See the British Journal of Photography Annual from 1965-1986 or so.

In any event, Paterson Acutol will perform much better on those films
than Beutler will, because Beutler developers compress mid-tones.

 If you are mixing up the 1 gram Beutler, use it full strength. I used
1/2 of the full liter to develop a 120 Pan F using a 1 liter tank.
 If you have the FX-1 formula at hand you will see that 1/2 of a liter
of Beutler is 1 liter of low sulfite FX-1.
 I tried both and found that 1/2 liter of the low sulfite FX-1 was more
suited to Pan F. HP5 and Tri-X may need the more metol Beutler.
 I've not my records at hand but usually shoot for 9 minutes or more.
Use an over size tank if possible and vigorously agitate seldom.
 I liked the results and plan to do a lot more work with the Beutler/
FX-1 types. I think the two are becoming more popular. Photo. Formulary
and now Barry Thorton have the ready-mix. R. Suzuki thinks it great.
He has several variations. I think you can find his article by
searching Google for, fx 1 .                                        Dan