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Discussion Starter · #1 ·
I'm looking for a technical description and pictures/diagrams of the Ascent engine. I've found a few general videos and a few pictures of the entire assembly. I'm looking for something that describes things like the valve train and layout, pics or diagrams of the intake and exhaust headers and layout with the turbo, cooling system, oil system, ignition/electronics, etc... It's gotta be out there somewhere, so if anyone could point be in the right direction I'd appreciate it.

This is my first Subaru so I'm sure there is a lot of stuff most consider common knowledge that I don't know.
 

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2019 Ascent Touring (CWP)
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I can't help you with your request, but I will say that I don't think that this kind of detail in any way represents "common knowledge". You'd likely need to subscribe to the same information source that service providers have to pony up for to get service-level detail.
 

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Discussion Starter · #3 ·
Yeah...maybe common knowledge among the Subie performance aficionados? Here's a description I found that at least covers the big pic, things probably most already know:

"It features all-aluminum heads and block, to reduce weight and allows for more rapid warm-up. The internals include heads with dual overhead cams, driven by a timing chain rather than a belt, actuating 16 valves with variable timing.
It has a total engine displacement of 2,387cc with a 94-millimeter bore and an 86-millimeter stroke. The compression ratio is 10.6:1 which keeps cylinder pressures high for efficiency. It also features a twin-scroll turbocharger."
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I know there are 2018 wrx FSM manual out there you can download for free which contain the same engine architecture as the Ascent
2018 WRX has somewhat similar engine architecture, but a number of things have changed, including some key things, such as piston rod shape, piston shape and design. But, it would be a starting point.
 

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Discussion Starter · #7 ·
Hey. Thanks. My interest right now is more out of curiosity than need. Downloading the Ascent manual looks to be a PITA so I'll hold off on that until I have more of a need to do it. Maybe by then it'll be out there. I'll continue to search the web for info and maybe check out that wrx manual.
 

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Discussion Starter · #8 ·
OK. Here's a question. How is cyclinder intake pressure controlled in these engines? Some earlier and perhaps more primitive turbo charging systems that I'm familiar with had "waste gates" that would control/limit boost by controlling the amount of exhaust allowed to bypass the turbo. Do these engines have waste gates, or do they allow the turbo to run freely and use butterfly valves in the intakes to limit cylinder pressure? I saw a Subaru video that showed individual cylinder intake butterfly valves directing air flow in a way that was necessary for direct injection to work well. I pressume these are also used to control cylinder intake pressure. Is that correct?
 

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Do these engines have waste gates,
We have a mechanical wastegate that's electronically controlled. It is a variable wastegate to bleed off or regulate boost at whatever level necessary.
 

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Discussion Starter · #10 ·
Yeah. I googled "subaru twin scroll turbocharger" pix and see various turbos with integral waste gates that have two poppets, one for each scroll. I presume the Ascent turbo is similar then.
 

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Yeah. I googled "subaru twin scroll turbocharger" pix and see various turbos with integral waste gates that have two poppets, one for each scroll. I presume the Ascent turbo is similar then.
The permutations of the MGT22 are staggering, lol. So many variations.

It was a Garrett MGT22. It's now a Honeywell MGT22. Same turbo.
 

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