Looking at Honda engines. Are all the Honda engines GDI only ? I see the V6 in the Honda Pilot, are there any Honda engines that are GDI but also port injected, I'm concerned about the oil build up on the valves with a GDI engine.
You should be as I wouldn't buy a GDI only because of reasons you mentioned. And no they are not all gdi.
It depends on the engine you get with the car. GDI is actually better than port injection (precise injection > perfect mixture > maximizes power and efficiency), but with all things in life nothing can be perfect lol. As you stated, carbon build-up will occur on the valves because gasoline is not washing over them that a typical port injection would do. It's not a terrible thing that will ruin the engine...just extra maintenance to get the valves walnut blasted every 70k miles.
But can't you have the best of both worlds? Yes, and I believe Toyota is combining port and direct injection in some of their modern engines. But again, it comes at the cost of being a super complex setup! Basically the fuel system is doubled on the engine side of things (not really at the tank, unless there are two fuel pumps).
Todays 2019 Corolla Scotty reviewed had both port fuel injection and direct injection and was very complicated.
@kerem
Yeah, it's honestly a great idea! It's a great solution to the carbon build-up we all don't like. But when it comes time to fix it...you're gonna need to empty your wallet lol.
In theory gdi is better, but port injection with todays control is good enough and better imo. Measuring a cup of fluid doesn't require an microliter calibrated container as it's overkill and too many other variables and their greater tolerances/variances have far greater impact, like the metered air (maf) in determining a stochastic mixture... so no use making a cake with microliter calibrated cup when you use other containers for measuring the additional ingredients required for the cake.
And on the carbon build up, there's other ways to provide PCV (cause of carbon buildup on valves) than feeding atomized oil to the intake air mixture... but that's another story for another day...