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Discussion Starter #1
The CVT on my 2017 Impreza works differently than the CVT on my 2014 Forester did. Is this expected?

In the Forester, stomping on the gas to merge onto the interstate, the engine would quickly go to 6000 RPM and stay there until I let up. In the Impreza, it more slowly goes to 6000, then downshifts to 5000 RPM at about 50mph, builds to 6000 at 60, downshifts to 5000 again, and then downshifts again at 65.

I'm surprised by those downshifts.
 

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By no means am I an expert in this field. But when I was researching cars, I had no idea what a cvt is or does. The video "Are CVTs The Best (Fastest) Transmissions?" by Engineering Explained on youtube (sorry I can't post links yet) explains the theory behind CVTs and is pretty understandable to the average joe.

Based on what he says, maybe car is trying to maintain that max HP at the given speed you are going which could explain the downshifting. I'm not 100% on that though.
 

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That's the way the new CVT works. Everyone says it's soooo much better. When you floor the throttle pedal it simulates the discrete gears with a "traditional" automatic. The downshifts you mention are actually up-shifts when the engine revs drop as you go from 1st to 2nd to 3rd as the car speed increases.

A lot of folks (a bunch of whiners in my morning cranky opinion) objected to the old way CVTs would wind up the engine to 6 grand and stay there as the car then builds speed out of sync with the engine speed sound. I will admit that with my 05 Mercury, at first, it would give me the impression of a manual transmission with a slipping clutch and would be accompanied by the associated stomach acid of a anticipated $1000+ repair bill. How much is a new clutch job these days anyway? It helps if your engine sounds happy when it revs up - the Mercury did not - even a stock Impreza is much better.

The original CVT solution for me was to imagine yourself in an attack helicopter (or a P51 Mustang - if you're old enough or watch enough History Channel to know what that is). You have a time lag as the rotors/propellers dig into the air; that bug on the windshield is your Sidewinder missile aiming pipper (or the P51 gunsight) lining up nicely for the Chevy Suburban tailpipe on the horizon. Whooosssshhh or Tat tat tat tat tat tat ....

Much better feeling - just don't tell your shrink about doing it in your Forester or you might be meeting the guys in white that have a coat for you with really long sleeves. Don't do it out load in front of the kids either. Tell the spouse they are your backseater/RIO/co-pilot and to check for bogey's on your six. If the kids are back there have the spouse check for boogers on you six as well.
 

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The 17 Impreza CVT is designed to mimic a traditional transmission. It's not one of my favorite parts of the car, but I'm learning to deal with it. I have an 11 Outback which has a more expected CVT feel. I kind of feel like a CVT that fakes the a shift is like eating Tofurky. Either it's meat to it's not. Don't try to be something that you're not.
 

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The CVT on my 2017 Impreza works differently than the CVT on my 2014 Forester did. Is this expected?

In the Forester, stomping on the gas to merge onto the interstate, the engine would quickly go to 6000 RPM and stay there until I let up. In the Impreza, it more slowly goes to 6000, then downshifts to 5000 RPM at about 50mph, builds to 6000 at 60, downshifts to 5000 again, and then downshifts again at 65.

I'm surprised by those downshifts.
I have the Sport & this is my first car with CVT but I absolutely love it. Last car (4G Eclipse) had a 4 speed automatic transmission & it sucked. Merging into highway traffic this car is a beast once you floor it & watch the RPM's almost hit the red zone. There is so much power in this car some folks haven't even encountered yet. Keep your foot way down on the gas when merging you should see a difference.
 

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Just noticed while driving tonight, that you can operate the paddle shifters while in "D". The "gear" number appears & reverts back to "D" after about 15 seconds of not using the paddle shifters. Has anyone noticed this?
 

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Just noticed while driving tonight, that you can operate the paddle shifters while in "D". The "gear" number appears & reverts back to "D" after about 15 seconds of not using the paddle shifters. Has anyone noticed this?
yeap, noticed this. seems to switch back to D in mild acceleration, but if you are off the peddle and going downhill, you can downshift and it holds it in gear alot longer, making it like a engine brake, like you used to do in a manual car :). Hard acceleration and paddle while in D i have not tried yet.
 

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Just noticed while driving tonight, that you can operate the paddle shifters while in "D". The "gear" number appears & reverts back to "D" after about 15 seconds of not using the paddle shifters. Has anyone noticed this?
Normal. Many cars with paddle shifters have that now. In the Subaru, depending if you have your foot on the accelerator or brake, it will keep the gears longer (engine breaking when slowing down, downhill) or shift back to 'D' and upshift if you accelerate. It's great when passing or accelerating on the freeway, and then let the car shift back to fully auto.
 

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Discussion Starter #10
Just seems odd to me to take something like a CVT design, which among its features allows the engine to operate at its maximum power, and impose skeuomorphic programming on it to mimic shifts. I suppose its not very much, but when you are calling on the car to accelerate at its maximum, not only do you artificially reduce the output but you introduce the inefficiency of changing engine speeds. I thought the point of a CVT was to allow the engine to operate at maximum efficiency, but override that when maximum output was required.

Of course, in the lizard part of my brain I'm thinking that the car is accelerating at a maximum rate when the engine is redlined, when that might be at a different RPM. But still, it would be the same RPM.
 
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