Direct injection (GDi) went main stream in the late 1990s and early 2000s. The same technology engineered to squeeze more power from less fuel quietly created one of the most common maintenance headaches in the modern automotive repair game- carbon build-up. The parts most at risk are the intake valves, cylinder head ports, intake manifold/throttle body, piston tops, and fuel injectors. In traditional port-injected engines, fuel washes over the intake valves on every cycle, keeping deposits from forming. Direct injection engines remove that cleaning mechanism entirely, and that means the valves aren't cleaned in the same way they are with port-injected engines. Carbonization can directly cause ignition problems, rough operation, fouled spark plugs, and misfire codes. Switching to Top Tier can cut existing intake valve deposits by 45%-72% over 5,000 miles. Meanwhile, conventional motor oils are more likely to suffer from oxidation and thermal breakdown than synthetics, which can increase deposit formation over time. Also, oil catch cans can help to intercept oil vapor and contaminants from crankcase gases before they re-enter the intake. For more information, read: What Engine Parts Are Most Susceptible To Carbon Buildup?
Not sure what to make of that offering above mine but carbon build up is certainly a relevant issue Tom. I've read it accumulates on valves even sooner on turbo charged applications. Addressed it twice prior to major mods on my 335's (many walnut blast, I chose a method similar to the one in the video). How to Clean your N54 Intake Valves AT HOME (+ Oil Filter Stand DIY)
I have a Billet Technology oil catch can on my 6.1. For only about $100, it is a cheap investment. Also, it looks good. Better safe than sorry. Oil Catch Cans | Dodge Challenger Forum