What?Re: Thin 0W-whatever
According to the internet, "whatever" is much thinner than 0 under normal operating temperatures ... so we shouldn't blame the 0 unless there is more to the story than the viscosity
Obviously some whatevers are thinner than other whatevers
btw, as much as I don't care for DI engines, ours doesn't burn any oil after 124K miles.
What I don't understand is how can a DI gasoline engine get better fuel mileage when it runs so rich and makes the tail pipes covered in combustion soot? I'd think all the soot means it has to be running richer. My port fuel injected Coyote barely has any combustion soot on the inside of tail pipe, even after 5000 miles. It seems to burn much cleaner than any DI car I've ever seen.“The main reason OEs are going with direct injection is because of what I would consider to be unrealistic MPG requirements by the government,”
He’s seriously blaming the government for GDI issues. These things can't be made up.
“The main reason OEs are going with direct injection is because of what I would consider to be unrealistic MPG requirements by the government,”
He’s seriously blaming the government for GDI issues. These things can't be made up.
What I don't understand is how can a DI gasoline engine get better fuel mileage when it runs so rich and makes the tail pipes covered in combustion soot? I'd think all the soot means it has to be running richer. My port fuel injected Coyote barely has any combustion soot on the inside of tail pipe, even after 5000 miles. It seems to burn much cleaner than any DI car I've ever seen.
Mine doesn't either at almost 200k but I put super thick stuff in and dump it at 3k, I also regularly clean the intake valves.Re: Thin 0W-whatever
According to the internet, "whatever" is much thinner than 0 under normal operating temperatures ... so we shouldn't blame the 0 unless there is more to the story than the viscosity
Obviously some whatevers are thinner than other whatevers
btw, as much as I don't care for DI engines, ours doesn't burn any oil after 124K miles.
What I don't understand is how can a DI gasoline engine get better fuel mileage when it runs so rich and makes the tail pipes covered in combustion soot? I'd think all the soot means it has to be running richer. My port fuel injected Coyote barely has any combustion soot on the inside of tail pipe, even after 5000 miles. It seems to burn much cleaner than any DI car I've ever seen.
Diesels always run lean and they make lots of soot.I'd think all the soot means it has to be running richer.
My 1975 Civic and 1981 Accord had CVCC engines that applied a rich mixture around the spark plug.They can run rich around the sparkplug and lean everywhere else in the cylinder, whereas a PFI runs a homogenous mixture. The net result can be lean but with symptoms of running rich like sooty exhausts.
The higher pressure fuel injectors spray smaller particles of liquid fuel, which vaporize more completely during their brief time in the combustion chamber.The quicker they move to 350 or 500+ bar GDI, and away from the common 200 bar GDI, the better.
This also allows a higher compression ratio while holding off spark knock.But the better fuel economy isn't just from running lean, as witnessed by the higher torque for the same displacement. Another benefit comes from the fuel evaporating inside the closed cylinder rather than in the ports, so temperatures drop and thermal efficiency goes up.
Diesel fuel is a very different composition from gasoline which results in more soot from diesel. You can't "roll coal" in a gasoline engine unless it's burning about a 5:1 or richer A/F mixture.Diesels always run lean and they make lots of soot.
The soot appears because there is not enough time for all the fuel droplets to fully vaporize.
A nanoscopic particle of fuel will burn down to a tiny cinder.
I find myself adding a couple gallons of e0 91 to the tank during this hot times here in my area. Micro dosing with the Redline Si-1, and doing quick GDi CRC cleaning every 10k. Just did a Wichita and back home to Admire KS today doing 79mph on probably 88+ octane and scored 37mpg on the turnpike. I can honestly say that I feel a better running car when I get the octane slightly higher than 87.Unless you monitor knock sensor, fuel enrichment, timing retard.... you'll never know if your engine is happy with 87. Because of sensors and tuning, most will run on any octane. What is optimum depends on the engine and that is unknown to the majority. I know that my HyundaiKia's were not happy with 87 during the summer. Definitely needed mid or premium to get the response back from the go pedal. Beach or commute traffic, 90+F outside, couple extra passengers.... and go pedal is pathetic on regular.
200bar GDI soot is caused by the small fuel droplets that didn't vaporize. Stuff builds up everywhere. And pedal to the floor will create a soot cloud especially after wife drives for 3-4 months.