My father has a sloow dialup connection, about 33K. His modem is connect to
the phone line via an RJ11 line about 17 ft long.

The RJ11 connection is through a circa 1950 plug type jack in the next
bedroom over.

Two questions:

1: Is the length of the RJ11 line impacting connection speed?

2: Would taking a real line cord from the old block into the other bedroom
speed up his connection?

Thanks much,

Marc