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Old 08-25-2021, 02:33 PM   #40
ZDan
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Quote:
Originally Posted by stilesg57 View Post
Regarding the tq curve: how is that emphasized when there's still a dip (albeit a smaller one) and even it's not a full 20% gain either? Just seems like this engine is all-around less efficient than the outgoing FA20.
You shouldn't just go with PEAK power and PEAK torque alone.

The earlier engine sacrifices power and torque throughout the range for a couple of peaks over limited rpm ranges. Likely the new engine's cams have a bit less duration and overlap, hence broader less peaky power curve.

At hp *peak* of 7000rpm, the new 2.4 indeed only makes 11% more power vs. the 2.0 and not 20% more as displacement would suggest, all else equal. And the new 2.4's *peak* torque is only 18% more vs. the old 2.0's *peak* torque (close to but not quite 20%).

However, if you look at power and torque at the old engine's torque dip around 4000rpm, the new engine is making about 38% more power and torque there.

On average you're going to see ~20% more power and torque throughout the powerband. The peaks have been rounded off a bit, but the midrange trough has been massively filled-in. For sure they could have kept the same amount of peakiness and same power/liter, but at the expense of midrange. I would bet that actual overall performance is the same, but without the lull in the midrange.

Here's my plot of rwhp/torque of 2022 (scaled based on the dashboard readout) vs. 2017:
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