Does the Pentastar, being paired with the 8 speed trani, make better performance? It sure seems better than my JK when I drive e my wife's Grand Cherokee.You’re basing that on what? You didn’t even get the MAX torque RPM correct (for old or new) and those are published numbers, sounds like a lot of mythology on your part, so why would the rest be any more of an accurate reflection of the situation?
Torque curve on the Old Pentastar shows 96% of the torque by 2K RPM, so another 4% / 10lbft for 2,800 more RPM means very little.
With the new Pentastar the benefits are for earlier power delivery (by about 300 RPM) and better fuel efficiency, so things are improved not diminished in the new PUG refresh in the JL.
Turbos don’t always produce more torque down low, especially for small displacement turbos, it depends heavily on how they are tuned and what their focus is... speaking of which, look at the Ford Focus ST’s torque curve, that’s not early on, but well after 2K, and it’s also early decay, neither of which is great for power delivery or highway performance, but that’s because it’s meant for economy not performance, which may be the focus of the JL’s turbo too.
Slow building torque curve in 2.0L turbo in the Focus, max may be sooner, but it takes longer to get 75% at 2K RPM because it’s a gradual peak, not early on then flat curve.
The advantage of the Pentastar is we have reference curves for the prior design, and the new one is torquier. There is no reference for this 2.0T which won’t even match Alfa numbers, so making a claim about 2.0T without removing the effects of the BSG is pretty spurious. It depends heavily on how FCA positioned the tune, and if they bult-in reliance on the BSG for down low.
Also throttle response will remain a major issue for the 2.0T as seen in the early reviews mention of lag, and only pre-charging will help reduce it, which isn’t helpful on the trail, nor is it how most people drive.