I did some racing this last weekend and a private strip and had a few bad launches and some good launches.
My method is holding the revs around 3000 then when the flag drops, I mash the gas pedal to the floor at the same time I release the clutch. To go from full clutch to no clutch is about 1/2 of a second I'd estimate. So a fast clutch release. By the time the clutch is fully released the rpms are around 5000-5500 and the tires let loose for about 0.8 seconds.
Since the engine can build boost starting around 2800 rpm with load, the quick mashing the pedal to the floor while releasing the clutch builds a psi or two boost in only a quarter of a second. The smooth but quick clutch release doesn't send shock waves down the drivetrain and by full clutch release the full power is delivered to spin the tires a tiny bit.
This was done on a 28F day and a unpreped rough pavement surface. My front tires where at 37psi, and rears where 33psi.
I just cross my fingers my trans lasts long enough for me to save up for a nice 1-4 straight cut gear set.