Piper J3 - Taylor J2
There is plenty in the various books to show the history from the Taylor factory at Bradford PA to Piper at Lock Haven. "Mr. Piper and his Cubs", is a good one.
The J2 could have been a Taylor machine or a Piper one. The Taylor ones were not completely closed in whereas the Piper J2 was very similar to a J3.
I have flown both, and owned several of them. The Piper J2 had a Continental A-40, 40hp. originally. The engine was not too reliable and had a one piece combined cylinder head on each side, and separate cylinders, whereas the A-65 had separate cylinders with their own cylinder heads. They also had a tail skid on the J2 instead of a tailwheel like the J3. The J3 was a great improvement with the Continental A-65 of 65 hp.
The rudder on the J2 was slightly different and the tailskid was not stearable. The J2 also had a 3 piece windshield instead of the one piece molded one on the J3.
Both fly about the same. get the speed right and it will fly right!!