Rallycross Downshifting

[ThatOneEuroE30]

Okay yea that's what I visualizing. And yea rev shifting is what I gave up on. I'll pick it up when I start racing forsure.

[nando]

Got it!
I'll give this tecnique a try,

1. Clutch in
2. Lever to neutral
3. Blip throttle
4. Engage lower gear
5. Release clutch

Thanks everyone,
Ian

don't need to move the lever to neutral. clutch in/blip throttle happens at basically the same time, and you also have your right foot on the brake with the toes on the gas (you can do it without braking too, but typically you do this while entering a corner and scrubbing speed). at this moment you move the lever to the gear you want and release the clutch.

if you time it right it'll slip right into gear at the exact RPM to match the transmission, clutch, and road speed together, and it reduces shock on the clutch/trans/drivetrain.

[ThatOneEuroE30]

Elva yes rev shifting is clutchless shifting. Used most commonly in nascar for faster shifting. I'm a nascar nerd cause I've grown up around it.

[bataangpinoy]

heel toe isn't that tough, it just takes practice. I can't dance for shit either, but I heel toe on every downshift. after a while you don't even think about it.

with the way the pedal is anchored in the e30 though, its more of a toe/side of foot thing lol

[4x4_e30]

Clutchless shifting on a transmission with syncros is bad juju. I do it sometimes just to show off, but I know how to unload the drivetrain properly so it's not too rough. You need a trans with dogleg engagement to do that all the time(NOT dogleg shift pattern).

Revmatching is second nature to me as well. I always get dirty looks from bystanders thinking that I'm revving it up to show off. Sheeple.

[Wh33lhop]

are you revmatching? just forcing it into gear isn't going to work because the synchros and input shaft will have a big difference in speed.

rev matching alone won't help too much since you're clutched in as you're entering the next gear. there is still a tiny bit of friction there but it won't make that much of a difference in input shaft speed. double clutching will but that's a bit harder to learn.

you should be rev matching anyway, but in theory it won't make much of a difference. if he can't find a gear in rallycross my guess is he isn't clutching in all the way due to lack of muscle memory from performance oriented driving (or it could be his synchros just suck). if you can learn to double clutch that will definitely help, but that takes time.

[Wh33lhop]

Clutchless shifting on a transmission with syncros is bad juju. I do it sometimes just to show off, but I know how to unload the drivetrain properly so it's not too rough. You need a trans with dogleg engagement to do that all the time(NOT dogleg shift pattern).

dogleg = shift pattern
dog engagement = big-ass "dog" teeth instead of cone synchros

dogleg engagement is not a thing

jeez I am all kinds of pedantic in this thread. sorry folks.

[henryki]

I remember the first time I drove a standard.... lol.

The worst part is that kids these days won't even know about rev shifting; I figure it won't take too many more years for every stick sporty car to have that automatic rev shifter.

they already have one.....

[ELVA164]

Elva yes rev shifting is clutchless shifting. Used most commonly in nascar for faster shifting. I'm a nascar nerd cause I've grown up around it.

Gotcha. I've done it some in the Cortina but I avoid doing it on downshifts, preferring heel-toe for safety's sake. I'd be curious to know what the gear ratios are on those Nascar boxes, seeing how they're four-speed boxes that allow for a top end of 200+. I would think the RPM drops between shifts would be pretty noticeable, making clutchless shifting pretty brutal on the drivetrain. Do you know if they do this only on oval courses or if they employ in on road courses as well?

dogleg = shift pattern
dog engagement = big-ass "dog" teeth instead of cone synchros

dogleg engagement is not a thing

Troof. The gear parts are called "dogs," and the dog-leg is so named for its shape on the shift pattern. Merely coincidence, but understandably confusing.

Another interesting fact: A dogbox can select any gear at any speed, whereas a synchro box will not allow a downshift from, say, fourth to first. This is because the synchros cannot match the speeds of the input and output shafts and will "prevent" the engagement, where in a dogbox there is no "nanny" keeping the dogs from engaging.

[ThatOneEuroE30]

Gotcha. I've done it some in the Cortina but I avoid doing it on downshifts, preferring heel-toe for safety's sake. I'd be curious to know what the gear ratios are on those Nascar boxes, seeing how they're four-speed boxes that allow for a top end of 200+. I would think the RPM drops between shifts would be pretty noticeable, making clutchless shifting pretty brutal on the drivetrain. Do you know if they do this only on oval courses or if they employ in on road courses as well?

Yup both especially on road courses. They do have a clutch but only use it to go into first. What's funny is from time to time will use the clutch and that's actually on ovals more cause it's easier to gain ground.

[ForcedFirebird]

rev matching alone won't help too much since you're clutched in as you're entering the next gear. there is still a tiny bit of friction there but it won't make that much of a difference in input shaft speed. double clutching will but that's a bit harder to learn.

you should be rev matching anyway, but in theory it won't make much of a difference. if he can't find a gear in rallycross my guess is he isn't clutching in all the way due to lack of muscle memory from performance oriented driving (or it could be his synchros just suck). if you can learn to double clutch that will definitely help, but that takes time.

To me, rev matching isn't about the synchros or getting it into next gear, it's about the smooth transition when the clutch is released as to not upset the car. Some people don't heel toe, but I could never get the hang of it that way. (EDIT: Never mind, you are talking clutch-less shifting)

Shouldn't have to double clutch, if you time things right, there's no clutch needed at all.

[ELVA164]

Shouldn't have to double clutch, if you time things right, there's no clutch needed at all.

True, but since OP hasn't ever done any sort of rev-matching the clutch will allow some "wiggle room" with the blip and will still be a lot more effective than doing nothing at all.

[4x4_e30]

Damn, I got the wording wrong but the concept is the same. Yall knew what I meant haha

[YosemiteSam]

Come on guys. He's clearly granny shifting, not double clutching like he should.

Edit: This guy knows what's up: https://www.youtube.com/watch?v=KmlZZRsckM4

[Smrtpunk]

What i'm doing is taking my right foot off the gas and pushing the clutch down to the floor with my left foot. Then taking my right foot and pushing down the brake pedal. Almost at the same time I'm grabbing the shifter and looking for second gear.

I've driven standard cars for years and I know that this type of shifting does not require any sort of rev matching double clutching or anything like that.

On tarmac everything seems to be great, I can pull this kind of move off without issue numerous times.

My theory is that the engine/trans is moving around too much on the stock rubber mounts as the area's that I'm jumping onto the brakes tend to be quite rutted/rough. I've gone ahead and ordered some condor motor/trans mounts and we'll see how it goes after that.

I should be able to update this thread by the end of the month with how it all goes.

Ian