what is it? do i need to do it? and why?
I have heard otherwise. Back in the day with straight cut trannys, no synchros, people powershifted without the clutch. You are right though, using the clutch lightly but keeping your foot fully crammed IS poweshifting...but by getting into the semantics of it, TRUE powershifting is just slamming the gears without the clutch hence the "power" needed to do it by the driver. Some people do it well and are successful. I havn't lol...but I know it works. What we are talking about is more less "speed shifting." You have to be fast to do this without missing gears or smoking your clutch.firemanfrank said:POWERSHIFTING IS:
Making upshifts while keeping the ACCELERATOR PEDAL FULLY DEPRESSED while QUICKLY USING YOUR CLUTCH for each one of those upshifts.
"power shifting", "speed shifting", "clutchless shifting" ...kenpokid said:I have heard otherwise ... TRUE powershifting is just slamming the gears without the clutch hence the "power" needed to do it by the driver.
You cannot powershift a stock trans without using the clutch. You wont be able to get it out of gear unless you let off the gas.
Powershifting is simple. Never let off the gas pedal. Hold it to the floor the entire time. When its time to shift have some pressure on the shifter aimed for the next gear and stab the clutch with your foot.
Hopefully by the time you let out the clutch it will be in the next gear. Thats how you powershift.
And what I think is the best post of them all ...critter
I have been driving for about 50 years, and I have never heard anyone call clutchless shifting, "powershifting".
The only clutchless shifting I have ever done or seen done is with a pro shifted transmission (and that includes the muscle car glory days).
You may get it out of gear without a clutch, but you will never get it in the next gear leaving it on the mat.
Powershifting: Shifting "with" the clutch under continous WOT.
Speedshifting: Letting off the throttle for the split second it takes to push in the clutch and hit the next gear.
Granny shifting: Shifting out of the powerband, at lower than optimum rpms, letting off the throttle for the shifts
Shifting without the clutch: A good way to a BAD day!!!!
alright, agreed[thumb]firemanfrank said:"power shifting", "speed shifting", "clutchless shifting" ...
The terms go on and on! 
Well, I Googled the phrase "power shifting", and after almost an hour I have found that there is no real consensus (one way or another) as to what the term "power shifting" means.
I think the only way that we'll ever find out the "true" definition of "power shifting" is to ask an automotive historian/journalist. Otherwise, the threads about what this means ...
goes on ... 
and on ... 
That having been said, here are some interesting posts from LS1TECH on "power shifting":
And what I think is the best post of them all ...