i was bored and decided to explain what the term "double clutching" is meant to describe. double clutching technically refers to using ur clutch to pop out of gear, and again to pop it in when downshifting for cars with synchos, but people toss it arount to describe a streetracing term meant to describe a move that people do when racing (especially honduhs and their high reving/no torque combo).
During a launch, the launch speed is normally around 3k. Well on some cars there is very little tourque being produces untill about 2-3k more. while in this lower area, with the go pedal on the floor still in 1st gear, you proceed to tap the clutch just enough so that it very quickly partially disengages and engages, causing the engine to rev up during a short moment so that when your clutch engages again you eiter get a slight wheel spin allowing for the engine to reach its torque curvequicker and thus get faster launces. this technique only works if you have experience with it, because done wrong it will mess launch by either making a massive burnout or making your clutch slip too much resulting in slower launches.
This does NOT work with cars that get most of their torque at low rpms. It helps turbo cars to jump from the turbo lag zone. This is fairly hard to do though, as it usually results in masive whistling burnouts.
i used to do this all the time on my 89 civic hb. It had a civic dx motor/ tranny swap, a stage 3 clutch, port and polish, 3 angle valbe job, presuure regulator, short shifter bbtb. it was allso stripped all the way down, only one seat aluminum dash, event the exterior trim and metal bumpers under bumper covers were taken off. i was able to beat si's gsr all kinds of ish, even my own accent on juice

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