lets talk double clutching.

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Re: lets talk double clutching.

Postby Yoshi » Mon Apr 11, 2011 5:54 pm

you're at the end of my knowledge base. I can't answer your question good sir.
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Re: lets talk double clutching.

Postby ten2doyle102 » Mon Apr 11, 2011 6:12 pm

Ah... I was just wondering cause I know of a couple guys locally that have subies with 1st and 2nd dog cut for more strength.
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Re: lets talk double clutching.

Postby M20_fever » Mon Apr 11, 2011 6:37 pm

You can have a synchronized transmission with straight cut gears, I know of people who older muscle cars with them and they don't double clutch all the time. Dog gears are different though, "dog boxs" use straight cut gears, but the name comes from how the gears mate with the shafts. Dog boxes do not habe syncros, so you have to double clutch to shift.
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Re: lets talk double clutching.

Postby ten2doyle102 » Mon Apr 11, 2011 6:49 pm

Well, maybe they are just straight cut. I always thought a straight cut gear was a dog gear. ;) Learned something new today....can I go home?
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Re: lets talk double clutching.

Postby M20_fever » Mon Apr 11, 2011 7:29 pm

Nope, two different things. I would assume any car that will see street driving would not have a dog box, but rather just straight cut gears.
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Re: lets talk double clutching.

Postby ponycarman » Fri Apr 15, 2011 8:19 pm

To answer your question about why the clutch out in neutral in necessary. Im not completly sure about this but I was just thinking about it today and this is what I came up with. At least from just thinking about the mechanics of a manual transmission. I think its because when you rev match it doesnt just have to deal with matching the rpms of the engine. You are also matching the speeds of the two gears that are going to mesh. And if keep the clutch disconnected then they are freewheeling or just spinning from the speed of the car. But if you let the pedal out in neutral engaging the clutch and rev match then it would directly be connected to the gearing in the transmission and you would be adjusting the speeds of the gears inside the tranny to match that of the gear you want to enter. Im not completely sure on this but this is my best guess. I remember alot from school when I had to rebuild a couple transmissions and if Im remebering right on how they work then this would be the reasoning. Just my thoughts. Let me know if I need to explain further.
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Re: lets talk double clutching.

Postby M20_fever » Fri Apr 15, 2011 8:47 pm

actually that makes perfect sense.
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Re: lets talk double clutching.

Postby ponycarman » Fri Apr 15, 2011 9:09 pm

Really? Cool! Haha alot of times I just stay quiet to keep from making a fool of myself or sounding stupid hehe.
Last edited by ponycarman on Sat Apr 16, 2011 6:31 pm, edited 1 time in total.
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Re: lets talk double clutching.

Postby M20_fever » Sat Apr 16, 2011 2:54 am

we all sound stupid sometimes, thats how we learn. ;)
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Re: lets talk double clutching.

Postby 87e30 » Sat Apr 16, 2011 3:31 pm

Yeah, I'm sure I've said some things that made ppl ask WTF I was thinking. lol
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Re: lets talk double clutching.

Postby ten2doyle102 » Sat Apr 16, 2011 6:51 pm

It seems cool.... It would really just take alot of practice I think. To me though, it still seems faster to rev match than doing that...
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Re: lets talk double clutching.

Postby ponycarman » Sat Apr 16, 2011 10:44 pm

Yeah its kinda neat and makes sense. Check out the nissan 370z. The car that replaced the 350z. They did a review of it on top gear and Jeremy Clarkson demostrated a neat feature on the car. It has some type of system that automatically rev matches the engine for the gear you are going to change into. It was pretty neat. Check it out.
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Re: lets talk double clutching.

Postby 87e30 » Sat Apr 16, 2011 11:53 pm

How does it know what gear YOU want to go into? What if you were planning on skipping a gear? (Very common to do on a motorcycle, not as often in a car, but it does happen) How does it know if you're planning to upshift or downshift? Maybe I should just look it up for myself. lol
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Re: lets talk double clutching.

Postby M20_fever » Sun Apr 17, 2011 2:32 am

because its a paddle shifter, so when you flip the downshift paddle it blips the throttle to rev match.
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Re: lets talk double clutching.

Postby ponycarman » Sun Apr 17, 2011 3:48 am

The 370z has a regular stick shift. Heres the vid on youtube the part with the 370z and the demostration of their system is at about 5:45 into the video.

http://www.youtube.com/watch?v=9J8aPPvEcJM
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