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-   -   Sequential Shifter (https://www.6speedonline.com/forums/gt3-gt2/180271-sequential-shifter.html)

speedyellow4 07-28-2009 11:05 PM

Sequential Shifter
 
Can somebody give me a dummy's explanation of what a sequential shifter does and its value. I've got basic car knowledge but things go over my head quickly. Thanks!

NorthVan 07-28-2009 11:18 PM

You can do no lift upshifting, as soon as your hand touches the shifter, the computer cuts the gas and you push forward and the car will shift to the next gear. You still need to use the clutch and heel toe for down shifting (by pulling back on the shifter).

GMG and FBL sells conversion kits.

mobonic 07-29-2009 12:18 AM

Aw... so you still have to use the clutch, but inly for downshifting.

mousecatcher 07-29-2009 02:21 PM


Originally Posted by NorthVan997C2S (Post 2479657)
You can do no lift upshifting.

Yes, that's a feature of a sequential gearbox but it isn't because of the sequential mechanism. H-pattern gearboxes (e.g. old MK9s that have been around forever) can no-lift shift. It is having dog rings that enables no-lift shift.

mousecatcher 07-29-2009 02:22 PM


Originally Posted by mobonic (Post 2479700)
Aw... so you still have to use the clutch, but inly for downshifting.

nope. again, due to dog rings, you do not have to use the clutch period. nothing to do with the sequential mechanism.

mousecatcher 07-29-2009 02:26 PM


Originally Posted by speedyellow4 (Post 2479639)
Can somebody give me a dummy's explanation of what a sequential shifter does and its value. I've got basic car knowledge but things go over my head quickly. Thanks!

http://auto.howstuffworks.com/sequential-gearbox.htm (easily found by google) is a great description of a sequential gearbox and its benefits.

Note that the conversion kits mentioned here only replicate the shift action and do not provide most of the benefits of an actual sequential gearbox, and they actually complicate the shifter mechanism (some kits can be unreliable). IOW, rice.

Targa Tim 07-29-2009 04:04 PM

sounds like PDK is easier.:D

777vegasviper 07-29-2009 04:14 PM


Originally Posted by mousecatcher (Post 2480327)
nope. again, due to dog rings, you do not have to use the clutch period. nothing to do with the sequential mechanism.


in a sequential gearbox you do need to use the clutch in engaging first gear and reverse.

Upshifts can then be clutchless, so can downshifts (requires a lot more skill than clutchless upshifting).

i have a holinger sequential in my viper, speaking from experience

PJS 07-29-2009 04:59 PM


Originally Posted by 777vegasviper (Post 2480480)
i have a holinger sequential in my viper, speaking from experience

In other words... thread OWNAGE :D

(rep point for vegasviper)

mousecatcher 07-29-2009 07:24 PM


Originally Posted by 777vegasviper (Post 2480480)
in a sequential gearbox you do need to use the clutch in engaging first gear and reverse.

sure, when stopped and engaging any gear you need to use the clutch of course, and again this has nothing to do with the sequential mechanism.

Monaco 07-29-2009 09:18 PM

I don't see the point to those expensive gearboxes when manual gearboxes found in Porsche's and Vipers are already strong to begin with. If it's shift time you're after, learn to shift faster!

777vegasviper 07-30-2009 09:11 AM


Originally Posted by mousecatcher (Post 2480716)
sure, when stopped and engaging any gear you need to use the clutch of course, and again this has nothing to do with the sequential mechanism.

Quote:
Originally Posted by mobonic http://images.ibsrv.net/ibsrv/res/sr...s/viewpost.gif
Aw... so you still have to use the clutch, but inly for downshifting.

"nope. again, due to dog rings, you do not have to use the clutch period. nothing to do with the sequential mechanism."



both of the above are your quotes, which one is correct?

mousecatcher 07-30-2009 12:47 PM


Originally Posted by 777vegasviper (Post 2481320)
both of the above are your quotes, which one is correct?

"you do not have to use the clutch period" is incorrect. When stopped, you have to use the clutch. I should have said that you do not have to use the clutch when downshifting either.

analogmike 07-31-2009 05:55 PM

I have the hollinger-sourced sequential as the stock tranny in my '08 GT3 cup. You should use the clutch when downshifting, and you need to accurately blip the throttle to match revs.

Upshifts ARE fast but not so easy, in the higher gears it's easy to crunch the box if you don't hit it just right. It's cost me about $1K per hour to service my gearbox this year :(. And that's not unusual.

Here's what is looks like from inside the car:

http://www.analogman.com/911/gt3cup/shifter.jpg

http://www.youtube.com/watch?v=j24yAwGrsRo

ScottKelly911 08-01-2009 02:26 AM


Originally Posted by jpvarghese (Post 2480865)
I don't see the point to those expensive gearboxes when manual gearboxes found in Porsche's and Vipers are already strong to begin with. If it's shift time you're after, learn to shift faster!

it has nothing to do with the strength of the transmission, it has to do with the speed of the gear changes and more importantly preventing missed shifts. Also, no matter how fast someone shifts in a conventional transmission it's still no match for a sequential. Think differently...watch the video posted below by analogmike. Also, you don't have to worry about binding synchros and you're always staying at the right place in the powerband or on Turbo cars, staying on boost. None of that really matters for street use or even at the lower levels of racing, but in the world where fractions of a second per lap makes a difference over an entire race, it's HUGE. Imagine two cars, same driver, same cars, only difference is transmissions. For example let's say to shift a normal car takes 1/2 second to shift vs 1/4 second to shift with a sequential transmission. You're on a track that takes 60 shifts total (both up and down shifting) per lap. The sequential is going to save you 15 seconds in shifting alone, now multiply it by thirty laps for the entire race and the benefits become pretty obvious. That's assuming that the conventional transmissioned car had a perfect run and didn't miss any gears. I hope that explains the benefits a little better.


Originally Posted by analogmike (Post 2483580)
I have the hollinger-sourced sequential as the stock tranny in my '08 GT3 cup. You should use the clutch when downshifting, and you need to accurately blip the throttle to match revs.

Upshifts ARE fast but not so easy, in the higher gears it's easy to crunch the box if you don't hit it just right. It's cost me about $1K per hour to service my gearbox this year :(. And that's not unusual.

Here's what is looks like from inside the car:

http://www.analogman.com/911/gt3cup/shifter.jpg

http://www.youtube.com/watch?v=j24yAwGrsRo

Oh how I LOVE the sound of Straight-Cut gears!!!


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