The 340 comment was about the bars. I would not put 340 bars in it.
Have you cut the upper bump stops. If the car tops out on the stops,it will essentially KILL any further transfer.
17# in a drag radial on that car is WAY too low. You're killing the sidewall. The sidewall rebounding and poor shock control are likely causing a lot of the issues with the hop as well.
SS springs, rancho 9 ways, 275's at 23#... 1.43-1.45 60's
My friends Cuda goes 1.40's with 275's at 20-22# It's goes 1.34-1.36 on a slick