I've no idea what the correct overall approach might be for LSR, but trying to add roll stiffness by increasing the spring rate(s) is the wrong way to get there. If you need to increase roll stiffness you need to increase the size of the anti-sway bar or shorten it's lever arms. Adding spring rate not only doesn't work, but now your damping is off and the tires will have a harder time following the surface of the track thereby decreasing available traction. That said, it could be that for LSR a spring rate increase is desirable.
If you do remove the front bar and there is a rear bar it needs to come off too. Not removing an existing rear bar when the front is removed will result in a car where the rear wants to pass the front. Probably an undesirable trait in LSR......