Opinions on downshifting

370guy

^^ 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)

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bkleeman

Engines are for going, not for stopping. How fast you can stop is determined by the tires and the available traction. You can easily reach the threshold of the tires using just brakes so the engine won't help you stop any faster. All you are doing is adding stress and wear to the driveline. Brake pads are cheap and that's what they're for and they'll stop you faster than any engine will.

I hit every gear on the downshifts, but it's a matter of preference. If you're going to skip gears on the downshift, then keep in mind that your rev-match will need to be a higher blip than if you hit every gear (the rev difference going from 5th to 2nd is more than 5th to 4th or 4th to 3rd or 3rd to 2nd) - so it's either a bunch of small blips or one big one.

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.

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Brian Kleeman
Nissan 370Z - Pirelli World Challenge GTS #07
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cossie1600

too much fast and furious...

SPOHN

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.

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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.

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.

wstar

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).

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cossie1600

Just buy an automatic

SPOHN

If your lazy and want less reliability. Also add SRS on rop of that also.

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wstar

Guilty as charged!
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.

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cossie1600

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

SPOHN

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

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mantella87

Apples to oranges.

cossie1600

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

SPOHN

I don't personally double clutch ever. I was just pointing it out.

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