Direct injection

[Q45tech]

Well it disappeared so I'll start over. and try to recreate the wheel!Note Lexus new dual injection some in intake port and some directly into cylinder [2 injectors per cylinder].

"You can see that there are actually two injectors for each cylinder - the top one is a standard port fuel injector, while the bottom one injects fuel directly into the combustion chamber. The two injection systems are used together to optimize the fueling over the engine's operational envelope.

As described in the January 2006 issue of SAE Automotive Engineering International, the system primarily relies on the port injection system when low engine speeds are combined with high loadings. Under these conditions, a direct injection scheme cannot properly atomize the fuel, and so approximately 60% of the fuel is provided by the port injector. As engine speed increases, the direct injection system takes over more of the fueling responsibility, until eventually it provides 100% of the necessary go-juice. Obviously, there some complex calculations going on to determine the optimum fueling over the engine's operating range, and that has led to over 300 patents being issued to Toyota concerning the design of this system."http://powerlab.mech.okayama-u...3.pdfhttp://www.lavision.de/downloa...1.pdf

Note Toyota has dropped the bucket shim valve lifters and returned to old Q45 type HLA!

I have to look at 200,000 citations back soon

[elwesso]

Tech the link seems to be broken or down...

[CrimsonQ]

404 wooo!

[maxnix]

I've always wonder why the Nissan Direct Injection VK45DD appeared only one year. I like the Lexus solution, but I wonder how other OEM are getting by using only direct injection?

[FarFetched]

Quote »Well it disappeared so I'll start over. and try to recreate the wheel!Note Lexus new dual injection some in intake port and some directly into cylinder [2 injectors per cylinder].[/quote]As we know diesels are more efficient because of higher compressions and more complete fuel burn!The International 7.3 DTI is direct injection engine has been around for many years. It is about time car maker developed strategy to place injectors closer to the combustion chamber!If could only be possible to increase fuel pressure to ~3-5000PSi, atomization wouldn't be a problem in a gasoline engine. 7.3L DTI mid-range RPM fuel pressure ~ (factor 7:1 built in the injector itself) 10.000PSi [enough to cut a birthday cake]. Besides the point that higher fuel pressure designed to overcome much higher compression than in a gas motor. Increasing fuel pressure on a gas engine would help to optimize intake runner design or even eliminate part of it!If by design a gas engine could maintain such fuel pressures, we'd be looking at 30+ MPG on an avarage V-6 engine!I am very interested in seeing such design in a gas motor!Cheers!