If you dont want to take the chance at breaking something, dont go. Otherwise take it up to 4k then when the yellow light on the tree goes on, start to slip out the clutch then GO. You can adjust your rpms your launching at based on how it went the prior run. IF you bog you may want to take it up a bit higher or you may not be slipping it right. Practice makes perfect, but dragging is very abusive on your car.