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Deburn
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Thanks dsbmw and moderato, I will though it sounds like these techniques are not required or dont matter that much with the tech thats in cars these days

dsbmw said:
For the person who asked what rev matching and double clutching is, I'd suggest you google it outside this forum. I'll offer a 2 cent, 2 min reply, but I'll likely get flamed for writing anything and you'll get lots of conflicting posts. In it's shortest explanation, to double-clutch, you shift from gear to neutral, momentarily release your foot from the clutch pedal, and step back into the clutch as you shift to the next gear. For rev matching, tap the gas pedal before releasing the clutch so that the engine's speed is close to what its load will be when you release the clutch. That is, the rpm's of the engine should be similar to the rate of turn of the selected gear that is being turned solely by the car's wheels while the engine is disconnected from the transmission. You pretty much do this when regularly working through the gears at moderate rates, yet those who're into performance driving will have to work more diligently at it when driving hard, particularly for instance, when cornering and not wishing to upset the balance of the car while down shifting by introducing an abrupt engine break. Yet, knowing that they'll need the lower gear after the turn, they're already on it when they exit the corner. Hence, the need for toe-healing the brake and gas, as they're simultaneously slowing down coming into the curve and need to rev match the engine. Double clutching is hardly ever done today, as the simplest manual tranny in a car (for big rigs, it's another story) has synchronizers that help engage each gear. Yet, together with rev matching, it was a way to help smooth the transitions between gears in older cars (pre 70's). However, if you have a very high mileage car and find it difficult to engage a gear, it's respective syncro is likely worn, and double clutching/rev matching will help enter the gear. I've never been into high end performance driving, but many of these techniques in their simple form I had to learn as a teenager having nothing other than my beat up bug in SF. The bungee cord type hand-brake cable was worthless in holding the car on a hill so toe-healing was a necessity. Moreover, the old 'match-box' tuned points and over stripped 10mm bolt that held the distributor in place only lasted a few hundred miles before losing half the power of the 45HP engine. Hence, if I was on 3rd gear and had to make a right turn and go up a modest hill, I'd either have to stop and go into 1st gear and stay there, or without slowing down too much, forcefully shift from 3rd to 2nd on the turn by double clutching and toe-healing to rev match and climb up at twice the speed on 2nd, at about 20mph. Those were the days…
 

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dsbmw said:
I noticed this thread went all over the map and after the first couple of replies, it never addressed the original question; it just demonstrated lack of definitions by some and poor reading by others......

Incidentally, those who claim that simultaneous braking while accelerating from a steep hill isn't necessary to prevent rolling back if one just knows how to release the clutch sufficiently before letting off the brake and stomping the gas might do well in defining "steep hill." To get an idea of what someone in SF (or Wellington, or other cities with *real* hills) thinks of "steep," consider going to the steepest street in your town. While parked, open a water bottle and fill a cup with straight walls up to half its diameter from the rim (e.g. if a mug has a 3" diameter, do not fill the top 1.5"). Now, very carefully open one of those awesome cup holders your car has, and place the cup in it as gently as possible. If you haven't already spilled water by now, you're not on a steep hill. You're still below 26 degrees; we have a few 30's around here. If you're above that angle, and can master the simultaneous brake technique, you could take a sip from the cup and drive forward without spilling any more. The sine of 30 deg = 0.5. .....

Wondering if this horse hasn't been beaten to death by now.
Yes, this thread went all over the map. Isn't that part of the fun? :) In an effort to continue the beating....

I am the first to agree that SF has steep hills, been there, driven there. We don't see much over 12% locally, unless we go off road. SF has several hills at 30%. Fillmore, quoted by another poster above, is steep, but one recent bicycle race graded that hill at 10% average grade, 18% peak grade. There are some 30% hills, I am sure. But that is still only 16 degrees, not 30 degrees. Also, the math may need adjusting in your otherwise excellent (and very graphic) coffee cup example. If you have a 3" diameter cup, and fill it within 1.5" of the top, and tip it, it seems to me that the spill point will be 1.5" rise over 1.5" run (since the run is half the diameter). This means spillage would result on anything over a 100% grade, aka 45 degrees. This is why coffee never spills when driving steady, only when braking or accelerating. Gotta say though, that the visualization was great.
 

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CC 330i said:
I'll throw in my 2 cents. Having visited SF on many occasions, I don't think using the hand "BRAKE" (correct spelling) ...
Ouch... Every once in long while the fact that English is my second language catches up with me! When it does, it typically happens with something that simple, but which happens to fall in an area in which I haven't done much writing before. Nevertheless, it can make one look quite ignorant. :eeps: :banghead: This is definitely the first time I've had to write about brakes in my life. :)
 

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Don't know how accurate this is but...

The Steepest Streets in the City
1. Filbert between Leavenworth and Hyde (31.5% grade)
2. 22nd Street between Church and Vicksburg (31.5% grade)
3. Jones between Union and Filbert (29% grade)
4. Duboce between Buena Vista and Alpine (27.9% grade)
5. Jones between Green and Union (26% grade)
6. Webster between Vallejo and Broadway 26% grade)
7. Duboce between Alpine and Divisadero (25% grade)
8. Jones between Pine and California (24.8 grade)
9. Fillmore between Vallejo and Broadway (24% grade)
(Source: San Francisco Almanac)
 

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Has anyone outside of SF figured out how to eliminate the "drive off assistant" aside from not pressing brake while stopped in first with clutch in?
 

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BMWCCA 149159
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To the OP regarding your ORIGINAL question.
If you don't like the feature get it programmed out. It is that simple.
This feature isn't just on manuals it is on all of the E90 series.
It will cost you to take it to the dealer to have this done but once done it is gone forever.
I am working the coding on our cars so I can modify the systems to suit my needs and hill assist is gone as soon as I finish...
 

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Not a real doctor.
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The way I normally drive, the hill assist doesn't come into play. On the few occasions where I want it, it seems natural and easy to engage it.

'Not sure what the big deal is.

And, yes, this has to hold the record for oldest resurrection.
 

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VIII
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That feature annoyed me at first as well, I never had a car with it before but now that I'm used to it, I love it! If you're on a hill, backing out of parking spot, etc., it holds the car for a couple seconds and allows you to get a nice easy engagement on the clutch. I've been driving MT my entire life and yes I've never needed it before but now that I have it, I think it's a great feature. If you really want the car to roll for some reason, just put the car in neutral and take your foot off the clutch pedal and the car will roll, or just wait the 3 seconds or so for the brakes to release and then the car will roll. The brakes release quickly once the car gets some positive torque going so, I don't feel it's ever invasive at all.
 
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