[pwllms]

What I would like to know is if the 2017 model will include the "cylinder deactivation" feature mentioned in the "Subaru Prominence 20/20" document which outlined the global platform. The document is below:

https://www.fhi.co.jp/english/ir/corporate/pdf/vision_fhi_2014_e.pdf

 

[imprezzive]

I don't think cylinder deactivation was mentioned with the new impreza. Took a look at the document and they didn't really tell us which models will have it. Maybe a performance variant of the impreza will have it later on? I really don't know if the standard models will have it.

 

[pwllms]

If you go to page 13 in that PDF document, it shows cylinder deactivation being implemented sometime after 2016. I've also seen it referenced other places where it says that the global platform will feature cylinder deactivation followed by "Lean Combustion" no later than 2020.

I'm hoping the 2017 impreza engine will have it (cylinder deactivation), but I have yet to find confirmation on any subaru site.

 

[John86]

I can't see a performance variant carrying cylinder deactivation. But on the regular vehicles, heck yeah it makes sense. That'll be great to see and own just for the straight efficiency.

 

[BoxerInside]

What's surprising is they don't already have it and with how long that tech has been around for it should be getting closer and closer to becoming standard. Funny how there's all this talk about hybrids, EV's, green this, green that and all these hippies jumping after it, yet there's still many ways to make gasoline engines much more efficient than they are currently.

 

[SubaHatch]

If you go to page 13 in that PDF document, it shows cylinder deactivation being implemented sometime after 2016. I've also seen it referenced other places where it says that the global platform will feature cylinder deactivation followed by "Lean Combustion" no later than 2020.

I'm hoping the 2017 impreza engine will have it (cylinder deactivation), but I have yet to find confirmation on any subaru site.

Have you called your local Subaru dealership about it? Maybe they'll have some idea about the cylinder deactivation. I assume if it's on the PDF then it'll be in the Impreza but then again, things can change between now and next year.

 

[John86]

What's surprising is they don't already have it and with how long that tech has been around for it should be getting closer and closer to becoming standard. Funny how there's all this talk about hybrids, EV's, green this, green that and all these hippies jumping after it, yet there's still many ways to make gasoline engines much more efficient than they are currently.

I like the way you think.

You're definitely right, we've had cylinder deactivation technology for years. No one ever really utilized it though which is ridiculous when they're all fighting about efficiency.

 

[pwllms]

Have you called your local Subaru dealership about it? Maybe they'll have some idea about the cylinder deactivation. I assume if it's on the PDF then it'll be in the Impreza but then again, things can change between now and next year.

Yes I have spoken to my local dealer. If they do know something beyond what has been released to the public, they aren't saying. I even showed them a copy of that PDF about a year ago when I was looking into getting a 2017 Impreza and the salesman said he never saw that before and he is the head of sales.

One other nugget I came across is below. It says the odder date for the 2017 Impreza is October 3rd. So just a few more days. Hopefully Subaru will release the full specs and PDFs before then.
Subaru (Build Out Final Order Start Up Dates) - Donlen Corporation

 

[SubaHatch]

We really won't know until next month when all the specs are listed on Subaru's site. If the Impreza doesn't come with cylinder deactivation, would you look elsewhere?

 

[GotBoost]

That's literally in 5 days. I doubt we'll be seeing anything like that yet.

 

[pwllms]

We really won't know until next month when all the specs are listed on Subaru's site. If the Impreza doesn't come with cylinder deactivation, would you look elsewhere?

I think that will depend on what the timeline looks like for the implementation of new Boxer engine technologies. I know it will have direct injection, but if it doesn't also include cylinder deactivation and engine start/stop auto shut off, then I will have to wait and see what the 2018 model has to offer.

They also refer to something called "Lean Combustion" in that PDF document, but I haven't anything that explains what that actually is and the perceived gain in MPG.

I plan on buying not leasing, so if I have to wait a few more years for a much more fuel efficient engine, then so be it. Unless my current 97 Plymouth dies before then that is.

 

[GotBoost]

I hate that engine start/stop thing.. highly irritating in my opinion.

 

[SubaHatch]

I tried to look up "Lean Combustion" and it's supposed to reduce throttling losses. Not quite sure how, also reduces the amount of fuel in the fuel/air mixture entering the engine for less emissions.

If you're willing to wait then it's best to wait until all the specs are out and maybe wait for the second batch of cars.

 

[GotBoost]

Probably with an active fuel regulator combined with an adaptive ecm that'll change according to the fuel loss.