new dxt want more speed

[demonseed34]

I have a dxt 29 in draw and 50-60 lb.it has a rip cord arrow rest and i shoot grimreaper razor cut broad heads. I would like to know the shortest arrow i could shoot.:banghead:

 

[auschip]

I always heard the shortest arrow would be 1 inch over your draw length. If you want more speed the easiest way would be to increase your draw weight.

 

[demonseed34]

i am shooting carbon express terminator 6075 at 31 inchs wich are 9.1 grains per inch i was looking at going to the maxima 250 which are 7.5 grains per inch i was told that with a drop away arrow rest that i could shoot an arrow that was the same at the draw length but I don't know alot about arrow selections. I know how to set up bows, and maintain them, but i don't know much more. I was also told the the 31 inch arrow has the spine in the wrong area. Can you elaberate on this?