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throttle upshifting?

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Old Jan 29, 2010 | 12:34 PM
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From: Anacrime
throttle upshifting?

I've always wanted to learn that so, from my understanding its basically waiting for the right moment when your rpm and speed matches and then... I'm lost from there
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Old Jan 30, 2010 | 07:47 AM
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You take it out of gear while letting out the throttle enough to drop the RPMs to the point where they match the road speed of the car in your next gear. Then you should be able to shift into the next gear.

Normally when you shift, there will be a slight missmatch between the engine and tranny speed. Which is why you have a clutch and synchos.

Clutchless upshifting is normally done on a tranny that is built to take the abuse. Your stock tranny is not and if you shift it this way you will break things, starting with your synchros.

Work on shifting smoothly (rev match) with the clutch. It will pay off better in the long term.
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Old Feb 1, 2010 | 03:53 PM
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From: Anacrime
^^ thanks
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Old Feb 14, 2013 | 09:10 PM
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How long is a race tranny built to last through clutchless shifting? I bought a racing trannt built at Pineapple (I still have to ask them if it was built to withstand this) but I am interested because in some occasions a quicker shift could be useful.
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Old Feb 14, 2013 | 09:46 PM
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Unless it is a dogring engagement gear set you should use the clutch. With a dogring box you basically remove the load from the trans with a slight lift of the throttle and shift as fast as you can. The faster the better.

A full synchro box can be shifted without the clutch, but not quickly, and it is a tough thing to do smoothly. On a street trans I can go up and down the gears without a clutch after driving the car for a while. You have to know the exact amount of RPM change between gears and the have to be patient. Once the RPM's drop or you blip the throttle on a downshift you click it into gear.

Speed shifting a synchro box is asking for trouble no matter who makes it. Mazda happens to be even less forgiving than most if you screw up.
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Old Mar 6, 2013 | 06:57 PM
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if you have a commute in the morning that has traffic for any decent length of time, it is a great place to practice clutch-less up and downshifting. speed is slow enough to get a feel for it. I learned this way when my slave blew one time >_< I personally rev match my street transmission almost religiously now. I don't even realize I am doing it unless I'm going all out on the track dropping three gears into a tight corner from 80mph, granted that brings in heel and toe unrelated to OP.
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