Tom Hubbard hanged for more then 140 hours, using a noose-style simple hanger; weigths started at 1.8 kg (1 kg = 2.2 lbs), and ended at 2.8 kg. He wrote that gains in length were 3.2 cm (1 inch = 2.54 cm). NOTE: I haven’t re-read this data; you may control it in Tom Hubbard Classics.
Kristian69 used an extender for 968 hours; starting tension was 600-700 grams (450 grams = 1 lbs), final tension 1.5 kg; he had a length gain of 2 cm.
The formula says this :weight elevated to 3.1 factor then multiplied for hours under tension and then divided for 600 (constant) give the length gain expected.
In example : hanging an average weight of 2 kg for 100 hours give: 8.57 (= 2^3.1) X 100/600 = 1.4 cm.
This should be valid in fixed ranges of weight-hours; we can’t expect to gain 140 cm after hanging 2 kg for 10.000 hours :-)
Constant should also be a function of the weight used: it could seems more logical.
As I said, it’s just a play; lot of uniform data are needed for really approaching some weight-time-gains equation.
However, the hypothesis that younger PEers have more difficulties to enlarge penis seems not convincing to me; also, lack of elasticity should not means easier gains, but easier injuries, am I wrong?