"Taiwan Black" did pretty well for me. It was a strong climber, and had light green pods that were longer & thinner than most of the yardlongs I've grown. They were about 24" long at harvest stage, and borne in large numbers. It was also fairly early; only another black seeded variety (this one with dark green pods) was faster.

The pod quality deteriorated very rapidly, though, when temps rose (only to the upper 80's here) and the ground dried out. I had to pick them at a much smaller diameter than usual, or they quickly became fibrous. Provided that the seed you planted is in fact TB, the combination of heat stress & water stress might be causing the stunted pods.

The climbing (or lack thereof) could be another issue, especially if plastic (or plastic coated) supports were used. Yardlongs don't seem to like to climb synthetic materials.

Thank you zeedman.
I assume these will be good as a dried bean or for seeds.
The pods are light green and I have them climbing on my grandson's old swingset.
The only other yardlong I'm growing is Chinese Red Noodle.
They aren't climbing well either on bamboo canes.
What do you use for them to climb on?

Ruth, in my experience, cotton string and sisal baling twine work the best as supports. Rusted wire fencing also works OK; I've had good results with concrete reenforcing wire, which is ungalvanized & weathers to a rough finish suitable for twiners to grip. I've tried bamboo as well, and was unhappy with it... the vines started to climb, but slipped down in windy conditions.

Sadly, I do not think the seed will be suitable for use as dried beans, at least not without considerable processing. There is a thin membrane which sticks to the seeds, and it is quite tenacious. The flavor is nothing special, so IMO, it's not worth the effort.

The CRN seems to thrive in the heat, so given enough water, it should do better than the TB. Water really seems to be the key to good yardlongs. In fact, it's almost hard to give them too much water... under the record heavy rains we experienced here last year, the Red Noodle beans produced my best crop ever. In your heat, I'd recommend mulching around the plants to conserve moisture.