Re: Braking in New Handbrake shoes and Disks

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In my experience, most vehicles have brake pedals that are too far apart or at very different heights to make heel-and-toe possible or comfortable to use.
It's not that it's a big deal to do heel-and-toe but the handbrake works much better.
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Well, the sedans I drive are BMW's and I haven't had one in quite a few years that wasn't set up nicely for heel & toe. I think I have to go all the way back to the E21 before I hit upon a BMW I have owned which had pedal placement less that suitable for heel & toe. The lateral spread was good, but the pedals were placed to far above the floor pan. I cannot speak to whatever cars you drive, but I thought you were an E39 owner. My E39's were superb in this regard, and have been roundly praised in the motoring press for their pedal placement on this point.
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Unlike the 3er the 540i doesn't work very well with heel-&-toe technique. Firstly, the pedals are not well-located. This issue has been debated thoroughly on the ROADFLY.COM newsgroup so you can look for yourself. Most people seem to roll their ankles to the left and use the ball of their feet. But it doesn't always work. I place the heel of my foot on the brakes and point right towards the throttle with my toes. My feet are otherwise too narrow to bridge the pedals with a rolling action. All of this can be vastly improved with some modifications and new pedals. Unfortunately, there's another problem.
The other unfortunate part about the E39's design has nothing to do with the pedals. It's the electronic throttle control. This issue has also been debated on the ROADFLY.COM newsgroup. The throttle-blipping response in the 540 is severely muted because BMW chose to design the throttle to allow it to obtain a more favourable EPA gas mileage rating. Blipping the throttle in the 540i is very tricky business. It isn't predictable because it's not mechanical - the electronics decide if they should respond under a broader set of conditions, of which I have little clue to. It's better in the I-6 models as they seem less restricted by this throttle design but even they are not as responsive as older BMWs. Which E39 model do you drive?
FWIW, because I trained on a 3er I sometimes heel-&-toe instinctively in my 540i but I don't bother to do it consciously because the throttle response to blipping is so unpredictable - no sense unsettling the car when the revs don't match anyway. In any case, the torque from the V-8, post-corner, is so abundant that I can afford to take my corners a bit slower than I would have in a 3er. I just try to drive smoothly with a reserve of power in case I have to maneuver out of harm's way. I don't race on the streets.
If you want to debate what I say I would prefer to direct you to the pros and other people on ROADFLY.COM. Otherwise, it just becomes an issue of my opinion against yours. I have said all I care to on this particular topic. Here's a good webpage by pros on heel-&-toe:
http://www.nasaproracing.com/hpde/heelandtoe.html
"...Heel Toe cannot be done smoothly unless two things are done:
1) The pedals must be matched. Normally this is done by adjusting until the brake and throttle are even in height, when the brakes are pressed on. The pedals must also be properly spaced. In my car it required adjusting and bending the gas pedal until I got the match I needed. In many cars, the pedals have some range of adjustment, making the process easier. One thing to remember, as you adjust the gas pedal, make sure that there is a mechanical stop for the pedal. If you rely on the stops in the carburetor or injection system to stop the motion, you will probably bend or break something as you try to squeeze a couple more horsepower out of the pedal. Also, make sure the linkage allows the butterflies in the carburetor to be fully open when the pedal hits your mechanical stop.
..."
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It's interesting that you and the Roadfly mailers find a difference between the 3 and 5 pedal location and setup. Because there is none (between the e46 and e39) the E60 is different from the E46, but the E90 will be exactly the same as the E60). Good ahead, check it out. Put one car right next to the other and check out location, center and disparity between pedal edge distances and you will find that BMW uses the exact same pedal setup between the two cars. It wasn't like this before, but starting with the E39/E46 BMW used the same series of measurements between each car's pedal setup.
Really, don't take my word for it. Take the time and check out the two cars side by side. I imagine it will surprise you.

Not for me, never has been, and not for any magazine I have ever read (not that I have great respect for magazines but I imagine they are as reliable as Roadfly when it comes to supporting cites). The entire E39 line-up was renowned for the throttle tip-in and the control it allowed. Neither of my e39's behaved anything at all similar to your discription. In fact, I believe of all the things people complain about in the E60, the thing they most often miss, particularly American commentators and reporters, is that the throttle tip-in on the 545 has fallen far from the superb 540.
This is my single greatest disappointment with the new Hooydonk cars. BMW's famous, renowned throttle tip-in has for some reason been abandoned for muddled technology and computer mapping. I have been told it is even worse in the auto tranny cars because the mapping in the transmissions is equally muddled so you get 2x's the issue.

It is an opinion issue between you and me. Comments on Roadfly don't supercede my own experience of 7 years with E39's. The throttle control is splendid and the pedal setup superb. There's just no way around that other than the individual physical parameters of the human driving the car.
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I don't think you would disagree that the 3er has always been more lively to drive than the 5er. If you dig a bit you will also find the E36 to be a better driver's car than the E46. The E46 is widely considered as somewhat of a disappointment - too heavy and bloated with electronics.
I used to own an E30 and the difference in handling and ease of use between it and the E39 was incredible. However, the E30 was not as comfortable on long trips and I needed a car that can do regular 5 or 6 hour drives without causing any fatigue.
Some of your comments about the E39 and the 540 appear contrary to general opinions and my own experience. The I-6 versions of the E39 are way easier to drive and much more of a driver's car. The 540 has shortcomings with its clutch, throttle and steering. Still, I like the 540 better because it's more effortless on the highway and more of a challenge when I feel like playing. Have you heard of an item called the CDV?
I've only tested a Steptronic 545 so I can't make a direct comparison but if you think the tip-in of the 540i is great you should try the tip-in of the 6-speed E60 530i. It is astounding by comparison. In any case, I was not referring to tip-in in my earlier post. I was referring to blipping the engine to rev-match when exiting a corner. Since the car is in motion and the engine is already at speed, the electronic throttle does not behave in the same way as when you are at rest or under different conditions.
I do not like electronic throttles. The mechanical throttle of my E30 was immediate and always responded in exact doses to input - heel-&-toe rev-matching was a joy and a snap. The only downside was the twin-mass flywheel. BMW did not always use a twin-mass flywheel? I also had that.
I am not trying to disprove your own success with your BMWs but I am just pointing out that other people have problems with the E39, especially the 540 clutch and throttle. The tips on pedal placement from the pros is just what it is - good advice on how to set up the pedals for heel-&-toe. Whether it is relevant to you depends on how those suggestions match the pedal placement in your cars.
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As a matter of full disclosure, I have the M50 motor. I have no idea what this does to the comparison, but I suspect not very much.
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In US form, the M50B25 (like the one in my '91 525i) makes 189HP@5900rpm and 181ft-lb@4700rpm. I believe that the 280, above, is a typo, or is the metric newton-meters figure (and the 440 figure has to be wrong, too.)
Floyd
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I believe that the 280, above, is a typo,

Ooops... my bad. That is a bit high isn't it. ;-) Yes the web site I was quoting the specs from was in nM not ft/lbs.
-Fred W
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Jeff, the M50 design was used in 2.0 to 2.5 L motors. The M52 design was used for engines with 2.0 to 2.8 L displacement. I suspect your E36 was a 2.5 L model. IMO, it's one of BMW's best engines.
But you're right though. This is moot to Fred.
What may be more relevant, at least to Fred, is the comparison of M52 and M62 engines. He is trying to point out an error in my previous gut-feel ballpark assertion that the M62 engine would be putting out at least twice the torque of an engine in any regular E36 in a hill start - just a technical point, not really at the core of our debate.
Here's my answer:
I looked up the torque curves for the latest M52 engine - the one in the E39 528i - so it is likely identical to the one in the latest E36. I also looked up the M62 engine's torque curve. I'm not sure if it's the one with VANOS - it shouldn't be because that engine is the M62 TU. Anyway, here's what I found:
ENGINE Nm @ 1,000 rpm @ 2000 rpm @3000 rpm ---------------------------------------------------------------- M52B28 ~125 215 260 M62VB44LEV ~295 ~390 ~420
RATIO 2.36 x 1.81 x 1.62 x
Fred seems to have quoted maximum engine performance figures for the respective engines. That's not relevant to our debate because neither of us would use our engines at that level for starting on a hill.
What is relevant is each engine's performance between 0 to 3000 RPM, the figures I actually suggested in my earlier message. As you see, the torque curve differences of the two engines between 1,000 RPM and 3,000 RPM are between 2.38 times to 1.62 times. In fact, if you average the two numbers, the result is exactly 2.0 times. I didn't cook the numbers - you can fetch the information off the AC Schnitzer website. Here is the URL for engine specs:
http://www.acschnitzer.com/englisch/index.html
So I think the point I made was a fair one, don't you? The idea was simply that when you drive a much heavier car with so much more torque the resulting moving mass is more difficult to control if you do not blunt the momentum with some sort of gradual braking force. That is why I use the handbrake in the E39 - it makes the car behave in a smooth and predictable manner and reduces wear on my clutch / flywheel.
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rpm

I would suggest that as a practical matter, driving in city streets, the torque and weight and control issues would be pretty much moot. That is, I can't imagine - without actually sitting in the driver seat - that I would personally use a different technique in my driving style at a standing start on a hill.
I don't think the "blunt force momentum" would be significantly different to the extent that it would cause me to change my behavior and style. Certainly, on a closed course in balls-to-the-walls racing, the differences would be huge, but when trying to get the car moving in traffic without damaging the nose of the car I was driving or the car immediately behind, I am not sure how the blunt force would come into play.
I hold my car with my right foot on the brake pedal. When my turn to proceed comes along, I let the clutch out just a little so that it just begins to grab but not drag the motor down to stall speed, then I take my foot from the brake and apply the gas and proceed to release the clutch so that my car rolls up the hill. I never even begin to do any of this until I am sure that I can proceed, this prevents protracted periods - or any period - of using the clutch to keep my car stationary. If I don't want the car to move, I apply the brakes.
If I felt the need to use the parking brake as a hill holder, though, it would easily perform that task. The entire discussion arose out of my suggestion that the parking brake is intended to keep a stationary car at rest, it is not designed for nor does it function well to bring a moving car to a stand still. Whether or not I use the parking brake as a hill holder says nothing about whether or not it can actually perform that task. As a hill holder, the parking brake would be called upon to keep a stationary car at rest, which is precisely what I maintain it can do.
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In fairness to our Euro friends though, their perspective in many cases is premised upon the reality that they can get some pretty weak-willed cars, and it will matter to them in greater degree than it does us, here in "chaotic" America, how weight and torque affect their driving techniques (in this case moving up a hill from a standing start). Also, there seems to be a homogenous aspect to how everyone in say, Britain, drives, because they all have to pass some pretty rigorous testing to gain a license )I have a friend I dive with who's daughter applied to take the test and was given a testing date 13 or 14 months later). While here in the states we'll let any blind-as-a-bat idiot behind the wheel as easily as we will a superb driver, like me. Couple that with 50 different driving test across the land and you end up with more of Michael's "chaos" :^)
I tend to agree with you Jeff. I don't use my handbrake for holding the car still while I move to accelerate up a hill either. Nor do I think these guys who are proponents of this technique actually need to employ it. They can negotiate a hill without this crutch if they want to. More than likley I think this about driving in a manner that saves wear on certain auto components. And my individual experience is that Americans are more "brutes" to their cars than most people around the world.
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Jeff, what I said was that it is harder to stop a heavier car that has been thrusted forward by a more powerful engine than it is to stop a lighter car moved forward by a smaller engine. Small, light cars are easier to control. The difference is critical when you maneuver the bigger heavier (EXPENSIVE) vehicle in tight places - you need to adopt a finer touch.
I know people can feather the clutch and throttle to start on a hill. Some people don't think it's a big deal to use the clutch in such a fashion. However you can't do that successfully under the situations I pointed out. Why don't you go on Lombard Street and see if you can avoid rolling back 3 or more inches without using a handbrake? I was in a German town called Erlangen last Fall and the ramp to the small old-fashioned hotel's indoor parking lot was about the Lombard Street grade or a bit steeper. A person can probably get vertigo just looking down that ramp. When I reached the bottom I found the door wouldn't open. I was in a 6-speed manual Mercedes SLK and it had just been drizzling. Luckily the car had a good handbrake. The SLK wasn't heavy but it was brand new and the metal garage door was inches from the hood. A very similar situation happened to me in my 540 at a downtown condo in Toronto a few years ago.
Finally, if you had used the handbrake you would never have bumped the guy behind.
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<snip>
No need to get testy, Michael. Let's try and maintain just a touch of civility in these pedantic discussions, eh? If your point was the 8 cylinder had more torque at low rpm you should have just said so. But that wasn't what you said, and hence my input pertaining to peak torque output, which is what is generally what is specified about an engine.
But to get back to the point of your discussion, I do see your point about the weight, but I fail to understand why a car with higher torque would be *harder* to start moving on an uphill stop. If anything an engine with higher torque would be better at this, no?
-Fred W
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Fred, sorry if I sounded testy but even you may find it irksome if other people interject in a mistaken fashion and seemingly throw the discussion off in a tangent.
You may have missed the part where I told Jeff "...Jeff, you forgot something - you don't HAVE a manual transmission 2-ton car that develops over 300 lb-ft at 3000 rpm.". So you see, my point was that, in the example of my car, it does have way more torque at low revs. And as I will explain below, that can present a different sort of problem in hill-starts.
As for the issue of more torque being an aid in hill starting - I agree. However, just starting on a hill wasn't what I was discussing - controlling the car after it starts WAS.
What I said was that BECAUSE a torquey engine would accelerate a heavier mass like the 540 in an aggressive manner, it makes it more awkward when you are pointing up on a hill with the car in front not that far away. Unless you feather the clutch or the handbrake, you'd have to stomp on the foot brake to avoid bumping the car in front.
The 540 has a fussy clutch release action and you have to sort of "prime it" with some revs to get a smooth release and even more so as the grade on a hill adds resistance to the drivetrain (on level or declined ground you can easily start in 2nd).
So, if you are only using the foot brake, the car will tend to lunge forward in such situations unless you feather the clutch or the handbrake. If you want to feather the clutch in such a heavy car then your right foot must dart for the throttle, making a smooth take-off even harder. IMO, trying to "suspend" a heavy car with a torquey engine mid-way on a steep hill is a very bad and unnecessary thing to do. It's much better to wear the handbrake lining.
And in addition ...as Jeff has himself admitted (when you mis-time swapping the footbrake for the throttle) your car can roll back too far and bump the guy behind. It is quite annoying to have someone in front bump your car just because they insist on not using the handbrake. While hill-starts are not the regimen in many towns, taking too many such liberties do add to the likeliness of "road rage".
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