Processing Tri X 400 in HC 110

I usually shoot TMAX or Delta, but I've been given a box of Tri X to play with. I usually process in a small tank with HC110 dilution B. My HC110 data sheet say 7.5 mins @ 68f, as does the TRI X data sheet, but the Kodak processing chart says 3.5 mins. I've checked that I'm looking at the times for the new TRI X.

Is this a typo on the chart? 3.5 minutes seems way too short. If this figure is accurate, would I be better off using dilution H and doubling the time?

Many thanks

Actually, just found an answer to this one elsewhere on the forum. This place is a goldmine!

I have studied this combo for a while, and these are the results that I found:
Film: TX400, 35 mm.
EI 200
Pre-washed: Water, during 1 minute of constant agitation.
Developer: HC110 (E- 1:47)
Developed two rolls of film, continuous agitation during the first 30 seconds, and then 5 times each 30 seconds.
Time of developing: 6 minutes.
Temperature: 20ªC.
Stop bath: Kodak Max Stop, 1:15, and 1 minute with constant agitation.
Fixer bath: Tetenal, 1:9, 5 minutes. The first minute with continue agitation, and then 5 times each 30 seconds.
Results:
After having taken pictures of a Kodak grey card, I have found the following relative densities:
Zone 8: 1,25
Zone 5: 0,68
Zone 1: 0,10
These densities have been measured with my RH Designs Analyzer Pro.
Theoretically, if you work with a condenser enlarger, like my case, a good exposed and developed film should has the following relative densities: ZI: 0.08 - 0.11 / ZV: 0.60 - 0.70 / ZVIII: 1.15 - 1.25.
I think TX400, EI200, HC110, 1:47 (E), 6 minutes, 20ºC is OK.

we use the combo at school all the time, 6 to 6.30 minutes depending on the students equipment, and will Kodak ever correct that issue with the times. Someplace here there are a lot of threads about that issue, etc. etc. etc. Glad you found some of them.