Opinions on downshifting

SPOHN · 03-05-2012, 01:57 PM

Quote:

Originally Posted by bkleeman

I'd also recommend leaving the car in gear until you're ready to do your one big blip. If you're clutching to neutral, then you're blipping the engine from idle which will require an even bigger blip - much more opportunity for a mis-match and chirping the rear tires which can lead to a spin.

This was defiantly what I was doing. I wouldn't clutch to neutral ever. And I have down pretty good. All and all I wanted to be assured it was OK.

mantella87 · 03-07-2012, 04:14 AM

Quote:

Originally Posted by ryan0

seriously?

Double clutch - Wikipedia, the free encyclopedia

I hope you knew what double clutching was before you read that Wikipedia article. I'm not saying you have to double clutch with a synchronized transmission, but I promise you that you will reduce synchro-wear if you do.

ryan0 · 03-07-2012, 11:08 AM

Quote:

Originally Posted by mantella87

I hope you knew what double clutching was before you read that Wikipedia article. I'm not saying you have to double clutch with a synchronized transmission, but I promise you that you will reduce synchro-wear if you do.

wikipedia just taught me how to drive a stick.

but i bet you will also reduce synchro-wear if you just only use 2nd and 5th gear.

mantella87 · 03-07-2012, 07:07 PM

Quote:

Originally Posted by ryan0

wikipedia just taught me how to drive a stick.

but i bet you will also reduce synchro-wear if you just only use 2nd and 5th gear.

Apples to oranges.

cossie1600 · 03-05-2012, 12:55 PM

Quote:

Originally Posted by mantella87

Double clutch and avoid engine breaking.

too much fast and furious...

wstar · 03-05-2012, 04:49 AM

My vote would be that you should be engine braking anytime you're foot-braking. If you want to skip a gear to save some work and attention-span that seems fine, but I'd still leave the higher gear engaged until you're ready to make the jump IMHO. I don't really see how holding in the clutch and braking in neutral is helpful to any aspect of the process.

370guy · 03-05-2012, 12:01 PM

^^ doesnt get it...

You only NEED t o double clutch if your transmission does not have synchros. Double clutching doesnt help on a syncronized transmission (which all modern cars have)

wstar · 03-07-2012, 11:56 AM

Obligatory: Vin Diesel Rips Paul Walker (The Fast And The Furious) - YouTube

In any case, it is factually true that even on a modern transmission, using a double-clutch technique (in addition to normal rev-matching) will make the engagement smoother. When combined with heel-toe on a downshift, the extra release-push cycle on the clutch pedal mid-shift (while the stick is transitioning through N) basically serves to "rev match" the front side of the transmission to the engine revs you're blipping up to for the next gear. I only ever tried this playing around on the street a bit, I have no idea if it's practical.

Either way, the whole double-clutching issue is orthogonal to the basic questions about skipping gears on downshift (although as you skip more gearing, double-clutch might become more worth it).

cossie1600 · 03-07-2012, 03:03 PM

Just buy an automatic

SPOHN · 03-07-2012, 04:25 PM

Quote:

Originally Posted by cossie1600

Just buy an automatic

If your lazy and want less reliability.

Also add SRS on rop of that also.

wstar · 03-07-2012, 04:34 PM

Quote:

Originally Posted by SPOHN

If your lazy

Guilty as charged!

Quote:

and want less reliability.

We'll see. In the long run I expect the 7AT to need a rebuild before the 6MT does for sure. In the short term though, I've flogged the crap out of mine for 3 years now without issue, with the only upgrade being a very small extra cooler for the fluid. Whereas with the 6MT guys, we've already seen issues with clutch slave cylinders and some aftermarket flywheel failure stuff.

cossie1600 · 03-07-2012, 04:40 PM

Quote:

Originally Posted by SPOHN

If your lazy and want less reliability.

Also add SRS on rop of that also.

It would be faster than double clutching down each gear at all the corners. I thank vin diesel for the tip

SPOHN · 03-07-2012, 05:47 PM

Quote:

Originally Posted by cossie1600

It would be faster than double clutching down each gear at all the corners. I thank vin diesel for the tip

It would be faster. But being all this would happen during the braking transitions it wouldn't matter.

cossie1600 · 03-07-2012, 08:14 PM

Quote:

Originally Posted by SPOHN

It would be faster. But being all this would happen during the braking transitions it wouldn't matter.

You must have either a really long braking distance or really quick left foot to double clutch the car down to the gear you want

cossie1600 · 03-07-2012, 09:12 PM

Only Vin Diesel, F&F fanboys and truckers do

03-05-2012, 04:49 AM	#6 (permalink)
wstar A True Z Fanatic Join Date: Mar 2009 Location: Houston, TX Posts: 4,024 Drives: too slow Rep Power: 3595	My vote would be that you should be engine braking anytime you're foot-braking. If you want to skip a gear to save some work and attention-span that seems fine, but I'd still leave the higher gear engaged until you're ready to make the jump IMHO. I don't really see how holding in the clutch and braking in neutral is helpful to any aspect of the process. __________________ 7AT Track Car! Journal thread / Car setup details

03-05-2012, 12:01 PM	#7 (permalink)
370guy Enthusiast Member Join Date: Sep 2011 Location: knoxvile, TN Posts: 298 Drives: 370+Viper+Vette=Fast Rep Power: 15	^^ doesnt get it... You only NEED t o double clutch if your transmission does not have synchros. Double clutching doesnt help on a syncronized transmission (which all modern cars have) __________________ - TopSpeed - Z1 - AMS - K&N - Password:JDM - Nismo - Evo-R - Megan Racing -

03-07-2012, 11:56 AM	#8 (permalink)
wstar A True Z Fanatic Join Date: Mar 2009 Location: Houston, TX Posts: 4,024 Drives: too slow Rep Power: 3595	Obligatory: Vin Diesel Rips Paul Walker (The Fast And The Furious) - YouTube In any case, it is factually true that even on a modern transmission, using a double-clutch technique (in addition to normal rev-matching) will make the engagement smoother. When combined with heel-toe on a downshift, the extra release-push cycle on the clutch pedal mid-shift (while the stick is transitioning through N) basically serves to "rev match" the front side of the transmission to the engine revs you're blipping up to for the next gear. I only ever tried this playing around on the street a bit, I have no idea if it's practical. Either way, the whole double-clutching issue is orthogonal to the basic questions about skipping gears on downshift (although as you skip more gearing, double-clutch might become more worth it). __________________ 7AT Track Car! Journal thread / Car setup details

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03-07-2012, 03:03 PM	#9 (permalink)
cossie1600 A True Z Fanatic Join Date: Jun 2009 Location: californee way Posts: 5,380 Drives: 370, Leaf Rep Power: 31	Just buy an automatic

03-07-2012, 09:12 PM	#15 (permalink)
cossie1600 A True Z Fanatic Join Date: Jun 2009 Location: californee way Posts: 5,380 Drives: 370, Leaf Rep Power: 31	Only Vin Diesel, F&F fanboys and truckers do