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clutching in increases rpm's?

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Old Jul 18, 2009 | 03:34 AM
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Default clutching in increases rpm's?

ok so my car is a 08, got it brand new, has less than 2k on it.

i noticed it in the test drive that when i engage the clutch, the rpm's increase about 2-3 hundred. i know what youre thinking " youre still on the gas and are clutching in too early" but ill get off the throttle for like 1 or 2 seconds and clutch in and it will still happen. all my friends that drove it said the same thing without me even mentioning it

is normal?
Old Jul 18, 2009 | 01:06 PM
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So wait ...

You are driving along in second, you take your foot off the gas, disengage the clutch and change to third, but in the process the car jumps 200RPM?

If you are waiting a moment to shift I don't see how or why this would happen. If not I would it is just a bit of throttle hang during shifting.
Old Jul 18, 2009 | 01:22 PM
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yeah like picture this...driving in 1st, get off gas noticeably early, clutch in, rpm's increase about 200, does it in every gear. does it even more if i go to shift normal instead of getting off gas extra early (which is still before i clutch in)

a couple of my buddies said its probably normal to help with smoother shifts...
Old Jul 18, 2009 | 01:27 PM
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Hmm, I will let you know what my 08 does, I have never noticed it, but I never release the throttle completely when shifting to avoid jerking or losing RPMs.

The only time I am completely off the throttle is when heel-toeing ... but I don't think I have noticed it there either.

I will let you know what I find.
Old Jul 18, 2009 | 01:40 PM
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min did it it'll stop its cuz i would push that clutch down really fast probly before all the gas could get out of the line its mormal just shift slower it stopped happin now and my car has about 17k on it its nomal
Old Jul 18, 2009 | 01:50 PM
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The engine is holding up the rpm between gears so you get a smoother shift instead of the clunk jerk forward as you let the clutch out then hit the gas. Nothing to worry about. Having the A/C on will also affect the engine idle between gears. In my xB it actually shifts worse with the A/C on. Don't forget you really do not control the throttle valve directly - you are "drive by wire" and the ECU actually controls the throttle. You only think you control the throttle . . . muooo haa ha ha.
Old Jul 18, 2009 | 02:40 PM
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yeah electronic throttle flt lol
Old Jul 18, 2009 | 02:48 PM
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yea dude mine does that too, its weird. stupid drive by wire.
Old Jul 18, 2009 | 04:46 PM
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My g/f's new xD does it too. I thought she was not releasing the gas when she pushed the clutch in but it did the same when I drove it.

We're probably going to do a lightweight pulley for her at some point. That should resolve some of it, since the crank will have less rotating mass and less inertia.
Old Jul 18, 2009 | 06:25 PM
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yeah i was thinkin either a lightweigh pulley or even a flywheel down the road would fix it and make the rpm's drop quicker
Old Jul 18, 2009 | 08:31 PM
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its for smothe driving also has to do with drive by wire delay...but yea a light flywheel will fix it but also make ur car a not very comfortable daily driver.. its like tryna shift with ac on below 3k
Old Jul 20, 2009 | 05:14 AM
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its completly normal. my 08 does the same... dont be scared of clutch squeak either if it happens to u... just the fork. it is for smoother shifting. its called like a revmatch or sumthing. i know the 370z has it and its just for smoother shifting. but IMO i think its worse. it takes some gettin use to.
Old Jul 20, 2009 | 05:36 AM
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hmmm...this is strange...i didn't think that scions have this..i already blip the throttle while upshifting, i don't think i would be doing this if the car was already doing it for me since the tc is my first manual transmission car...i know the SVT ford focus had it when i read reviews in car and driver...

oh, and cburglb34, light weight flywheels are alittle annoying at first, but you get used to them and before long completely forget you even have one.
Old Jul 20, 2009 | 07:01 AM
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Originally Posted by cburglb34
its for smothe driving also has to do with drive by wire delay...but yea a light flywheel will fix it but also make ur car a not very comfortable daily driver.. its like tryna shift with ac on below 3k
i have a 9lb flywheel and it still does it....so rule out the lightweight flywheel thing
Old Jul 20, 2009 | 07:23 AM
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that sounds like that new synchro-rev match transmission in the new 370z. Try some heel toe action and see if it will rev match for you!
Old Jul 20, 2009 | 12:59 PM
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X2!!!!^^^^ thats what i meant
Old Jul 20, 2009 | 05:07 PM
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well, driving around today, i tried to see if my tc did this, and it doesn't, if i delay while upshifting, the rpms just drop like a rock.
Old Jul 20, 2009 | 07:12 PM
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Originally Posted by draxcaliber
well, driving around today, i tried to see if my tc did this, and it doesn't, if i delay while upshifting, the rpms just drop like a rock.

yes i know, he prob like me hits the clutch fast and hard right after letting off gas and it blips up like 200-300 for a split second then goes DOWN fast! haha then mine bounces to 500 and then back up to 1200 till i shift
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