Z06Vette.com - Corvette Z06 Forum - What's diff between powershifting and speed shifting?

Manatee · 06-25-2002, 06:20 PM

Dummy here - Reading the Atlanta Dragway post, what's the difference, advantages, disadvantages between powershifting and speedshifting?

ZO6LS6 · 06-25-2002, 07:01 PM

Tee',
Powershifting is NOT lifting your accelerator pedal off the floor, when shifting.....
Speedshifting, is just shifting as fast as you can, AND lifting.........
Advantage on PS is quicker ET's......Disadvantages is more wear and tear, on cluches, driveline in general.....
SS, is usually a tad slower( on the ET's), but, will allow tyour driveline to live a while longer...........

the rave · 06-25-2002, 07:47 PM

assuming you are an accomplished wrench with your own lift n tools, about $3500 of wasted (ie need to be replaced) parts every 6 months or so...

powershifter, ranger et al, no need to reply, jus funnin widja..

OpticZ06 · 06-25-2002, 07:53 PM

Why lift when you can stand on the pedal and DRIVE IT LIKE YOU STOLE IT!!!!

Manatee · 06-25-2002, 09:42 PM

Thanks for the explanation. How much quicker e.t. do you get powershifting? Tenth of a second??

Is anyone good enough to shift while drag racing without using the clutch? My brother showed me this trick ONCE at a very LOW speed with an old car.

PowerShifter · 06-25-2002, 10:01 PM

Quote:

Originally posted by Manatee
Thanks for the explanation. How much quicker e.t. do you get powershifting? Tenth of a second??

Is anyone good enough to shift while drag racing without using the clutch? My brother showed me this trick ONCE at a very LOW speed with an old car.

Shifting without the clutch can't be done safely at full power because of the syncronizer design. It can easely be done at low throtle, but why would you want to if the clutch is working? Power shifting depending on the hook the track has, can be slower to .15 faster depending on the speed shift your comparing. IMO Ric

**MikesZ06** · 06-25-2002, 10:15 PM

Have always been a speed shifter. Powershifting must take some practice. A week ago last Friday, I screwed up what probably would have been my best time of the night. 1.901 60' (good for me), 5.298 330ft. 7.912 1/8, tried to power shift and missed 3rd, coasted to the line. Didn't try to powershift the rest of the afternoon.

ZO6/Les · 06-28-2002, 11:51 AM

I have read that a good powershifter can improve E/T .1-.2 over a good speed shifter, all things being equal. I can and have powershifted, but not often due to driveline shock. In my experience it is worth about .10 E/T and 1.5 MPH, but I can speed shift pretty darn fast (I have been told my car sounds like an automatic when I race).

I do not recommend powershifting for the novice.

Les

Quote:

Originally posted by Manatee
Thanks for the explanation. How much quicker e.t. do you get powershifting? Tenth of a second??

Is anyone good enough to shift while drag racing without using the clutch? My brother showed me this trick ONCE at a very LOW speed with an old car.

george · 06-28-2002, 04:56 PM

Pedal to the metal w/out lifting, just shifting with the clutch. Back in the late 60's when I started racing we used to find the engage and disengage area of the clutch and installed a block of wood to the clutch pedal so it would hit the floor and it didn't move any further then necessary. Hot rod magazine idea.

I don't recommend this as I lunched a few big blocks that way. Also what's the big rush, if your running anywhere in the 12's with a stock Z06 you have already proved you have the fastest stock production corvette ever made. Better to be safe then experiment as we did and have the track shut down because you blew up something. Stay safe.

ElectronZ06 · 06-29-2002, 07:08 AM

Powershifting really tears the drivetrain. Ive seen clutches from cars that were frequently powershifted. Burns and scores all over the place. Eventually your clutch will start to "chatter" under normal driving. At that point you will need a new (or at the very least resufaced) flywheel.

EB_Z · 07-01-2002, 09:19 AM

It was my understanding that when you shift w/o the using the clutch pedal, and not lifting off the gas, that was powershifting.

Speedshifting was not lifting off the gas, but quickly jabbing the clutch pedal as you shift was speed shifting.

Shifting normally, lifting off the gas and using the clutch, is called granny shifting.

In my LT1 F-body, I used to speed shift the 1-2 and the 3-4 shift. I never speed shifted the 2-3 shift since I would occasionally miss the gate, so didn't want to risk nailing the rev limiter.

In my LS1 F-body, I would just speed shift the 3-4, since the motor revs so quickly in 1st, and the stock tach could not keep up, I would occasionally hit the rev limiter between shifts.

In my LT1 F-body, a good run with the 2 speed shifts would get me between .15 and .2 quicker than a good run granny shifting. I never got consistent enough in the LS1 F-body to tell the difference tho.

I never had a problem with my clutch or anything on either of those cars, but I didn't go to the drags every weekend, YMMV.

You can also practice speed shifting at normal highway speeds at part throttle to get the technique down.

EB_Z