I'm the weedburner guy with the screen door thing that yellow rose warned you about. I actually agree with him in general, but there's more than one way to get there. You don't need a SoftLoc.
The clutch is a key component that can completely eliminate a torque spike during launch. If you see the nose drop on a manual trans car in 1st gear before the shift, theres probably something to be gained by tuning the clutch.
Here's how the typical drag launch goes with a manual trans...as soon as you dump the clutch, you can hear engine rpm drop. That's the sound of inertia energy exiting the rotating assy, creating a torque spike that's seen smashing the tires. As that torque spike dissipates and the engine starts gaining rpm again, the rear tires bounce back up and the front end drops. Now it's accelerating on engine power alone, without any boost from the torque spike. But it's not accelerating with as much power as it could, as some engine power is being fed back into the rotating assy as it gains rpm. Basically there was a temporary torque boost as rpm dropped, but that boost is paid back in full before the engine reaches it's original launch rpm. If the clutch had slipped just enough to carry the same rpm out until the car was going fast enough to match engine speed, launch would been smoother overall, slightly quicker with less wasted motion, less sensitive to shock settings, and that parts killing torque spike would be completely gone. You don't have to have a SoftLoc to achieve that.
My website explains how I eliminate the torque spike, you can find it here...
ClutchTamer.com
You can also mount a small adjustable damper cylinder behind your throwout fork to achieve the same effect, it's just less convenient to adjust...
http://www.airoil.com/v6/contents/en-us/p28.html
You need to have a clutch with plenty of capacity, but if you are killing parts now you probably already have that. An iron disc is nice, but not an absolute necessity.
Grant
