Milestone achieved - dual injection

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I think Toyota is eschewing turbos in their mainstream lineup for reliablity/durablity concerns. D4-S was first used on several JDM models and the RWD Lexus lineup that isn't an SUV. GDI Lexus models also haven't been getting as gunked up as the Germans as well. Ford is using D4-S in essence in the updated 3.5 Ecoboost. Toyota let Ford use their hybrid patents, and vice-versa for emissions control patents.

Toyota might be a worse cost cutter than VW or GM, since they tend to cost-cut what people will see, feel and touch - the interior. But powertrains, except for a few exceptions is where Toyota tends to focus on.
 
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It says that the car has a "resin cylinder head." What's that?
 
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Compared to the outgoing Corolla, the new model offers more power, higher levels of efficiency, and fewer emissions. The engine is also smaller and lighter than the 1.8-liter engine that it replaces, which effectively lowers the overall center of gravity. As a complement to the upgraded interior, the fresh engine contributes to the overall NVH improvements thanks to a more rigid crankcase, lighter resin cylinder head, and ribbed oil pan.

Helping with the burn is a D-4S fuel injection system, which offers both high-pressure direct injection and low-pressure port fuel injection, adapting the fuel delivery method to better suit the situation at hand. There’s also Dual VVT-i (Variable Valve Timing-intelligence), with VVT-iE (Variable Valve Timing-intelligence by Electric motor) for the intake and VVT-i for the exhaust. The VVT-iE uses a single electric motor to control the valve timing, as opposed to oil pressure on a traditional system.

Final details include a longer stroke, a 13:1 compression ratio, larger valve nip angle, more efficient ports, laser clad valve seat, a higher rate of combustion, high tumble flow, and high intake air flow volume.


Resin head? Pretty high zoot for Toyota.

Electric control on the VVT instead of oil pressure. Interesting. I wonder if it responds faster than modulating oil pressure, or with less control issues.

I wonder if Toyota avoids turbo just on the premise of less parts = less places for failure. And less upfront cost. Pure SWAG--I know turbos can last very long times, it's more of total parts count.
 
Originally Posted By: nap
Originally Posted By: ET16
It says that the car has a "resin cylinder head." What's that?


Recycled carpet?

https://www.autoevolution.com/news/ford-uses-recycled-carpet-for-cylinder-head-covers-33989.html



Not metal. Some sort of high temperature epoxy type substance. I want to see one run 500k before I sign off on the durability. It could be tougher, lighter and more resistant to warping, or it could become brittle, or fail completely when the water pump goes.

The electric VVT I like. Instead of just being based on rpm, the Engine computer can look at throttle position and MAF output to tweak the valve timing.
 
Originally Posted By: ET16
It says that the car has a "resin cylinder head." What's that?

Probably a plastic valve cover. It would make sense as well to dampen the sound of a DI engine.
 
Originally Posted By: E365
The new Ford 1.5 EcoBoost triple has dual injection too.


Also turbo and cylinder deactivation. I wonder how smooth it works just with two cylinders. Trabant?
 
Originally Posted By: nap
Originally Posted By: E365
The new Ford 1.5 EcoBoost triple has dual injection too.


Also turbo and cylinder deactivation. I wonder how smooth it works just with two cylinders. Trabant?




Depends on the system. Mazda’s system activates only when the engine is at cruise and only with light loads. Reports on another forum say it is seamless. You cannot tell if it’s on or not since there is no indicator.
 
Originally Posted By: nap
According to this

https://www.topspeed.com/cars/toyota/2019-toyota-corolla-hatchback-ar180519.html

we'll soon have a dual, port+direct injected engine in an economy car.

Turbo seems to be out of fashion too.

Had that for 12 years or more. The D2S injection from Toyota has been a reliable DI option. Can't wait ( I can, it's a transverse engine) to see what the valves look like after 100k ln my RX.

Edit, oh economy. 3.5L is considered economy in the US, with the big blocks around I guess.
 
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The Valve Cover is made from resin. They claim that it makes the engine about 10 pounds lighter if I remember correctly. The electronic valve timing control is only for the intake cam phaser so that the engine can run on the Atkinson cycle to save fuel. This, in my opinion, is far better than cylinder deactivation because it is very simple and has no extra parts involved. It just uses the electric phaser.
Toyota found that their 1.2 liter turbo engine was not nearly efficient enough for their tastes and that using high compression, D4S, and the VVT-iW (electric intake cam phaser and Atkinson cycle capable) system was far more efficient while also making very similar power. The only downfall is that these engines seem to have a very high power and torque peak. Still, I wouldn't hesitate to own one of the new Corollas. Although the new Camry gets about the same gas mileage and has a real transmission.
 
Originally Posted By: PimTac
Originally Posted By: nap
According to this

https://www.topspeed.com/cars/toyota/2019-toyota-corolla-hatchback-ar180519.html

we'll soon have a dual, port+direct injected engine in an economy car.

Turbo seems to be out of fashion too.





Toyota never really jumped on the turbo bandwagon to begin with.


Right, they don't have the skill to pull it off. Even their new high compression Skyactiv clone engine was recalled weeks after launch for major, critical manufacturing defects (take the hint people). It's all entirely 100% their fault too, and not even for a noble cause. Toyota has brutally stretched themselves in the manforce department (starting 15-20yrs ago), all in the name of greed and grandiose schemes to dominate the market. Like a guy at the bar, totally wasted and zooted up on a couple schlings, the corporate entity felt 'like the greatest, most invincible motehrbuddy to ever walk the earth!! I CAN DO ANYTHING AND THEY'LL STILL BEG TO KISS MY BUTT!! REEEEEEEE!' Yep that brand of wasted arrogance.

Characterizations aside, and with their condition of tumorous corporate growth, Toyota has for decades now been contracting major engineering to various external sources. This is the real reason for getting around more than most, with "joint venturing" with Yamaha, Subaru, BMW, GM, Tesla, Mazda and the rest of them- to fill their own engineering holes and acquire IP from them. The marketing perspective maintains the inverse fairy tale that those companies need Toyota, when Toyota really needs them.

Example, any decent engine they've ever made was essentially a Yamaha- from JZ to GR, 2ZZ to 3S-GE, it's all Yamaha. Basically, all of the GE series and some of the FE series. This also speaks to why Toyota is such a technological laggard, they don't have much of an in-house engineering team (Full-time, inhouse engineering team is a drag on the payroll apparently), and the risks they take with accelerated design cycles and half-baked work from sub-contractors are real threats to the masquerade of 'superiority' that they've been dumping several Billions into maintaining for over 2 decades, and so they tread very lightly with new engineering. It's not that turbos are less reliable, other than in theory, it's just that Toyota feels/knows that they can't do them reliably, or do DI without reverting back to PFI with their clear lack of adeptitude combined with their greed for fat profit margins. The Toyota luddites never seem to remember that there are reliable examples of all of the technologies that they're still scared of.
 
My 5.0L F-150 is dual injected (started with 2018 MY). The 2017+ 2.7 and 3.5L Ecoboost engines are also dual injected. I like that a lot better than just DI.
 
Also, no offence there nap, but I like how retrograding injection technology is a "Milestone" like J.C. really? Or is are we astounded that PFI is now offered in a econobox?
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Slash the BSFC, obliterate the emissions, crank up the thermal efficiency, feature 12-nozzle multistaged piezo- direct injectors with a carefully engineered spray pattern with advanced atomization that can stratify a precisely non-homogenous charge mixture using pressures up to 2500bar..... who cares??! PORT INJECTION IN A CARPBOX?! WOW! THE FUTURE IS NOW!!



what am I reading half of time
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Originally Posted By: wallyuwl
My 5.0L F-150 is dual injected (started with 2018 MY). The 2017+ 2.7 and 3.5L Ecoboost engines are also dual injected. I like that a lot better than just DI.


Yeah a bunch of them are going that route. Toyota set the laziness bar, though.
 
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As I mentioned in the original post, the “milestone” is about the tech being available at econobox price point.

From now on there’s no excuse to having carbon deposits and other ailments in the mid and luxury segments.
 
I agree. There's no excuse for obstructive carbon deposits on any class of current-generation vehicle, tbh. DI, PFI are not exclusive 'high end' techs, installing them both on the same car doesn't change that fact. We as consumers should naturally expect better solutions, rather than cheering stop-gap crutch-moves and developmentally economical technological regression. PFI fuel line pressures are still present in exclusively DI cars (from the tank to the HPFP), so all "dual" fuel injection (it always sound better when you say "dual" or "twin") only requires the addition of a low pressure fuel rail and port injectors. That's a whole lot cheaper, and safer (if you haven't solved the problem yet) than advancing GDI injector tech.
 
Hondas DI system does away with the need for a dual injection path and its redundant injectors and low pressure system.

They place the injector above and behind the intake valves so when they open they get a cleaning wash from the Injector which has 6 holes and compensates for the slightly suboptimal placement by directing the intake charge.



UD
 
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