My 2021 v6 atlas manual says to use regular octane fuel. Is there any real benefit to using high octabe? Is it still better to use high octane vs regular or is it just a waste? Thanks
Top Tier while certainly the best standard in gas to use, has zero to do with carbon build-up on the backs of the intake valves b/c the fuel never touches them in a DI engine.87 but use Top Tier fuel. This will help slow carbon build up on the valves due to it being a GDI engine. Shell, Exxon, BP, Valero and some others use Top Tier Fuel.
How exactly if it doesn't touch them? It's not doing a thing to the valves - only the injectors themselves (a positive!). Folks have debated this issue in online forums and social media for a long time including fuel type, oil quality, "Italian tune ups" and catch cans. None of it will prevent some build-up from happening on the back of the intake valves in a DI engine with no port injection to get some fuel/cleaners on the back of the intake valves. Most modern DI engines are not having issues like the earlier engines had and at worst, if you keep it long enough and have misfires/issues related, you get a walnut blast. I realize some bits online will reference Top Tier as helping but it doesn't....it physically can't.I am aware the gasoline doesn't pass over them. The Top Tier Gas helps keep the carbon build up down nonetheless. That's from my reading on it.
I have and my comments are based on it. For general combustion chamber cleanliness including carbon build-up...yes. Back of intake valves in a DI engine that the fuel never touches...no. Just not much you can do fuel-wise/additive-wise on a DI engine to prevent it from getting some carbon on the backs of the intake values unfortunately but for sure, use Top Tier-branded fuels.There is plenty of literature on the subject available on the internet. I encourage you to read it for yourself and formulate your own opinion based on it.