Emergency braking - dip the clutch?

[fro]

If I completely relied on my brakes at the track and none of the engine I reckon they would last only a lap or two before getting too hot.

Yeah, but what you are talking about there is heavy braking... you are expecting to have to apply the brakes as hard as you can, frequently.

Emergency braking is what you do in a "panic stop", in scenarios described earlier (kid/dog/goat/rock runs out on road, goblins appear from the earth, etc). In this instance, it's a single application, single instance.

If you or anyone has the presence of mind to be gearing down while applying the maximum braking effort available, good luck to them. I (and almost, if not all of the driving public, I would suggest) is not sufficiently skilled to be gearing down in a panic situation.

That ABS knocks so much off Joe Publics stopping distance shows that they don't know how to effectively use all braking capacity available to them, and asking them to gear down while using cadence is probably more than they can stand...

/gross generalisation rant...

[0x2DLVR]

What 02PRUV is trying to say i think, is that he grabs a gear just incase the situation changes iecontinuing to brake will lead to you hitting some thing.

I have experienced this i was driving along a dirt road when a right angle turn appeared, i hit the brakes only i was going to stop in time, so instead og going into the trees and damaging the car i put in second, thurn the wheel and put my foot down.

We are talking about emergancy braking you dont know what is going to happen, is the car going to pull up before that kid that just stepped out on the road or are you going to have to drop back a gear and drive around it.

If we were talking about stopping in the shortest time possible, yes brakes only with the clutch in.

At least someone knows what I'm saying

[bahaimus]

At least someone knows what I'm saying

Yes, but he still got the braking done first.

[0x2DLVR]

Yeah, but what you are talking about there is heavy braking... you are expecting to have to apply the brakes as hard as you can, frequently.

Emergency braking is what you do in a "panic stop", in scenarios described earlier (kid/dog/goat/rock runs out on road, goblins appear from the earth, etc). In this instance, it's a single application, single instance.

If you or anyone has the presence of mind to be gearing down while applying the maximum braking effort available, good luck to them. I (and almost, if not all of the driving public, I would suggest) is not sufficiently skilled to be gearing down in a panic situation.

That ABS knocks so much off Joe Publics stopping distance shows that they don't know how to effectively use all braking capacity available to them, and asking them to gear down while using cadence is probably more than they can stand...


/gross generalisation rant...

And that's what I was saying before about the average person is better to just hit the brake. ABS was invented for Joe Public. For the skilled people out there no ABS is better than standard shitty ABS any day

[0x2DLVR]

Yes, but he still got the braking done first.

You have to start somewhere. The idea is to scrub off maximum amount of speed as possible. Regardless what happens after you initially hit the brakes

[bahaimus]

The greatest % of speed will be washed off in the latter part of the braking.

[tinkerbell]

ie "in the last 5m of braking, you wipe off half your speed"

??? how does that ford vs ford anti-speeding ad say?

[The Pupat]

And that's what I was saying before about the average person is better to just hit the brake. ABS was invented for Joe Public. For the skilled people out there no ABS is better than standard shitty ABS any day

I'll take ABS any day of the week. It makes stopping fast insanely easy. I can do it my non-ABS car but then I jumped in another car and hit the same course faster in an ABS car and it was over before I knew it no fuss, no nothing just stops. Absolutely awesome.

[Jim]

I can out brake the ABS in the Statesman, but it's ABS was junk compared to good euro stuff. The stateman's was like having disc rotors that looked like an old LP record left in the sun, it would push back against your foot so violently you risked getting kneecapped by the steeringwheel, compared to my mate's 528i which was a very gentle dubbadubbadubba at the brake pedal you could only just feel, and no little incremetal lockups like the holden system.

Having said that, where ABS truly comes into it's own is when you have a situation where you have 100% survival instinct input and 0% rational thought input, such as your usual "Oh Shit!" incidents.

The best thing you can do with ABS is make sure it works, then forget you have it.

[fro]

The best thing you can do with ABS is make sure it works, then forget you have it.

And remember that you don't have it, when you're in a car that doesn't have ABS!

ABS is one of those things (like airbags) that you hope you never have to use. And with good attentive driving, that might be true...

[Jim]

Yep. Best way to survive an accident is to not have one.

[The Pupat]

I've only used the euro bosch stuff in pugs so wouldn't have a clue on the other systems. That said based on those systems I reckon it is the greatest safety feature made short of the seatbelt.

[rowdytoot]

in the last 5m of braking, you wipe off half your speed

kewl so if I'm doing 100 km/hr 5 metres out, I'll only be doing 50 when I hit.. wow!..sweet... I'll have to rememver that ! yes this is sarcasm, and lack of context posting.. - I know you are doing the same tinkerbell :D:D

I agree on the ABS thing Secoh and fro.. at my murcott day my stock AE82 corolla (with rear drums) was stopping faster than any of the cars with ABS (commdores, magnas,a maxima- this was 1997 though) once I'd had a bucketload of practice... in the real world though I don't think there is anyway in an actual emergency that I could manage to stop the same way consistently, nor as easily..

luckily I haven't really had to use that skill on the road, since then, and I know in the one massive oh fark moment in the rally car that I've had at 100 + km/hr, I just stood on the stoppers and locked up, went up the bank and nearly rolled... luckily the only thing hurt was the car! but I doubt I would have helped myself much by threshold braking anyway- was going waaaaaay too fast...

200sxtc- my rally car is fairly brake challenged- stock gemi discs up front with DS3000's up front and drums @ the back.. on a 20 km stage even driving as slowly as I do these days, I can fade them after 15 km or so, but I never brake 'to the limit' either- I'm curious to see what they'll do on the track next month :oh:

that said I do tend to use engine braking - ie being high in the rev range in the lowest appropriate gear for the speed, so i can back off and have the car slow sigificantly without upsetting the balance too much, or I can accelerate and have all 40 gerbils chime in at once , as well as save the brakes a bit.


I agree with what everyone without a massive ego has said regarding emergency braking- you'll stop quicker and more consistently without engine braking cos you're 100% focused on that and steering if need be, not double declutching and changing gears...

Rowds

[Spac]

Well technically if you are at the edge of maximum braking and you let the clutch out to give you engine braking then you will lock the appropriate wheels and cause your stopping distance to increase.

...which assumes that the brake bias is correct, and that it hasn't been upset by the load, the tyres, the road, whatever.

In a REAL panic situation (which I've only ever had once in 11 years of driving, and probably nearly a million kays), then I forgot to push the clutch in.
In the multitude of other "oh shit, this is interesting" situations, I'm definitely a clutch-in kinda guy.

Having said all of that, there are a number of other things that make a difference - I do tend to run it back down gears, to keep the (RWD) car 'light footed' and easy to turn. I also mostly look at where I want to go, and never at what I'm trying to avoid.
Just depends on how much of a panic I'm in, whether I actually acheive it successfully or not.

[MickyD]

For the skilled people out there no ABS is better than standard shitty ABS any day

maybe shitty ABS systems, or ABS systems in older cars, but I've heard quite a few people who would know say that a good ABS system is basically unbeatable.