I have this kit with 16X45 gears and it gets about 45 with a 14 bing and a boss. I would definitely try the 16 tooth front if I were you. It still revs up nice and I doubt the low end would be that much worse.
You will definitely have to do some major clutch work too. Right now I have a two shoe with PAZ springs tightened as far as they will go. Even with this it still doesn't seem like the motor has enough power to rev up before the clutch grabs. I would recommend getting a three shoe with paz springs or lightening the two shoe.
This kit really is solid once you figure out the low end. Tons of fun in the midrange and revs to the moon. Seems like with a 16 phgb and all that porting you should be going faster but what do I know.