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Comment by rwbt | Hacker News Reader

A lot of annoyances, needless complicated door handles, buggy software. But this made me smile and the car enthusiast inside me is ecstatic.

> "This car is a joy to drive on Angeles Crest Highway, and I don't say that lightly. Angeles Crest is a famously demanding road that winds up into the San Gabriel Mountains north of Los Angeles. You need brakes, power and a taut, balanced chassis to do it right. The Model 3 has it all. Body roll is minimal, the brakes don't complain, the steering is gratifyingly precise, and there are gobs of instant torque on tap. Plus, the regenerative braking function means you use the actual brake pedal less often.

> "It's a new kind of fun to lift off the throttle ahead of a corner and realize you've already scrubbed enough speed without even touching the pedal. After my drive, a friend of mine asked me how the Model 3 compares to the current BMW 3 Series, and I told him I'd rather have the Tesla. He laughed. I wasn't kidding."

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“you need brakes”

According to the latest Consumer Reports test the model 3 failed pretty hard in that department:

http://www.thetruthaboutcars.com/2018/05/pump-brakes-consume...

That was one vehicle. The first test was fine. Subsequent tests were not. It's pretty clearly a flaw in the brakes of that particular vehicle. If CR wants to generalize from that fine, but it's not doing a service to its readers.

I will disagree, I think they are making people aware of a potential problem, if indeed this is only with some cars, as most people won't know just by driving if their car's breaking is per the specs.

This thread is an excellent example of how people will over-interpret such a warning.

It says they borrowed a second car from a private owner to double check and had the same results.

They tested on 2 model 3s with "almost identical" results. https://www.consumerreports.org/hybrids-evs/tesla-model-3-re...

> That was one vehicle.

From the Consumer Reports article[1]:

Because we saw some inconsistency in the braking performance, we got a second Model 3 (a privately owned vehicle that was loaned to CR) to verify our results. CR has tested second samples in previous situations to double-check our findings.

...

CR’s experience with the Model 3’s braking is not unique. Car and Driver, in its published test of a Model 3, said it noticed “a bizarre amount of variation” in its test, including one stop from 70 mph that took “an interminable 196 feet.”

“I’ve been testing cars for 11 years,” Car and Driver Testing Director K.C. Colwell said in an interview with CR, “and in 11 years, no car has stood out with inconsistent braking like this. Some trucks have. . . . It was just weird.”

[1]https://www.consumerreports.org/hybrids-evs/tesla-model-3-re...

Well it looks like brake issue can be solved with a software update [1] in a few days. Which is not too surprising since brakes are a known technology.

[1]https://electrek.co/2018/05/22/tesla-will-update-model-3-fir...

It's because they're a "known technology" that it's rather surprising that Tesla managed to screw up their ABS system in such a dangerous way. If there has been an analogous failure with either traditional Bosch ABS systems or the Toyota systems that integrate with hybrid and electric powertrains - both systems have been around for decades - I'm not aware of it.

Not that Toyota hasn't had other sorts of firmware problems...

True, it is surprising that Tesla seems to have a bug in such a known technology. But also because it is such a known technology it would be equally surprising if there wasn't an easy fix for the problem and it turns out there is. A tempest in a tea pot.

> But also because it is such a known technology it would be equally surprising if there wasn't an easy fix for the problem

There is no logic to this belief of yours whatsoever. It was an easy fix because it's online-updateable firmware, not because it's "known technology."

> Body roll is minimal

There are a couple of problems with the obsession for flat cornering.

One is that its uncomfortable for people in the car, particularly passenger, who are pushed sideways into the seat-bolsters and side panels.

More importantly is when lateral grip finally breaks there is no warning to the driver with a cocked wheel and gentle progression: it just lets go.

As a counter-example Mazda have always engineered some body-roll into the Miata / MX-5 so that it's fun and communicative in corners.

The 3 is so bottom-heavy that it could be that it naturally corners flat.

I'm not sure I understand how having a flat body roll is worse than normal, in terms of passenger tiltiness.

Ideally, the car would bank, rolling opposite. Then the force of the turn would push you into your seat, rather than out of it. But I'm probably misunderstanding something.

> More importantly is when lateral grip finally breaks there is no warning to the driver with a cocked wheel and gentle progression: it just lets go.

This honestly depends on the tires. A lot of performance tires lose grip very gradually. Don't know what tires the Model 3 comes with, but with a good set it shouldn't be an issue.

> As a counter-example Mazda have always engineered some body-roll into the Miata / MX-5 so that it's fun and communicative in corners.

I daily drive an MX-5 and the body roll drives me nuts. If you ever drive a modded Miata or an S2000/BRZ or a Porsche Cayman it'll be very apparent how their lack of body roll gives superior driving dynamics while still being very compliant. Not saying Miata is a boat, but it's overly wallow-y for a car of that size.

> One is that its uncomfortable for people in the car, particularly passenger, who are pushed sideways into the seat-bolsters and side panels.

Body roll is going the wrong way to make it more comfortable. The roll is in the same direction that the passengers are being pulled, which makes the passenger impact worse as gravity adds to the pull as the car tilts. Contrast with a banked curve, which is essentially reverse roll, and is more comfortable because much of the force is directed "downward" into the seat.

It's a new kind of fun to lift off the throttle ahead of a corner and realize you've already scrubbed enough speed without even touching the pedal.

That sounds similar to the feeling of driving a bus or other heavy vehicle with a retarder and/or Jake brake.

Sounds like driving a manual, actually. You just use the brakes a lot less.

Except with a manual, you're reducing the lifetime of your clutch, while with regenerative brakes, you're saving energy.

I find that one-pedal driving makes me much more mellow: I play a game where I try to never have to use the actual brakes.

Disclaimer: my first clutch lasted 120,000 miles.

> Except with a manual, you're reducing the lifetime of your clutch

Huh? How is engine braking (or, for that matter anything) on a fully-engaged dry clutch going to reduce its lifetime?

Well, that's what people tell me, and a quick google shows that the Internets have a huge debate over the issue. So I'll just say that I'm not an expert, but I still love one-pedal driving.

Edit: from the huge number of downvotes my previous comment is getting, apparently many HN users think they know the answer!

The huge number of downvotes should probably indicate to you that what you stated as a matter of fact is incorrect[1].

It's not necessarily that HNers think they know, even though I'm sure we do! :), it's that it's pretty clear that you didn't know but made a statement as if you did know, with no substantiation. Sadly, as it turns out here, it was based on "some guy somewhere said", which is a much-maligned standard of knowledge on HN.

BTW, I suspect the downvotes for this comment are for the combination of basically admitting that you're relying on hearsay and that, attempting to research the matter further, you were shocked (shocked!) that there were people arguing on the Internet and that was the end of the matter for you.

[1] or a matter of opinion, but this is an engineering topic, which, on HN, is generally pretty comfortably treated as fact.

It won't. Unless the clutch is damaged and slipping, or slipping because your foot is resting on the pedal, it's all locked together and it's not going to wear. You will always cause a bit of wear to the clutch while shifting, but that's a different conversation. (with all the rev matching that the newest manual transmissions will do for you, I wonder if replacing clutches during the normal lifetime of a passenger car will become a thing of the past, but it's too soon to say for sure)

Well, if most cars become electric and have one gear, it's safe to say that your question will be answered "yes".

That was, essentially, my point. (Foot resting on the pedal heavily enough that it slips doesn't count as fully engaged, of course).

> I wonder if replacing clutches during the normal lifetime of a passenger car will become a thing of the past

My gut says that clutches wear far more from starting at a dead stop than from any gear changes in motion, so taking rev-matching out of the hands (foot) of the human won't make enough of a difference.

That's an interesting question. There's a lot more time spent slipping the clutch getting the car started, but there are higher RPMs and more power being transmitted through the partially-engaged flywheel and clutch during some of the other shifts. But yes, intuitively, it definitely feels like starting the car is when most of that wear happens, and if I had to bet I would bet that's right, at least during everyday driving.

> there are higher RPMs and more power being transmitted through the partially-engaged flywheel and clutch during some of the other shifts.

I'd argue that, if that's the case, one isn't doing it right. Ideally, there is zero RPMs difference during disengagement and engagement during routine gear shifting.

One doesn't even need the clutch, if one is good enough at rev-matching. I expect the risk of damaging a gear or synchro makes this a bad idea in general practice, but it can help get a clutch that no longer fully disengages to a mechanic without a tow-truck, something important in my younger/poorer days.

I play the same “game” (not using brakes). The extra clutch wear happens because you down shift to increase engine braking. You rev match (blip the throttle) so the car doesn’t jerk when you do this.

I’ve got 212K miles on my original clutch (a 2007 BMW 3 series) so the wear isn’t too bad.

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