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IOwnCalculus posted:Do you weigh more than 80 pounds? Can you stand up while holding any weight at all? Congratulations, you can apply at least 80 pounds of force to the brake pedal. I weigh 85kg and yes if I was stood on a scale that shows 85kg. But think about how it's set up if you lift your self out of your seat. The wheel becomes your pivot point and the brake pedal is what your stood on. To exert the same amount of pressure you have to make sure your body stays still which means you have to lock your arms, and extend your legs. Even then your not directly above the brake so the effective weight your actually putting on the pedal will be reduced as it's on an incline. With your back against the seat all you need to do is extend your leg which would exert more force through the pedal as your locked in and can't move. Pictures would do this better justice and I'm sure someone more versed in physics would be able to explain it better than me.
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Feb 19, 2018 21:16
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IOwnCalculus posted:To be fair, it seems like learning just how late you can brake is one of the hardest things to teach yourself. Especially since the consequences for braking too late are far worse than the consequences for braking too early (assuming other drivers are paying attention). Even hard on a race track. Ended up showing a guy in my run group at the last race of last year that he was braking way too early - he had a lot more seat time than I did but I started figuring out he was leaving huge amounts on the table under braking, which means a trivially easy passing opportunity. ... I'm jonesing hard to get back on track this year, does it show?
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Feb 19, 2018 21:22
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I had my throttle get stuck half open before (engine back/misfired thru the intake, blew a chunk off the air filter, which then got sucked back in and wedged in the butterfly valve) and the engine was lurching/straining the brakes a little after I put it gear at a standstill after throwing it in neutral and slowing down. Only shifted it back out of neutral because it was banging on the rev limiter and in drive it was only doing 4 grand or so — which was plenty of "unintended acceleration" on a 30 MPH street. But even the brakes of a clapped-out subaru could hold its own engine so, yeah, speaking from experience, this is ridiculous.
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Feb 19, 2018 21:26
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Puddin posted:I weigh 85kg and yes if I was stood on a scale that shows 85kg. I wasn't disagreeing with you, my point is that generating 80 pounds of force with your legs should be trivial for anyone who doesn't need hand controls to operate their vehicle. mekilljoydammit posted:Even hard on a race track.  I did a couple sessions in a shifter kart once and the brakes on those are so absurdly powerful that I could not shut my lizard brain up to brake late enough. The few times I've gone autocrossing I know I've left absurd amounts of time on the track by being way too early / gentle on the brakes.
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Feb 19, 2018 21:28
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One major problem is that a lot of people have their seat too far back, and thus can't exert full force on the brake pedal. If your leg is completely straight when pushing the brake pedal, you're way too far back. I've seen people that have to completely straighten their legs and their feet, just to brake normally. When the seat is correctly positioned, you should still have a bend in your leg, even with the brake pedal fully pressed and jammed into the carpet. I used to have my seat too far back, until I did some evasive and braking tests to get cheaper insurance rates a couple of years after I got my license. I was fully stretching my leg and pushing myself into the seatback and up, instead of braking properly. After moving the seat forwards a couple of clicks, my braking lengths reduced dramatically. That taught me a lot about proper seating position, so now I have the seat relatively close to the pedals (so I can press them fully, without stretching), I have the seat back quite straight, and I have the steering wheel telescoped relatively close, so I can put both wrists on top of the wheel while keeping my shoulders in the seat. Think race car driver, instead of gangsta lean. And it's just so much more comfortable not having to stretch.
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Feb 19, 2018 21:32
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KozmoNaut posted:One major problem is that a lot of people have their seat too far back, and thus can't exert full force on the brake pedal. If your leg is completely straight when pushing the brake pedal, you're way too far back. I've seen people that have to completely straighten their legs and their feet, just to brake normally. When the seat is correctly positioned, you should still have a bend in your leg, even with the brake pedal fully pressed and jammed into the carpet. There's also your health at risk if you don't use a proper seating position, because the bend in your leg means you go from several months-years in physical therapy to just a few weeks. Obviously this is only under the right circumstances, but I wouldn't wanna take the chance considering how easy it is to avoid the more serious inury here.
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Feb 19, 2018 21:35
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If your seat isn't all the way back, how do you look cool/use the B pillar to protect you from crossfire?
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Feb 19, 2018 21:47
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IOwnCalculus posted:I wasn't disagreeing with you, my point is that generating 80 pounds of force with your legs should be trivial for anyone who doesn't need hand controls to operate their vehicle. All good man, got my wires crossed. Chances are everyone that claims they have a runaway are not good drivers to begin with and can't react accordingly. I recently got my truck license and though I considered myself to be a good driver, it's pointed out some very glaringly bad habits I've accrued over time. I'd highly recommend at least doing some lessons for a truck, it certainly makes you more considerate on the road.
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Feb 19, 2018 23:31
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Puddin posted:
Yeah, especially when dealing with grades.
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Feb 20, 2018 01:08
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C-Bangin' it 
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Colostomy Bag posted:Yeah, especially when dealing with grades. Puddin posted:I'd highly recommend at least doing some lessons for a truck, it certainly makes you more considerate on the road. I got my CDL when I was 18, just 2 years after I got my class C. Definitely improved my driving.
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Feb 20, 2018 01:20
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SEKCobra posted:There's also your health at risk if you don't use a proper seating position, because the bend in your leg means you go from several months-years in physical therapy to just a few weeks. Obviously this is only under the right circumstances, but I wouldn't wanna take the chance considering how easy it is to avoid the more serious inury here. I have the opposite problem. I can't put the seat dangerously far back in just about any car. OTOH, in a lot of cars, even with the seat all the way back, my knee is wedged between the steering column and dashboard with my foot just barely resting on the brake. I fear getting in a bad accident and having my loving thigh shattered.
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Feb 20, 2018 01:41
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Puddin posted:I weigh 85kg and yes if I was stood on a scale that shows 85kg. This is my Bonneville after a head-on in 2000. I weigh about 140kg. I was not wearing a seatbelt (fairly obvious from the steering wheel) and I pivoted upwards exactly as you describe. You can see the consequential effect on the brake pedal, which was 14-ga. steel.  Below is the car I replaced it with. Note the brake pedal. 
PainterofCrap fucked around with this message at 02:07 on Feb 20, 2018 |
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Feb 20, 2018 02:05
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I'm sure everyone in this thread is very impressed with how much force you think you can apply with your feet. I can leg press about 310, 320 lb and I'm not a big guy. How big is my e-peeny? Anyway it seems like a lot of people are missing a really key point here: with the throttle jammed wide open, your vacuum-assisted brakes have no boost. The clamping force has to come entirely from your feet. It's likely still possible to apply enough force to stop the car, but it will be several times more pressure than you've ever put on the pedal before. People might think they're already pushing as hard as possible when they aren't, because it feels like as much as they've ever done. Anyway anyway this is why you gotta know how to put your car into neutral, turn off the engine, etc. All those people with runaway Priuses could have stopped the car in seconds by bumping the transaxle into neutral and braking normally, but they panicked and hadn't practiced emergencies enough so they died.
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Feb 20, 2018 03:59
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Except all vacuum boosted brakes store more than enough vacuum to apply the brakes once, and have a check valve to not allow vacuum to bleed back into the intake manifold. Yes, they do run out, but there's easily one good application to a stop in there.
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Feb 20, 2018 04:27
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Sagebrush posted:I'm sure everyone in this thread is very impressed with how much force you think you can apply with your feet. I can leg press about 310, 320 lb and I'm not a big guy. How big is my e-peeny? God help these people if their car ever stalls out while moving.
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Feb 20, 2018 05:13
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Nocheez posted:I don't think there's a passenger vehicle out there that can out-accelerate its brakes. If your car is stuck going, holding the brakes down firmly will stop the car. I'm going to argue that bringing an average car to a complete stop from WOT (so no vacuum assist) with cooked brakes is going to be pretty drat hard to stop. The first time it happens to someone, all they'll be able to think of "OH poo poo BIG PEDAL". It's happened to me, I cooked the brakes on my F-150 when the throttle got jammed open (with a whopping ~130 hp), and took over a quarter mile to get it stopped (with smoke pouring off of the front brakes; throttle jammed WOT with the speedo pegged at 85 MPH). I've had it happen on a few other cars since then; it's a non-event on all of them, since I now know "stand on brakes/shift into neutral/let engine bang rev limiter like a 16 yr old virgin getting his first hand job/coast onto shoulder/do it smoothly all in one motion". It's a bit different if it's babby's first "OH poo poo". randomidiot fucked around with this message at 08:16 on Feb 20, 2018 |
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Feb 20, 2018 08:01
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Yu-Gi-Ho! posted:If it's something you've never dealt with, you're not going to calmly think "okay, shift into neutral, turn off the ignition switch, but not far enough to lock the steering, now stand on the brakes and calmly coast to the side". I've had the exact thing happen to me when I was 17 and yeah, I knew to put it into neutral and hit the brakes. I also had a friend start the car while it was in gear with no neutral safety switch about 15 feet away from my friend's car and had had the frame of mind to rip it in to neutral and pull the ebrake, from the passenger seat. It's people just straight panicking and not knowing what to do, I'm not saying I'm special, just that I didnt freak out when things went wrong. DiggityDoink fucked around with this message at 08:18 on Feb 20, 2018 |
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Feb 20, 2018 08:14
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I was 16 when it happened, and very, very dumb. I also drove the same truck home from school with a ruptured wheel cylinder one day, mostly using the parking brake to stop it.  The brakes on it were horrible to begin with.Wanna guess how I got my 88 Accord home when the timing belt let go about 1/8 mile from home?  (starter - no clutch switch on 3rd gen accords)randomidiot fucked around with this message at 08:20 on Feb 20, 2018 |
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Feb 20, 2018 08:17
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Yu-Gi-Ho! posted:I was 16 when it happened, and very, very dumb. I also drove the same truck home from school with a ruptured wheel cylinder one day, mostly using the parking brake to stop it. See, this is why I'm so thankful I had family and friends that raced dirt track when I was a teen. I got just enough wheel time to experience some goddamn amazing failures, and being in SUCH a high stress environment made it so that when poo poo happens on the road I don't even blink. Everyone needs a good high stress driving experience with failures. Teaches you a lot about yourself.
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Feb 20, 2018 11:52
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Yu-Gi-Ho! posted:I'm going to argue that bringing an average car to a complete stop from WOT (so no vacuum assist) with cooked brakes is going to be pretty drat hard to stop. This was literally answered two posts above you... And one good brake is conservative, there's usually enough vacuum for a second application at almost full boost. DJ Commie posted:Except all vacuum boosted brakes store more than enough vacuum to apply the brakes once, and have a check valve to not allow vacuum to bleed back into the intake manifold. Yes, they do run out, but there's easily one good application to a stop in there.
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Feb 20, 2018 13:03
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Yu-Gi-Ho! posted:I cooked the brakes on my F-150 when the throttle got jammed open (with a whopping ~130 hp), and took over a quarter mile to get it stopped (with smoke pouring off of the front brakes; throttle jammed WOT with the speedo pegged at 85 MPH).
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Feb 20, 2018 15:40
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Seat position chat: if you were driving a manual transmission, you'd already be sitting close enough to stomp your brakes correctly.
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Feb 20, 2018 16:01
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Yu-Gi-Ho! posted:I'm going to argue that bringing an average car to a complete stop from WOT (so no vacuum assist) with cooked brakes is going to be pretty drat hard to stop. Cooked brakes aren't stopping you very well even without a jammed throttle. Luckily it's not something that youre as likely to encounter on modern stuff.
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Feb 20, 2018 16:09
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IOwnCalculus posted:You still got it stopped. Yes it took a long time, yes you roasted the brakes to do so, but you got it stopped. You didn't keep going for miles and miles claiming you couldn't. ...whilst being able to make a phone call to the police, yet unable to kill the ignition or knock it out of gear.
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Feb 20, 2018 16:22
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spog posted:...whilst being able to make a phone call to the police, yet unable to kill the ignition or knock it out of gear. To be fair, there's a decent amount of cars on the road that don't HAVE an ignition. All you have is a stupid button that says gently caress you when you press it while moving. Sure, there's probably something you can do, like holding it down and sticking the gear selector up your rear end in a top hat, but most people don't know about that.
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Feb 20, 2018 17:46
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chrisgt posted:To be fair, there's a decent amount of cars on the road that don't HAVE an ignition. All you have is a stupid button that says gently caress you when you press it while moving. Sure, there's probably something you can do, like holding it down and sticking the gear selector up your rear end in a top hat, but most people don't know about that. They all have a "force power off" but it is a valid complaint that you have to read the manual to know what the procedure is. No one reads that poo poo when they buy their car and they sure as poo poo aren't gonna read it going 100 mph down a highway freaked out they can't stop. Just another bullet point on the list of things that manufacturers gently caress up when trying to cram new tech into a car.
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Feb 20, 2018 17:54
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Every car allows you to go into neutral at any time.
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Feb 20, 2018 17:55
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Everyone should just drive 911’s so they can throw it into neutral and kill the ignition at the same time.
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Feb 20, 2018 17:58
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And, in fact, makes neutral the default detent on nearly every shifter. On column shifters, neutral has the deepest detent in both directions, meaning that even if you randomly slap it, it'll "rest" in neutral. You can pull the Prius shifter from any "point" (I know it's self-centering) towards the column and it'll go neutral. Even Chrysler's dumb-as-gently caress knob shifter has 16 degrees of arc for all gears but 21 degrees of arc for the neutral detent, with a deeper groove in the detent ring to make it the most easily found setting. Every car with a stick shift I've had lets you drag it into neutral without clutching.
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Feb 20, 2018 18:00
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Feb 20, 2018 18:04
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Sounds like someone needed more training, but he got railroaded. Loco.
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Feb 20, 2018 18:12
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A pile of dry brush seems like a horrible place to park your flaming locomotive.
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Feb 20, 2018 18:16
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Metal Geir Skogul posted:Every car with a stick shift I've had lets you drag it into neutral without clutching. Only if you let off the gas... Wide open there's force on the gears and it's not gonna go into neutral.
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Feb 20, 2018 18:23
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chrisgt posted:Only if you let off the gas... Wide open there's force on the gears and it's not gonna go into neutral. I find in my work truck, its the opposite. Especially going downhill. I have to goose it just a bit to pop it out of gear without the clutch. Mind you thats when I'm coasting.
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Feb 20, 2018 18:28
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wesleywillis posted:I find in my work truck, its the opposite. Especially going downhill. I have to goose it just a bit to pop it out of gear without the clutch. Mind you thats when I'm coasting. The point is that you create some lash in the transmission while loading the shifter, it works either way Pretty much how you ride a motorcycle... clutch only needed from a stop or if you're trying to fan that clutch into a corner on a bike without a slipper
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Feb 20, 2018 18:43
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https://www.youtube.com/watch?v=zAlNrtcPCLw
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Feb 20, 2018 18:46
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wesleywillis posted:I find in my work truck, its the opposite. Especially going downhill. I have to goose it just a bit to pop it out of gear without the clutch. Mind you thats when I'm coasting. If you have load on the transmission either via acceleration or deceleration, it won't pop out of gear into neutral. You have to reach a point where no load is being transferred to or from the engine, then the gears won't have force on them, and it'll go to neutral.
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Feb 20, 2018 19:02
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You're just not trying hard enough.
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Feb 20, 2018 21:28
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Apparently you've never driven a car with a hosed up gear linkage. Always fun when you suddenly lose power to the wheels and your tach shoots up a few thousand rippums
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Feb 20, 2018 21:38
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The Door Frame posted:rippums I felt like I was the only one who said this aloud but I’m seeing that I was wrong!
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