You can try the NAP FOC 170 gr broadheads I got great arrow flight out to 60 yards with these

 

Try a 150gr Sevr Robusto. I shot them with 18"BEE's in my 355 micro, very accurate out to 50yds

 

That 340 would be very inefficient in my experience with any mechanical, but when you try opening them over 1 1/2 cut blades with the 340 I think you loose efficiency. I would turn to a VPA three balse in my first choice for that weight head. But before I did that, I would stick to 125's and try adding heavier inserts, or adding weight to the inserts to get that same foc you are looking for.

I think any of the Excalibur bows 350 and bellow are at their most efficient big game form, including accuracy, penetration, and reliability when tipped with 1 1/8" to 1 1/4" fixed blade broadheads! The only options I will use in mine in this speed are slick trick standards, Viper Tricks, and VPA 3 Blades. They have proven time and time again to be most accurate and reliable big game heads.

This works for me even my fastest compounds, and the only choices I will use anymore. I used to try everything new, but have found nothing to work better in every bow I own, and has made my life much easier not to mention simple!

 

Might try again to fletch some XX75 2219s in order to get the arrow weight up a bit. My first attempt had too much helical. I was thinking about trying the NAP Quickfletch as I don't have a straight jig clamp to run offset. I do have some 100 grain Wasp fixed blades (1 1/8") that I have not tried yet. Also some 100gr, 1 3/4" , mechanicals that fly great out to 50 yards with the stock quills, but prefer to do fixed blades.
Not much available in 150 grain...

 

The Quickfletch do a nice job on the XX75 shafts but I got the ones with the kicker on the vanes. That was all that was available.
The XX75 2219s hit about 4" lower than the standard quills at 40 yards with the same 150 grain. 60 grains difference in total arrow weight.
With 150 grain Wasp they drop another 4". The standard quills shoot BH and field points together.
It must be that the Quickfletch with kickers spin more and the resistance from the BH slows it a bit.