Yes, very helpful. Standard HW77 spring has 35 coils over 253mm, whereas Titan no. 1 (listed as replacement for HW77) has 31 coils over 280mm. Hard work getting that in without cutting it down!
BSA Meteor standard has 37 coils over 276mm, but the Titan "equivalent" (No. 6) has 39 coils over 341mm. Now that was a bugger to install...... had to cut 30mm off it and collapse a couple of coils!