Are Oil Catch Cans better for GDI Systems or are they also recommended for all types of cars? Is every car designed to fit an Oil Catch Can or do certain adaptations have to be made with hard labor?
You are asking the same questions in different ways in multiple posts. Please don't do that. (Topics merged.)
No. Blowby is when piston rings do not seal completely allowing gases to enter the crankcase. There are usually two connections on your valve cover. One goes directly to the air cleaner, and the other, with the PCV valve, goes to the intake manifold. The hose to the air cleaner recycles some of the blowby back to be reburned in the engine. The PCV valve is a vacuum assisted (intake manifold vacuum) method or reburning this blowby. The amount of blowby is a function of the piston rings, which all engines have to some extent, whether they have a PCV valve or not.
You should use a new PCV valve with each 5000 mile oil/filter change as cheap insurance against pressure build up in the crankcase. Oil catch cans are no better than the people who remember to empty them on a regular basis. A new PCV valve is cheaper than a catch can.
On 99% of non-GDI N/A cars the PCV is good enough at removing oil vapors without the help of aftermarket add-ons. A lot of those engines feature oil separators that do the job excellently.
As far the the second question - most cars are not designed to have a catch can if it’s non-oem aftermarket.
This doesn’t mean you can’t install one, its just that engineers don’t put in effort to design a convenient way / place to install an aftermarket system
What are the many ways to prevent and/or reduce/treat blowby? Would and Oil Catch can be the best method or changing the PCV Valve at 50,000 miles? Or maybe just doing the Italian Tune Up more often?
If it's a car/vehicle you just purchased second hand and has lots of blowby, the best thing will be to change the oil more frequently. Keep the oil clean so it won't cause any more damage.
If it's a brand new car, do a break in for the engine, and change the oil and filter every like 5000 miles.
If you have an older car, like pre variable valve timing, then you can probably put in a thicker heavier oil to help reduce blowby. However, if its a modern VVT engine, just use the oil it was made for, or other bad things may happen >.>
I've heard from a carburator guy on youtube that he cleans his pcv valve every oil change and changes the pcv valve every couple oil changes. It might be different on modern cars, but do look at it once in a while and clean it with some brake cleaner.
The italian tune up is for cleaning carbon out of the intake valves, so that wouldn't really help with the blowby.
Ok, no problem. Thank You.
Does a push-rod naturally aspirated engine become less prone to carbon deposits and/or blowby?
Not necessarily. Although any non-GDI engine will be less likely to build up carbon on the intake valves, problems like a badly-tuned carb can make the engine run overly rich and cause carbon buildup. Any worn engine will have lots of blowby. (Decades ago I had a Rambler American with a flathead six - even cruder than a pushrod engine - that had blowby like crazy due to worn piston rings.)
Do cars before the 1960's without a PCV Valve have more Blowby than cars with one?
Not if they were in good condition. Prior to PCV a road draft tube was employed to draw crankcase vapors into the atmosphere while the car was using. That's what caused the dark streak down the center of roads in old TV shows and movies. (The old Rambler American I mentioned was a 1961 model that had a road draft tube. At that time only California required a PCV system.)