the first photos of oil coming out of PCV. After a very careful consideration Rafi concluded that IS-F requires an AOS, and even then we only introduced this product after many hours of testing on the track and on the street.


We are constantly evaluating and improving our products. I am certain that over time, we will introduce new improved versions of the AOS for Lexus IS-F, RC-F and other models.


-- Simon, RR Racing Operations

Defratos

I'm not as technically knowledgeable as you guys but I've had this can installed for around 4 days (I get to hammer my car daily going to work and back) and the oil is slowly collecting, I live in an extremely high temp country and consider that I take good care of my car. So far I haven't seen a disadvantage and I guess this also explains why my engine oil keeps burning up. As one of my friends noticed my car does puff smoke when driven aggressively, let's see if this unit helps improve things.

MileHIFcar

Had another CL member help me install mine on Friday (10th) before we went for a 360 mile jaunt/spirited drive to bishops castle in the mountains. I thought this was perfect timing as to installing the AOS as I knew I would be driving the car well into triple digits and when we were hitting the canyons pretty hard I was hitting 5 bars on the oil temp gauge. I was pacing and trying to hang with a supercharged NSX (I did pretty well considering how big the F is and the weight disparity)

I let the car cool down when I go back overnight and just checked the container/tube to see what it caught and the pics are attached. As you can see the amount of oil in the separator is not what Rafi got in his track session, but, nonetheless it's still oil! And it would've went into the combustion chamber and lowered octane/caused deposits, fill in the blanks______ etc........

I for one will not be asking for a money back refund from Rafi as it's a well designed and engineered product for the F and encourage anybody with a F and are concerned about the long term health of your engine this certainly won't hurt and will probably extend the life of the motor or reduce some maintenance down the road. It's about the cost of 4 tanks of gas

lobuxracer

iTrader: (2)

OK guys, I'm not here to bash the concept, I understand it quite well and I know the octane rating of engine oil can cause issues if it is ingested. I've only been building engines for about 43 years, so bear with my questions.

What do you warrant with your product? If your tubing, connectors, or trap crack, causing detonation, and crack a ring land (which has never happened to the OEM configuration) what will you cover? The tube, the catch can, the engine or all three?

Here's my problem - what you call extensive testing is a trip around the block for an OEM. Engine configurations have MILLIONS of test miles under a very wide range of atmospheric conditions before they are certified. What testing protocol did you use, and how did it fare? All I heard was we've tested this thing at the track for an unspecified number of sessions and about 10,000 miles on the road, ostensibly all in New Jersey. Because the OEMs test in hot, cold, low altitude, high altitude, low humidity, high humidity, across a fleet of cars, the likelihood of an OEM part failing, especially a rubber tube is tiny because of the exhaustive testing protocol the OEMs use, even on turbo engines where all the hoses turn to glass over time. I worked on a bone stock turbo Supra once where every single hose broke in my hands, but the engine didn't have a single leak when it arrived. Ask anyone who owns a turbo Supra. Even then, when the 2UR was released, Aisin's waterpumps failed early. Radiator fan bolts failed early. Both in large enough numbers to require redesigned parts. Why should I believe your product will not have issues and will not present a problem at 10k, 20k, 30k, 50k (the minimum Lexus warranty) down the road, and how will you address the issue if I (or another customer) have an issue?

dcguy

I as well had just installed the aos and ran with the nsx crew ripping through the twisty mountains. Definitely wasn't easy on the car and pushed the limits keeping up with the light versatile nsx. Pulled my catch can off soon as it was cool enough for the bare hands. Sure enough around 4 drops of oil and a thin coating all over the catch can, not much, but never the less, 4+ drops of oil saved from self ingestion. This was only for a one day drive as well curious to see what it catches in a month.

RRRacing

iTrader: (1)

Lobuxracer-- I understand and respect your skepticism regarding many aftermarket parts, but using your logic, we should always keep our cars stock, because if an extensively tested OEM part fails (as they often do), then surely any aftermarket part will fail as well? If every aftermarket part had to be tested over millions of miles and warrantied for 60,000 miles, we would have ZERO aftermarket parts for any car, and the Supra guys would all be driving around in a 300hp overweight 2 door "sports" car. That would be a real shame, because as we all know, the Supra transforms into something amazing when well modified.

When you design a part such as the AOS, you have to consider the failure mode. As I mentioned before, there are two possible failure modes:

(1) Worst case: AOS hose completely cracks in half and falls off -- In this case, it will be OBVIOUS because your car will surge and idle like mad, indicating something is terribly wrong. You will also get a CEL very quickly with this scenario, as the O2 feedback will result in much larger than expected compensations to keep the target AFR.

(2) Slight leak in the AOS system -- no way will this lead to a failed engine or detonation. At high load, a minor air leak represents an extremely small proportion of the total metered air, it will not affect A/F ratios at all. Also, at higher loads, the ISF has a wideband sensor to compensate for closed loop off-target ratios, so even lean AFRs due to a moderate leak will self correct.
At idle, where an air leak will result in excessive AFR correction, you will get a CEL very quickly. But there is no way lean ratios at idle will endanger the engine.

-Rafi

PS, if I or one of our customers ever experiences a leak, we will issue a bulletin and remedy the situation.

redspencer

iTrader: (1)

I was just reading the latest comparison review which pits the RC-F against the ATS-V and the M4:

https://www.cars.com/articles/which-...1420680695167/

Besides the RC-F getting destroyed in this head-to-head comparison, I noticed a particular comment in the article about the RC-F which reminded me of the Top Gear video of the IS-F and this AOS thread.

PDP180180

iTrader: (3)

Nice find.

Good to see this is still a potential issue with the newer RC-F as well as our F's.

Whilst I understand it won't be for everyone, I personally think it's a bit of a no-brainer for the price.

Can't wait to get mine and install it.

MileHIFcar

Quote:

Originally Posted by Cars.com
As the judges finished their testing runs; The RC F we tested bowed out midday track workers noted it was belching blue and black smoke, so we parked it. In later driving on regular roads, we noticed no further issues.


Hmmm... seems just like what Rafi said when he noticed on that top gear video when the Stig was doing some hot laps in it before the camera caught the smoke coming out of the F. Sounds like it's the same issue with the RC F when driven hard, or on the track. I'm surprised the engineers didn't add some sort of preventative measure(s) to the 2UR GSE going into the RC F platform considering they had time to improve on the performance aspect of the motor?