Am I the only one who double clutches?| Grassroots Motorsports forum |

DaewooOfDeath Dork
6/6/12 10:52 p.m.

I've been watching a lot of race videos from GRM members and it looks like everybody rev-matches but nobody double clutches.

Considering speed is really not that important on a downshift, that double clutching is easier on the transmission and that the whole exercise makes it easier to get the car in the desired gear, what's the downside?

ansonivan Dork
6/6/12 10:59 p.m.

Taking the time to double clutch means you can spend less time braking. This in turn means you must begin braking sooner.

TRoglodyte Dork
6/6/12 11:01 p.m.

Technique.

DaewooOfDeath Dork
6/6/12 11:01 p.m.

In reply to ansonivan:

I'm heel and toe-ing when I double clutch, so I'm on the brakes during all the shifts.

In reply to Troglodyte:

?

emodspitfire Reader
6/6/12 11:03 p.m.

Modern clutches and transmissions are tuff enuf to not require double clutching....

NGTD Dork
6/6/12 11:08 p.m.

I double clutch my street car.

2002 WRX - doing my best to keep the transmission from being a problem.

David S. Wallens Editorial Director
6/6/12 11:10 p.m.

Frank Bullitt double clutches.

DaewooOfDeath Dork
6/6/12 11:12 p.m.

So does Dom Torreto, although he uses it for upshifts.

TRoglodyte Dork
6/6/12 11:16 p.m.

Old truck driving trick to stop the layshaft for straight geared transmissions.

friedgreencorrado PowerDork
6/6/12 11:20 p.m.

In reply to TRoglodyte:

You beat me to it. Might still be something to do in a "minor league" formula or sports racer class (straight cut gears), but in a sedan class, the synchros will do that. And it's a race car, you'll be rebuilding the box anyway..

pimpm3 Reader
6/6/12 11:21 p.m.

I do and I have for as long as I can remember. Now it just feels wrong if I don't. I have to agree if you heel toe while double clutching it should not effect your braking.

EvanB GRM+ Memberand UberDork
6/6/12 11:23 p.m.

Everyone is granny shifting, not double clutching like they should.

Streetwiseguy SuperDork
6/6/12 11:23 p.m.

There is one corner at Gimli where I don't use the clutch at all- heel/toe, rev match, slip it into second, finish the sweeper and back on the power.

Keith GRM+ Memberand MegaDork
6/6/12 11:24 p.m.

I double clutch. I learned on the old Land Rover, and the trans in the Seven is just a bit ornery on the 3-2 shift so I got in the habit of doing it in that car too. And it spread from there. I'll bet that the Targa videos show me doing it on the rally stage.

(checking)

Yup, most of the time.

David S. Wallens Editorial Director
6/6/12 11:31 p.m.

And Roy Scheider was such a bad-ass that he could double-clutch an automatic: http://youtu.be/9vACWV5sRcY

Derick Freese SuperDork
6/6/12 11:31 p.m.

Yeah, I double clutch. I learned the rev match in about 30 minutes when my slave cylinder in my Nissan took a dump and I couldn't buy a new one until pay day. I learned to double clutch my Jeep when I thought my sycros were toast. Now, I double clutch everything.

DaewooOfDeath Dork
6/6/12 11:38 p.m.

David S. Wallens wrote: And Roy Scheider was such a bad-ass that he could double-clutch an automatic: http://youtu.be/9vACWV5sRcY

That video is full of terrifying suspension behavior!

Trans_Maro SuperDork
6/6/12 11:40 p.m.

I double clutch in my daily drivers to save the synchros.

I don't in the racecar because I've got enough crap going on already.

EvanB GRM+ Memberand UberDork
6/7/12 12:14 a.m.

DaewooOfDeath wrote:
David S. Wallens wrote: And Roy Scheider was such a bad-ass that he could double-clutch an automatic: http://youtu.be/9vACWV5sRcY
That video is full of terrifying suspension behavior!

Is that the building in the beginning the same one they come out of in the Gumball Rally?

Appleseed PowerDork
6/7/12 12:47 a.m.

Only when I drive the dump truck.

Max_Archer Reader
6/7/12 1:02 a.m.

I learned at Skip Barber and couldn't stop doing it in my street cars for a few weeks after, but it's not something I do regularly. I can't really do it right in the Mazda2 anyway, the clutch engages way too high for it to feel right.

ransom GRM+ Memberand Dork
6/7/12 1:14 a.m.

The second gear synchros in the 2002 were weak for most of its life so far, so it's a pretty ingrained habit.

I'm trying to remember whether I did it in the E30, and I would bet I did at the track day. And I think I did on that one pesky autocross that needed a 2-1 downshift 50 yards after the start...

I'm kind of amazed that I don't double-clutch the WRX out of habit.

Street and autocross there's less time for it, and not double-clutching would be nice. In the E30, on a full road course, there was enough time on the brakes that the double-clutching would be downright leisurely on the 4-3 and 3-2 downshifts...

JohnyHachi6 Reader
6/7/12 1:22 a.m.

I'll double clutch on downshifts when heel-toe braking, but typically only on a 2-1 (rarely in auto-x) or 3-2 shift. Doing a 2-1 is very tough without the double clutch; most transmissions I've raced do not like going back into 1st at speed even if the syncros are in good shape.

ncjay Reader
6/7/12 1:57 a.m.

In my world, there is no reason to double clutch - ever. Much of the time I don't use the clutch at all. Normal operation is to go from a gear to neutral with no clutch, blip the throttle and go into the lower gear either with or without the clutch.