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downshifting into second -> shudder?

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Old 09-28-2004, 01:06 PM
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downshifting into second -> shudder?

I only have 481 miles on the car, but I did notice this on the loaner they gave me to test drive and on this car. I hope this is norma:

If im at say 4000 rmp in third or fourth gear (may happen in 5th - havn't tried it yet) and I downshift to second, not lighting fast, but quick - I get this shudder right before it goes into 2nd. Feels like the tranny is shaking on its mounts. NO metal sound or noise just a shudder. Can someone explain for me.

I havn't been abusing the car at all, so I don't think this is my doing.

greg
Old 09-28-2004, 01:10 PM
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4000 in 4th downshifting to 2nd will put you at approximately 6k rpms in second.. are you rev matching?
Old 09-28-2004, 01:16 PM
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Well, maybe im wrong about the RPM on the new car - As I recall I was in 4th, let off the gas costed a bit (so I lost 1000 rpm maybe) then sliped it into 2nd - then shudder. It happened in third the same way, so I wasn't going fast at all, should have been 500 rpm (guessing) drop once it went into 2nd.

I didn't rev match. I do somtimes but not all. Mostly when I really on an engine I'll do that, but if Im lazy around town then not all the time. I don't force the gear either, just a slight flick of the wrist. I noticed that if I let the car slow down real slow before downshifting it wont shudder. And it never shudders upshifting.
Old 09-28-2004, 01:19 PM
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When downshifting, especially 2 gears, you need to rev match... You can get away with a 1 gear upshift if you allow enough time for the syncros to catch up.. you should hear a spooling up kind of noise.. It's not good for your synchros..

try rev matching :D
Old 09-28-2004, 01:24 PM
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triple cone synchros in 1st 2nd and 3rd. probably feeling the syncros doing their job.
Old 09-28-2004, 03:16 PM
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Not too good for the clutch either.

Match revs, that's why God gave you a heel! :D
Old 09-29-2004, 03:29 AM
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Rev matching would only be useful if you're downshifting to accelerate, rather than decelerate. In your case it seems that you're downshifting slowing down, maybe to go round a corner. I also find that the car is very jerky in 2nd at very low rev. You need to play with the clutch and gas to stop the jerking. I also find that the clutch on the 8 is not as forgiving as on other Japanese cars. The sweet spot on the clutch seems very small and needs precise clutch release. It has taken me more time to get used to the 8's clutch sweet spot than any other car I have driven.
Old 09-29-2004, 03:37 AM
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You definitely need to learn to revmatch, and it sounds like you're downshifting into 2nd where it would be at a high RPM, meaning that the synchros are definitely working hard to match engine and tranny speeds. It also sounds to me like you're popping the clutch. Learn to rev-match, and use the clutch with finnesse and you shouldn't have a prob.
Old 09-29-2004, 08:50 AM
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I don't think it has anything to do with "poping the clutch". The shudder happens when the clutch is depressed and the I move from 3rd to 2nd. As I shift down, right before the shifter "snicks" into gear is when I get the shudder. I never "pop" the clutch, rather I ease it out to get a smooth transition.

I did try double clutching, and this seems to work, but I will need to try it more to confirm.

greg
Old 09-29-2004, 08:54 AM
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I always double clutch.. I can't do it any other way .. but you don't NEED to.. you just need to match the rpm's.. you should be able to do this with the clutch engaged.

What part of Louisiana are you from? I was born and raised in the New Orleans area.

Originally Posted by silver1.3
I don't think it has anything to do with "poping the clutch". The shudder happens when the clutch is depressed and the I move from 3rd to 2nd. As I shift down, right before the shifter "snicks" into gear is when I get the shudder. I never "pop" the clutch, rather I ease it out to get a smooth transition.

I did try double clutching, and this seems to work, but I will need to try it more to confirm.

greg

Last edited by guy321; 09-29-2004 at 08:59 AM.
Old 09-29-2004, 09:04 AM
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Originally Posted by guy321
What part of Louisiana are you from? I was born and raised in the New Orleans area.
Lafayette, Its cool b/c its a realitively small town and there arn't many 8's - I get a ton of looks. The other day me and my wife went to Sams, I was walking away from my car and an elderly fellow, his wife and what looked like his grandaughter (15 year old or so) stoped me and he asked if they could check out my car, they all - and I quote - "fell in love with it when they saw it". That was cool, never had anybody say THAT about a car I've owned. :D
Old 09-29-2004, 09:09 AM
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Why would you need to downshift to slow down? That's what brakes are for :p

I typically downshift so that I can maintain my powerband..

Originally Posted by hotpot
Rev matching would only be useful if you're downshifting to accelerate, rather than decelerate. In your case it seems that you're downshifting slowing down, maybe to go round a corner. I also find that the car is very jerky in 2nd at very low rev. You need to play with the clutch and gas to stop the jerking. I also find that the clutch on the 8 is not as forgiving as on other Japanese cars. The sweet spot on the clutch seems very small and needs precise clutch release. It has taken me more time to get used to the 8's clutch sweet spot than any other car I have driven.
Old 09-29-2004, 09:10 AM
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Nice, Good food out there, I miss it!!

A buddy of mine is from Delcambre parish out that way.

Originally Posted by silver1.3
Lafayette, Its cool b/c its a realitively small town and there arn't many 8's - I get a ton of looks. The other day me and my wife went to Sams, I was walking away from my car and an elderly fellow, his wife and what looked like his grandaughter (15 year old or so) stoped me and he asked if they could check out my car, they all - and I quote - "fell in love with it when they saw it". That was cool, never had anybody say THAT about a car I've owned. :D
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