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Old 02-27-2016, 01:48 PM   #5 (permalink)
ever_green
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Join Date: May 2011
Location: Toronto
Posts: 263

Blueberry - '17 Mazda Mazda3 GS
90 day: 32.56 mpg (US)

EVO - '08 Mitsubishi Evolution MR
90 day: 23.82 mpg (US)
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Quote:
Originally Posted by ksa8907 View Post
Fyi, late intake valve closing is a popular strategy to reduce effective displacement for highway driving.

I'll seach the web, but how exactly is subaru controlling lift? Is it continuously variable or are there specific settings?
link for: Subaru: i-Active Valve Lift System (AVLS)

The camshafts on an AVLS-equipped engine have specially designed lobes for intake valves. They feature two different cam profiles:
1. A low/mid-lift profile
2. A high-lift profile
Which cam profile is utilized is regulated by the Engine Control Module (ECM) computer. The AVLS-equipped Subaru engines use oil pressure generated by the engine to activate the different valve lift settings.

The intake valve timings from service manual are as follows:
Low speed Open BTDC 0 Close ABDC –10
High speed Open BTDC 14 Close ABDC 62

from a calculator:
Your low cam has an Overlap of 14.00 degrees and has in Intake Duration of 170.00 degrees. The Exhaust Duration is 224.00 degrees. Your Lobe Separation Angle is 91.50 degrees.

Your high cam has an Overlap of 28.00 degrees and has in Intake Duration of 256.00 degrees. The Exhaust Duration is 224.00 degrees. Your Lobe Separation Angle is 106.00 degrees.

Last edited by ever_green; 02-27-2016 at 02:01 PM..
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