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+--- Thread: What is a speed shift? (/showthread.php?tid=115)
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- Kaan - 02-28-2004
you gotta make sure you have a rev limiter... cause aparently i dont... or a fuel cut off... well i've only been 500 above red line... so i guess that doesnt count...
and i'm guess a "speed shift" is the reverse of a heal toe shift (aka the blip) without the brake... you use the clutch!
- Eclipsor - 09-29-2006
Disclaimer: I like to bring threads back from the dead.
P.S. Drag racing information follows...
hock: While the phrases "speed shifting" and "power shifting" are used interchangeably most of the time, some people still differentiate between the two. Both phrases have been bastardized and most people define them very vaguely or entirely incorrectly. Neither of the two techniques refer to completely clutchless shifting (at least not today). I'll talk about powershifting, since that seems to be the direction this thread has taken.
The trick is to keep the gas pedal held to the floor while stabbing the clutch pedal and simultaneously shifting into the next gear. Obviously the RPMs will be rising rapidly while the clutch is disengaged, so the stab and shift has to be FAST. If executed improperly, you'll roast your clutch. If you have no power, you'll bog your motor. If you're traction limited, then you'll burn some rubber. If executed properly with a setup that can benefit from a powershift, the clutch will engage and the revs will drop while the motor pulls the car up to speed. If you have the power and traction, and your driveline can handle the stresses of this technique, then you can save a couple tenths per shift. This is especially true for cars with a large turbocharger, as this keeps it spooled up between shifts. You can tell if someone is powershifting at the track when you hear the revs rise during a shift, instead of hearing them drop or even stay constant.
Some people only depress the clutch pedal halfway while popping the shifter into the next gear. This is probably because they're not fast enough to engage the clutch again before the revs shoot through the roof. Failure to fully disengage the clutch puts a ton of heat into the clutch disc and will glaze the pressure plate very quickly. The trick is a quick stab of the clutch. Clutchless shifting in a synchronized transmission is really not a bright idea.
- D_Eclipse9916 - 09-29-2006
This is why I love my dsmlink, no-lift-to-shift feature....muahaha
- Eclipsor - 09-29-2006
D_Eclipse9916 Wrote:This is why I love my dsmlink, no-lift-to-shift feature....muahahaI loved it as well... while it lasted. =P The launch limiter is an excellent feature too.
However, DSMLink's NLTS feature is not exactly the same as a powershift, since it cuts power when the clutch is depressed. It's still great, though.
- D_Eclipse9916 - 09-29-2006
powershift means things to different pepolpe as you said. Clutchless operation of a synchronized transmission is not exatly terrible, there are people who are good enough.
- Eclipsor - 09-29-2006
D_Eclipse9916 Wrote:Clutchless operation of a synchronized transmission is not exatly terrible, there are people who are good enough.It's not about being good enough.
Also, powershift should not mean different things to different people. It means one thing... people just think it means different things.
- .RJ - 09-29-2006
Eclipsor Wrote:It's not about being good enough.
Yeah, its how you stand by your car
:roll:
- Eclipsor - 09-29-2006
.RJ Wrote:Yeah, its how you stand by your carHmm, not really sure what you meant by that, but, you said it yourself...
"A quick way to turn your transmission fluid into a pool of metal shavings?"
I'm assuming you were talking about clutchless shifting. Like I said, it's not about being good enough. Even if you match it perfectly every time, you'll still break your transmission LOOOOONG before you would have if you shifted using the clutch.
- Feersty - 09-29-2006
Eclipsor Wrote:.RJ Wrote:Yeah, its how you stand by your carHmm, not really sure what you meant by that, but, you said it yourself...
Fast and the Furious, man.
- Eclipsor - 09-30-2006
Ah, LOL... I remember now. I didn't pay enough attention to that comedy while I was watching it. Yeah, so you're with me Ryan. Disregard my ignorant post. I need to brush up on my F&F lingo. Heheh.