Ed,
I've been developing new tri-x (ei 160) a bit longer than the old tri-x. in pyrocat HD 2:2:100, in a Jobo, at 68F, I've been developing for 7min for high contrast subject and 9:30 for low contrast subjects. if I do the math right, that's about 16% longer than the times I used for old tri-x. I print on multi contrast paper.
Take care,
Tom