Crazy Fast GT Racer

shaeff

Kurt is FTMFW x2!!!!
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Mar 30, 2005
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I've watched that video so many times! Every time, I love it more!
 

figgie

Supramania Contributor
Mar 30, 2005
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is that a GT2 Cup car?

anyway. There are numerous way to implement the flat shifting.

With DBW, you can do a throttle closure of X percent based on moving up a gear or throttle blipping based on moving down a gear. As IJ. stated it is based on a strain gauge and of course have a nice high end ECU (MoTeC, Pectel, Magnetti Marelli, OBR, Bosch, EFI Technologies, etc). Flat shifting is the "old" way of doing it by cutting the ignition system while keeping the throttle at 100%. With DBW. The Throttle can be closed enough to match speed with where the next gear needs to be and then open to 100% in a gradual but super quick slope. It keeps the seq gear changes as smooth as ANY luxury sedan.

grimreaper;1149624 said:
the new ss cobalt has some sort of no lift shift setup, ecu holds the rpms for you while you shift...


That is NOT a "shift without lift setup". The idea behind shift without lift is to match the lower RPMs of the higher gear by cutting enough power to slip the tranny into gear if you were to not have syncros per say.
 

grimreaper

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That is NOT a "shift without lift setup". The idea behind shift without lift is to match the lower RPMs of the higher gear by cutting enough power to slip the tranny into gear if you were to not have syncros per say.

i see, i wonder if its just a GM given label then for the ss...thanks for clearing that up
 

2JZ_MA70

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Aug 28, 2007
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They guy has a DSG (semiautomatic manual transmision... ) or direct shift transmision. They have been around for years ( WRC, GT, F1... ) and it is much diferent than normal manual transmision. BMW and VW are few of the manufacturers that have those in production cars now days.... It takes 20 ms to shift gears. But it is hydrolicly operated transmission.

There are variations that would get somewhat the same response. Dawg box is when teh sincronisers are eliminated and special addapters are welded to the gear cone to alow faster shifts and also takes more abuse. I might be able to snap a picture of one of those...

i have a pdf file that explains the operation but it is too big to upload.
 
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figgie

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2JZ_MA70;1151326 said:
They guy has a DSG (semiautomatic manual transmision... ) or direct shift transmision. They have been around for years ( WRC, GT, F1... ) and it is much diferent than normal manual transmision. BMW and VW are few of the manufacturers that have those in production cars now days.... It takes 20 ms to shift gears. But it is hydrolicly operated transmission.

There are variations that would get somewhat the same response. Dawg box is when teh sincronisers are eliminated and special addapters are welded to the gear cone to alow faster shifts and also takes more abuse. I might be able to snap a picture of one of those...

i have a pdf file that explains the operation but it is too big to upload.


No they are not hydraulic operated :)

Basically It is either a

Quaife
Xtrac

Those are TRUE sequential transmissions with straight cut gears. Porsche Cup cars use Quaife btw ;)

http://www.porsche.com/usa/eventsandracing/motorsport/racingcars/911gt3cup-s/technologyandconcept/