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Discussion Starter · #1 ·
I have the method down, but it just seems like it would be hard on the engine. (I used to drive a stick-shift farm truck, so I hadn't rev-matched before this car. :D )

For example, when I drop below 2k rpm's in 3rd I double-clutch down into 2nd, first revving it up to about 3k rpm's for a jump of 1k rpm's. It just seems like that is putting a strain on the engine. It makes a revving sound (not an unusual sound for an engine jumping 1k rpm's, but it makes a revving sound) and I'm wondering if this is correct why don't I hear people in traffic revving their engines all over town? (We'll forget for a minute that most people in this country drive slushboxes. ;) ) I don't know, it just seems odd...

So please tell me if it is odd or just fun!! :D (I am especially leery of dbl-clutching while driving beside cops! :eek: )

-snowcat
 

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You don't have to "double clutch" just to rev match and blipping your engine by 1K rpm is by no means tough on the engine. When you have your clutch in during normal rev matching (not double clutching) there is no load on the engine, no harm done. Double clutching is good in that it helps preserve your synchros, but bad in that it's an extra bit of wear on your clutch. You can get nearly the same effect just rev matching, plus rev matching is faster and easier to remember when you're really cookin along. The only time I feel it's necessary to double clutch is going into first gear when I'm slowing down to turn into driveways. Otherwise I just rev match. I don't even have to look at my tach to match anymore, I can pretty much do it by sound. Gotta love the Prodrive muffler!
 

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Discussion Starter · #3 ·
Thanks for the input! I double-clutch without having to think about it - plus, I've heard mixed reports on what's easiest on the parts... But, it's good to know that revving in that amount isn't bad for the engine. :)

-snowcat
 

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1rst gear

when slowing down, my rex just doesnt want to go to 1rst until i am nearly at a dead stop, this bugs me for making quick left turns into traffic, is this normal?
 

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It seems to be. You posted in the right thread. The remedy is rev-match and/or double-clutch.
 

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Example: Car in 3rd gear, shifting to 4th

1. Depress clutch pedal.
2. Pull shifter out of 3rd gear and put in NEUTRAL.
3. Release clutch pedal.
4. Depress clutch pedal.
5. Pull shifter out of neutral and place into 4th gear.
6. Release clutch pdeal.

If you were rev-matching you'd do it right after step 4, before step 5...
 

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I've never quite understood why you'd double-clutch an upshift, but if you don't rev-match a downshift double-clutch, don't waste your time - you're not doing anything.
 

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Discussion Starter · #9 ·
GV27 said:
I've never quite understood why you'd double-clutch an upshift, but if you don't rev-match a downshift double-clutch, don't waste your time - you're not doing anything.
I never double-clutch upshifts, but I always rev-match before re-clutching when double-clutching downshifts.

-snowcat
 

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Slightly above whatever you'll end up in after the shift - you want them matched up, but the rev's will fall slightly as you complete the shift. So in your case, somewhere around 5000 I guess. I do it all by instinct, so I'm not exactly sure off hand.
 

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It also depends on whether you happen to be braking(foot brake) at the same time and how much pressure you are applying when determining what rpm you should land in to match road speed and engine speed.
 

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in the double clutching steps above you forgot to blip the gas pedal, while in netrual with the clutch engaged, and then depress the clutch and shift into the lower gear.

Rev matching is good for eliminating the shock loading on the drivetrain however it does nothing to save the synchros.
From experience, the synchros will wear out sooner than the clutch.
Caveats, if you slip the clutch during hard launches then the clutch will go relatively soon. Normal driving and slipping puts almost no wear on the clutch. Another caveat, synchros will last a very long time, however after a few years and a decent number of 10's of thousands of miles on them, they will start to wear and gradually increase their shifting effort. It creeps up slowly and so it is normaly not noticed till you drive a new tranny. Nothing bad, simply some wear and tear.

Done properly double clutching allows the input shaft to spin up to the next gear's rpm while the tranny is in neutral and the clutch is engaged, almost no clutch wear to speak of.

Try rev matching and notice the effort to shift down into the next gear. Then try double cluthing (includes rev matching while in neutral) and then notice how butter smoth the next gear goes in. That's because you taken a tremendous burden off the synchros.
 

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When I downshift/rev match, I usually get the revs matched well enough so the car doesn't jolt or to where its to low and hurts the clutch. But sometimes I slightly over rev by 200 or so and after a depress of the clutch, I can actually hear the car bouncing off the gears in the transmission. That bugs me alot. Since I had Prelude, I always downshift alot. It's done wonders, and people aways complement how well my breaks are. But since the WRX the boucing bugs me, I hope nothing is going, "KAH KAH" in there.
 

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over revving by 200 or so RMP is great. I believe you may be letting up on the clutch to quickly. The center diff and all wheel drive may be causing the "slop" you are feeling. Try letting up on the clutch pedal a bit slower, especially at the top of its travel where it really grabs. The disk will last indefefinitely with this type of slipping.
 
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