They make more power(to the crank), but I wouldn't say they are faster then a KA.

dumping the clutch is not the way to do it on street radials, in my opinion.

Next time you go, hold the rpms at like 25-3000, w/e you are comfortable with and slip the clutch out as you gradually increase the throttle input until the clutch is fully engaged and then go full throttle.

Now, I have never ran a 240 at the track, but as far as most cars I have, this has worked well for me.