We have a 1.3L in a 2023 TB ACTIV AWD.
I'm an old school mechanic. I remember when we thought a 140hp in a Chevy 4 banger was big HP.
Now a 3 banger with 155 HP.
We drive in 4-8,000 ft in elevation. I very impressed with the performance.
I ordered a set of BFG KO2 LT 225x65x17.
There in so I'm going to spend the summer in the Nevada back country.

 

There are likely many variables. As you pointed out there is only an 8 ci difference between engines which isn't enough to create the difference in hp/tq or the much lower rpm band on the 1.3, so the turbo size or design could be different. Other possibilities are the camshafts could be more aggressive in the 1.3 and there's also wastegate opening pressures (does the 1.3 build more pressure or do it faster than the 1.2)?

 

I have wondered about that. Tech specs say that the 1.3 is actually 1341 cc, which makes it 8.6 cubic inches larger than the 1.2. With the torque coming on at a lot less RPM, I am wondering if there is some major difference in the turbo setup, or maybe there is some other factor I haven't looked at.

 

The 1.3 is a much better engine than the 1.2 even though it's almost the same size. The 1.3 not only makes more hp/tq, but it also has full torque available at 1500 rpm vs 2400 rpm for the 1.2, so it's more efficient too.