3116Bullitt08, While what you say is generally, especially for n/a engines you are overlooking how adding Boost paying in the role. When you add Boost to an engine, you increase the pressure being "forced" into the combustion chamber. This extra pressure can force a little more "blow-by". Not enough to indicate internal problem but enough to cause additional pressure through the PCV system. If you add Boost, you must have something to catch this additional vapor. This is just one of the by-products of adding boost to a engine.
Ford did not account for this with their ecoboost so the additional vapors are going into the intake causing carbon build-up on the valves.
Even with the 4.6 3v engines, there are a lot of people who found carbon/sludge on the "Motion Plates" in the intake. This is also caused by the oil vapors from the PCV system.
I didn't overlook it because I felt it goes without saying what happens when you add a huffer or a turbo. Plus oil is a lubricant to both IIRC and when it's introduced upstream of the intake it doesn't have anywhere to go but into the intake.
Apparently Ford didn't/doesn't feel it's an issue or they would have increased the ring tension to compensate for blow by or they don't because the added tension would increase wear to the point of shortening the life of the rings.
In case you weren't aware Ford built an F150 eco and drove the **** out of it in a variety of ways and tore it down rebuilt it and drove it some more. IIRC after one tear down with over 100k miles the engine didn't show oil deposits, the front side of the valves were extremely clean. The rebuilds involved gasket replacement so as to monitor wear over a long period of time.
What people do and how they maintain there's including the type of fuel and oil can make a big difference. Back in the '70's 351c's began having excessive oil deposits/sludge build up, turns out that Quaker State changed there oil and because IIRC how clevelands water was routed the paraffin turned into a solid in the top part of the engine creating sludge.
I did address oil on the valves in my reference to road draft tubes. ALL ENGINES will suck, in the case of PCV systems, oil into the intake because some amount of oil mist from the whipping of oil by the crankshaft in the pan. The dripping oil, crankcase gasses and eventual smoke and excessive oil dripping from poorly maintained or from engines ran hard led to the invention of the PCV system. That didn't or hasn't changed what goes on inside the engine.
3V don't operate any differently than any other engine and 1 extra valve doesn't change anything. I'm not aware of any engines failing prematurely because of oil deposits. I wonder if the issue isn't the 3V but more about how hard some of those engines are run because of the cars they're in? Run a 302 hard and you'll start blowing oil out of the pan gaskets. Run a 3V hard at higher RPM's and it goes without saying that the oil is going to get pulled up by the crank far more than a grocery getter therefore more oil gets sucked into the PCV system. High RPM is why Boss 302's came with windage trays to help keep oil from being whipped around by the crank robbing HP and kept from getting sucked into the PCV system excessively.
These engines, 3V, just like the ones from days long past will and have run 100k miles many times over without any issues if maintained regularly without adding any catch cans.
I put one on my car for 1, because I don't drive it much and 2, I got it for less than a c note at a show.
Excessive carbon on the front side of the valve and intake runner comes from reversion during overlap which can be exacerbated by changing cams with more overlap. Not Ford's problem.
Ford isn't going to and shouldn't do anything because run of the mill engines don't have issues. Put a huffer on a car not designed for one and your on your own, even if Ford warranties it, it's not for excess oil in the intake.
Do 500's have an oil consumption problem, at least ones that aren't run hard?
Again people will sell you anything.
Are catch cans a need? Never have been, probably not now either.
If anything there was a "need" before todays oils and cleaner burning fuel and computers. If anything it makes more sense to put it on an old piece of iron even with todays oils and fuel.
Will it give some people peace of mind? Probably.
If your getting much more than a tiny bit between OCI you probably have other issues so in that case it could be an early warning system.