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This is my first car with a turbo (or cvt even).
Is there an RPM range where the turbo kicks in and can you feel it?

Thanks!
 

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Since the engine makes full 277 lb-ft of torque at 2000 RPM, I'd venture that the turbo kicks in at that speed or even a little lower. In other words, boost is happeing most of the time unless your steadily cruising or crawling around at very low speeds. Normal acceleration from a stop will require boost, unless you deliberately try to drive like your grandma's grandma.

It can be felt and even heard if you're trying to notice it.
 

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Well that might explain some things if full boost is 2k or below. The thing barely accelerates below 1,800.
 

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And I'd argue if you can hear it. It doesn't sound like any turbo I have ever heard. I wouldn't have even known it had one unless I looked at the specs.
 

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The turbo is powered by exhaust. Press gas pedal, exhaust is generated, turbo starts to spin, more air and fuel is pushed into the engine, power increases. This starts to happen right off idle and you can feel it when starting from a stop. Press the pedal and a second or two later you feel the turbo kick in. Once under way, the turbo is spinning and the ECU controls the throttle plates, fuel, and turbo waste gate to provide smooth power response. I haven't heard turbo chargers in any of the modern turbo cars I've driven.
 

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Turn your radio and hvac off and anything else that can make any noise in the cabin. Listen closely after you accelerate fairly hard then completely let off the gas. Doing so, especially when outside temperature is between 40-60°F, I can hear the little whirr of our little turbo. Imagine the turbo noise that a big turbo diesel truck makes, and scale that sound WAY down. To me it sounds like it’s coming from the engine compartment forward of the glove box.
 

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The turbo is powered by exhaust. Press gas pedal, exhaust is generated, turbo starts to spin, more air and fuel is pushed into the engine, power increases. This starts to happen right off idle and you can feel it when starting from a stop. Press the pedal and a second or two later you feel the turbo kick in. Once under way, the turbo is spinning and the ECU controls the throttle plates, fuel, and turbo waste gate to provide smooth power response. I haven't heard turbo chargers in any of the modern turbo cars I've driven.
WRX turbo is plain as day when it's fully engaged, it's also obvious when the boost starts to start.
 

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This is my first car with a turbo (or cvt even).
Is there an RPM range where the turbo kicks in and can you feel it?

Thanks!
Oh, you are going to feel it in your wallet, mostly!!

You know it kicks in when you are displaying the instant mpg. You push the throttle and you see how it jumps down from the twenties to 5.0 mpg... as you feel the horses pulling your car.
Other than that, you don't need to feel it, or hear it. It's always there in the shadows, quietly working for you. In the past you could feel the lag, you pressed the gas and the car took a short second or so to start pulling hard. On the Ascent I feel near zero lag, this is helped by the CVT, which uses the gear ratio to quickly raise the rpms, getting more exhaust air fast to help spool that turbo.
 

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The refinement of turbocharged engine technology is pretty amazing over the past 20 years or so- the torque characteristics in a modern small displacement turbo engine are nearly indistinguishable from a V8 or large v6 from just a few years back. In the past 20 years, we've gone from needing mandatory cool-down periods, premium fuel, and more frequent oil changes to needing nothing special in a turbo engine.

I am absolutely amazed by the torque available at such low engine speeds in the ascent and my f pace, and to a lesser extent, in my Lincoln MKZ. I honestly don't miss a larger displacement engine at all in these cars (okay, I'm lying a little bit here, I do wish I would have sprung for the 500+ hp F pace svr). I do wish the Subaru got better gas mileage, but my other cars get excellent mileage, and by this point the reliability of a turbo motor is pretty much a non-issue.
 

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WRX turbo is plain as day when it's fully engaged, it's also obvious when the boost starts to start.
While we have a bigger turbo, ours is mounted in front of and below the engine, so, the sound is muffled.

And, since our wastegate is variable, blow off events are more subdued, because it rarely does a full dump.

If you watch me taking a 30° incline up a rutted rocky trail in this video, you can hear the turbo and the wastegate a lot clearer, since I'm really making it work.

I couldn't stay on the gas like suggested, because I'd have lurched through them as all 277 lb-ft of torque engaged. I think they forgot it wasn't a NA motor. ?

 

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And I'd argue if you can hear it. It doesn't sound like any turbo I have ever heard. I wouldn't have even known it had one unless I looked at the specs.
I think for this particular vehicle, this was Subaru's goal. The Ascent isn't a WRX, it's a vehicle that appeals to a mostly different demographic. The turbo in my old Nissan 240sx with the JDM SR20DET was quite a bit more raucous as well, and required higher octane fuel, and got that little RWD beast runnin like a scalded cat :D These days I'm lookin for something a bit more sedate, but still with enough get up and go when I need it. The Ascent has so far fit the bill, and for such a big beast gets decent MPGs.
 

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The surest sign that the turbo has kicked in fully is that sucking sound you hear through the fuel line from the gas tank... :) :D . You know, kinda like that sound a straw makes when you get to the bottom of the milkshake...
 

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There are two big reasons why you won't 'notice' the noise or power of the turbo on the Ascent.

1.) Most of the turbo (spool) noise you hear comes pre-turbo. The plastic intake is designed to be quiet, more so than any turbo car I've seen to be honest. If you were to replace that plastic/rubber setup with aluminum piping and an open air element, you'd notice a lot more noise. (This would be an awful idea).
@Robert.Mauro mentioned the other aspect of this with the variable wastegate not hearing the turbo dump. You're not going to get that Supra full dump at every shift that can be heard 100 yards away.

2.) A twin-scroll turbo does a good job of trying to pretend like it's not there. Turbo lag is the reason why you feel the turbo in the first place. The twin scroll is designed to essentially get rid of turbo lag (among other things) and it does a really good job at that. The power is sorta always there. There is virtually zero turbo lag on the Ascent, which means you never get that sudden onset of power feeling that you'll get with most turbo cars.


Here's how you know the turbo IS working. The Ascent is a 4500lb SUV that has a 4cylinder under the hood and it doesn't feel like a slug.
 

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The surest sign that the turbo has kicked in fully is that sucking sound you hear through the fuel line from the gas tank... :) :D . You know, kinda like that sound a straw makes when you get to the bottom of the milkshake...
...and from your wallet. :ROFLMAO:

But, yeah, I both love that sound and hear it waaaay too often. Beastly amount of air being dragged in and the DI system ramping up fuel into the engine.
 

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Turbos need a switch like traction control. I'd turn it off most of the time....lol
 

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Turbos need a switch like traction control. I'd turn it off most of the time....lol
For a heavier vehicle like the Ascent that might not work very well, unfortunately, given the smaller displacement engine. Even for a very light foot driver like me, I suspect I'd seriously notice the need for folks to push the back of the vehicle to get it moving. :D
 

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WRX doesn't equate fart can exaust. We currently have a WRX, Forester and Ascent....with also previously having an Outback. Not sure what demographic is implied, but I guarantee we don't fit it ;)
 
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