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      09-17-2021, 02:37 PM   #83
ntg44
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Quote:
Originally Posted by XutvJet View Post
I'll hold judgement on the power until we start to see the numbers. Sure, they only gave it 3 more hp but power under the curve could be substantial and that is what will make the biggest difference in acceleration.
So many people are saying this, and yet Subaru's own numbers as well as some basic math don't support this.

The official torque curve numbers are exactly the same. 258 lb-ft from 2000-5200. Assuming the torque curve is wider, and 258 lb-ft goes further than that, a reasonable guess is 258 lb ft @ 5500 RPM is 270 HP, only 1 less than the advertised peak HP.

The engine has a 6100 RPM redline, so that only means that torque is falling after the torque peak, just like the previous FA20 engine. Except the FA20 revved to 6700 RPM, although the torque drop off was so significant it probably wasn't worthwhile. With the new engine having a 6100 RPM redline, same torque peak and curve, and nearly nonexistent horsepower bump, this engine is going to have essentially the exact same characteristics as the old engine with the exception of transient response improvements from the revised wastegate. It's a minor improvement at best.

The only other benefit I can see is to have the gear ratios optimized for a 6100 RPM redline, instead of 6700 like the previous generation. Spacing out the gears to take advantage of the mid range would be the only real benefit for acceleration, since you wouldn't have an extra 600 RPM of falling torque and wasted revs, along with suboptimal gearing to go along with it. My estimation is the WRX will have somewhat of a flat HP curve from 5500-6100. Which isn't bad from a technical point of view, but the advantage is in the gearing, if and only if they adjusted the ratios correctly. Gearing for a 6100 RPM redline is different than gearing for 6700 and short shifting at 6100.
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