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View Poll Results: Do you rev match?
Yes 85 65.38%
No 12 9.23%
Sometimes 33 25.38%
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      11-10-2009, 03:33 PM   #23
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I rev match most of the time, but as was mentioned earlier, you're ARE NOT hurting your car by not doing it during normal driving. And by normal, I mean you're slowing down at a reasonable rate, you're no where near the limits in a turn and making a hard downshift to lay the power on as you exit, and you're not skipping gears.

The ratios on these cars are pretty close together anyway, so unless you're really pushing it, or going from 6th to 3rd, you're not doing drastic RPM changes.

Since the "brakes vs. clutch" wear issue has come up, I'm going to throw my $.02 in on that as well.

When you downshift a car, you're putting the compression of the engine against the weight of the car. The forces involved aren't even close to what the clutch is designed to withstand on a regular basis, which puts the power of the engine against the weight of the vehicle. On a certain level, yes you are adding to the wear of the clutch, but for typical street driving it's minimal, and it's not a good reason to avoid engine braking altogether.

Also, the guy who said you should take off in second gear, that one's just flat out wrong. To minimize wear on the clutch you should be pulling out in first gear. That's were there's the most mechanical advantage, and that's where it's easiest to match the engine RPM (which should be just above idle) to the input shaft speed on the transmission (which is stationary). Pulling out in second gear requires higher RPM, and it also requires you to slip the clutch longer until the input shaft matches them. Doing it isn't going to kill the clutch instantly, but it WILL reduce it's usable life.
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      11-10-2009, 03:58 PM   #24
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Ive noticed its easier with the M button on
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      11-10-2009, 05:20 PM   #25
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Unless on the track I think 99.9% of people won't bother and of the other 0.01%, seriously guys, get a life.
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      11-10-2009, 05:27 PM   #26
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Originally Posted by footie View Post
Unless on the track I think 99.9% of people won't bother and of the other 0.01%, seriously guys, get a life.

Get a life cuz people rev match? Some people drive their cars like they are intended I guess.
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      11-10-2009, 06:04 PM   #27
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For what it's worth, the guys on Car Talk said the appropriate way to slow is not to down shift all the way through the gears, but to basically just coast/brake with the car in gear until you get to low RPMs, then depress the clutch and brake the rest of the way to a stop. It may be worthwhile to downshift once into something like third if you are coming from high speeds and a high gear.

Take it for what it's worth. Obviously this would be for "normal" everyday driving.

I would hope that no one would advocate downshifting all the way through the gears, that is just silly on a practical level...
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      11-10-2009, 06:27 PM   #28
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I had to teach myself how to drive stick, but in the process I read a LOT of artciles and watched a LOT of youtube vids. It was pretty apparent to me that rev matching is something that a good manual driver will learn to do. You can get away with not knowing how only for so long.

I think where rev-matching is most useful in daily driving situations is when you come into a 90-degree turn where you have the light and therefore do not have to come to a complete stop. If you don't rev-match, then you basically have to slow down to a speed where your RPM is low enough that you can shift into a lower gear (ie 2nd gear) without feeling the car jerk, which is probably around 15 mph or so, then re-accelerate all the way up once you complete the turn. On the other hand, if you know how to rev-match, then you can shift into 3rd or 2nd gear without having to slow all the way down to a near stop, AND do so without making the car jerk on the downshift, so that it takes a lot less time to make the turn. Another time that rev-matching is useful is as other people mentioned, when downshifting to pass on the highway. Without rev-matching, you get that nasty lurch. Again these are real-life, practical driving situations. If you never learn how to rev-match, then yes you can still be a capable, safe driver, but you'll basically be a granny behind the wheel.

For those who do not know how to rev-match, you just have to try it and practice. Over time you will get it. I had to learn on my own, and even I was able to get it. The rule of thumb is to rev up about 1,000 RPM for each shift down. So you will want to depress the clutch, rev up 1,000 RPM while shifting down a gear, then roll off clutch. With a little practice, you will be able to do it by feel without even looking at the tach. Believe me, you will enjoy driving stick a LOT more once you figure it out!
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      11-10-2009, 07:03 PM   #29
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More fun + smoother ride + more control + faster acceleration when you need it = win!

The most practical places I use it is for highway merging/passing, and when you're going uphill, and the cars in front of you slow down for whatever reason, and you need to get into the lower gear and prevent dying up the hill. Even when you're driving up a road that gradually turns into a steep uphill, it's useful. That, and I don't like my passengers looking like a bobble-head and thinking I can't drive. =]

I taught myself how to drive stick and to rev-match, and at first it really seemed impossible to get it right, but like everyone said, it becomes second nature. It all depends how fast you're going at the time, and which gear you're going into. The higher the speed and the lower gear = more blip.
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      11-10-2009, 07:49 PM   #30
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Quote:
Originally Posted by ChrisV View Post
How long have you been driving? With modern synchros it's simply not necessary unless you are racing and downshifting. Street driving, there's simply no need to shift faster than the synchros can handle. The trans will still last forever and it's not jerky at all.

Now, if I'm in an older car with worn synchros, then yeah, rev match every time (in fact, I've had to drive a couple cars that the clutch was so bad that I had to shift wiothout using the clutch, requiing careful rev-matching to get teh car to it's destination).
What you're saying makes no sense. If you downshift into a lower gear without rev matching the car jerks when the revs shoot up. It has nothing to do with synchros, it's gear ratios.

And the "brakes vs. clutch" thing makes even less sense. Now you're talking about engine braking, not rev matching.

it's like you guys are throwing around a bunch of terms without understanding what they mean.
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      11-10-2009, 08:19 PM   #31
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ok i gotta ask rev match?
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      11-10-2009, 08:58 PM   #32
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I rev match better than anyone else. M6 has auto blips
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      11-10-2009, 09:59 PM   #33
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Wow - this is pretty much a really embarrassing thread for the entire BMW enthusiast community.
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      11-10-2009, 10:08 PM   #34
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Quote:
Originally Posted by Nikolas View Post
Wow - this is pretty much a really embarrassing thread for the entire BMW enthusiast community.
Naw, plenty of n00bs drive BMWs. What % actually drive a manual? Like 11%? Yea.

FWIW, any time you use the clutch you are using the clutch. A clutch is a wearing item in your drive train; it just happens to also be the most expensive wearing item in the car. I prefer to use the brakes because like the clutch, the brakes are a wearing item, however they are a heck of a lot cheaper to replace, even accounting for longevity. When coming to a stop, depress the clutch, modulate the brakes, come to a complete stop. Release the clutch into 1st gear when it is time to proceed. QED.
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      11-10-2009, 10:27 PM   #35
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When I owned my 6speed GTO, I always rev matched unless I was using the clutch as a break to combine engine braking with regular braking for more barking power.
I would do this once in a blue moon (use of such heavy engine/clutch braking).

Otherwise, I don't see how it's possible to go from 6th gear at 2k RPM to 5th gear 2.5k RPM without there being a jerk....unless you are riding the clutch out slowly which would obviously take longer.

However, I also rev matched a lot because when I downshifted it was for more power, so my downshifts would be from 5th to 3rd for example, and this would be at least a 1k RPM difference which would be very jerky unless I rev matched.
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      11-10-2009, 11:14 PM   #36
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Quote:
Originally Posted by Nikolas View Post
Wow - this is pretty much a really embarrassing thread for the entire BMW enthusiast community.
Please, do tell. I can point to more embarrassing threads.
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      11-11-2009, 12:13 AM   #37
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Quote:
Originally Posted by Nikolas View Post
Wow - this is pretty much a really embarrassing thread for the entire BMW enthusiast community.

Shit, I wasn't aware you had to be a pro on the MT to purchase a BMW. Like I said, first manual car i've owned (not driven) and in some cases i'm thankful for that as it's a pretty forgiving car. Have had the car about a year now and haven't stalled it...well...for about a year now!

Anyways i'll leave you to better things - I would imagine a MT pro as yourself has multiple women to please on a pretty consistent basis
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      11-11-2009, 12:14 AM   #38
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Having my car for 5months now (1st time manual) I rev match 95+% of the time.
I only started rev matching about 6 weeks ago. Im still getting use to matching the rpm tho. Sometimes its higher, some times its lower but when the rpm is perfect i get such a good feeling Rev matching became a habit tho. I do it every time i down shift.
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      11-11-2009, 01:53 AM   #39
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Quote:
Originally Posted by Mindgame View Post
Shit, I wasn't aware you had to be a pro on the MT to purchase a BMW. Like I said, first manual car i've owned (not driven) and in some cases i'm thankful for that as it's a pretty forgiving car. Have had the car about a year now and haven't stalled it...well...for about a year now!

Anyways i'll leave you to better things - I would imagine a MT pro as yourself has multiple women to please on a pretty consistent basis
Thanks for proving the point.

Actually I'm not really talking about you. Just read over the thread again. Well I'm off to my chicks. I just work the pedals, they work the shifter.
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      11-11-2009, 03:09 AM   #40
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Originally Posted by BForbes View Post
Please, do tell. I can point to more embarrassing threads.
Please don't. Let us collectively hold on to what little dignity we have left

(fwiw, I'm fairly certain the comment you quoted wasn't directed at you)
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      11-11-2009, 07:26 AM   #41
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I would imagine a MT pro as yourself has multiple women to please on a pretty consistent basis

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      11-11-2009, 04:27 PM   #42
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Quote:
Originally Posted by John@BMW View Post
i rev match 100% of the time- its 2nd nature to me.
as do i. at first i did it out of habit, but mostly b/c i wanted to minimize both brake wear and clutch wear. now i do it b/c i have little choice, excluding the option of using my brake pedal. you see, i have what many would consider an insane clutch to have in a street car. nevertheless, i installed it first and foremost for track weekends, and also to be ready for when i go single and make lots of power. needless to say, it functions like an on/off switch - there is no in-between. there is no slipping or feathering this clutch, or the driveline (and thus the whole car) begins to shudder. as such, i have to make quick gear engagements. hence, in order to minimize the "jerky" feel of a downshift, i must rev-match.


Quote:
Originally Posted by ChrisV View Post
How long have you been driving? With modern synchros it's simply not necessary unless you are racing and downshifting. Street driving, there's simply no need to shift faster than the synchros can handle. The trans will still last forever and it's not jerky at all.
this is only partially correct. it is true that rev-matching is unnecessary with modern synchros b/c it will effectively prevent you from grinding gears. however it is not true that synchros will completely eliminate the "jerk" you'll typically feel when downshifting without rev-matching. the fact of the matter is that the synchros only cushion the blow. they make it possible to make "less-than-perfect" shifts - that is, they sync the drivetrain rpm and the engine rpm when they are not equal (for instance when someone downshifts without rev-matching, or when someone's rev-match is less than perfect). before synchros, this would have resulted in grinding gears - synchros prevent that to a certain extent...but they do not emilminate drivetrain "jerk."

if words are hard to follow, a physical experiment never fails: simply cruise at 40mph in 3rd gear and downshift to 2nd gear without rev-matching...even with a manual transmission with gear synchros, you are still going to feel a "jerk" as the clutch engages the flywheel, the drivetrain rpms drop, and the engine rpms rise to meet at some middle ground. there are only two ways to eliminate the "jerk" - 1) let out the clutch slowly (just like you would feather/slip the clutch into 1st gear from a stop)...and even then you're still going to feel the car's tendency to slow down, even though its gradual (as opposed to the sudden jerk you get when you pop the clutch out quickly), or 2) rev-match.



Quote:
Originally Posted by Mindgame View Post
For those of you that Rev match...this is only an attempt to rev match precisely correct? I'm assuming you don't know exactly what your RPM's are after downshifting at your current speed....only a rough estimation....?
in the beginning, for instance with a new or unfamiliar car, it is a guessing game. after a while, i would imagine some people figure out the rpms at their favorite shift points and commit them to memory. i don't do it this way - others (myself included) do it be feel...for instance, when i'm @ 40mph in 3rd and want to downshift into 2nd, i just "know" how much to blip the throttle and what engine pitch to listen for in order to "know" if i'm at the correct engine rpm. most of the time i'm within 100rpm or so. but occasionally i miss the downshift by a few hundred rpm, and i know it not only by the "jerk" i feel, but also by the abrupt change in engine pitch as i engage the gear.



Quote:
Originally Posted by NYCGarbagePrince View Post
Cause he is wrong. You are not going to need to replace your clutch because you downshift. You are going to need to replace your clutch for downshifting into 2nd from 5th. Not 2nd from 3rd. or 3rd from 4th. Doing burnouts, riding your clutch from gear to gear... resting your foot on the clutch while driving. These are the types of things that cause your clutch to fail. Not downshifting.

My fleet of trucks consist of mostly automatics and about 5 manuals. They all used to be manuals. I learned how to drive a truck on manual transmissions. I only use the clutch to go from neutral to 1st and from neutral to reverse. Otherwise, you hit your RPM target and lift from the gas and shift. It works with every manual transmission. My trucks go almost 100k without clutch replacement and my drivers are downshifting. If they weren't downshifting they would never be able to slow down the trucks with a full load, the brakes would simply overheat and explode.

If you want to combat that argument, ask him why he is driving a car with a clutch if he doesn't want to use it? 4 brake pads installed on a BMW are not cheap... at all.
i agree with you regarding the "pedal braking vs engine braking" issue. however, it is not true that downshifting won't wear your clutch. synchros may keep your gears from grinding (for the most part), but they won't rev-match for you, and therefore they won't make the clutch engage the flywheel at matching rpms. only YOU can ensure that this happens by rev-matching. the more often you downshift without rev-matching, the faster your clutch will wear from engaging the flywheel at mis-matched rpms (which is the same kind of wear caused by riding the clutch or slippin/feathering it alot). remember, transmission wear and clutch wear are two VERY different things.

also, downshifting from 5th to 2nd will not wear your clutch or hurt your engine provided 1) you're not going so fast in 5th gear that the downshift causes engine rpm's to skyrocket beyond the rev-limiter, and 2) you rev-match so that the clutch engages the flywheel at the same or similar rpm's. however, i cannot say the same for the transmission. in fact, i wouldn't be surprised to hear some gears grind despite having synchros, as they might struggle to make such a large change in rpms. but again, that's transmission wear, not clutch wear.



Quote:
Originally Posted by Citizen Z View Post
I prefer to use the brakes because like the clutch, the brakes are a wearing item, however they are a heck of a lot cheaper to replace, even accounting for longevity.
the point you and some others are missing is that with rev-matching, you are minimizing both wear on the brakes AND wear on the clutch. its downshifting without rev-matching that wears the clutch out.



...just some food for though everyone. i'm not trying to call anyone out...just trying to correct some misinformation.
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      11-11-2009, 04:39 PM   #43
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It's not that hard to do heel toe braking, just feels much smoother to me when I do. Now if people are double clutching every down shift on a modern car, yeah that's a bit excessive, but I don't find proper rev matching on a downshift excessive.
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      11-11-2009, 05:06 PM   #44
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when I'm on 4th cruising ~40-45mph and coming to a stop, I rev match down shift to 2nd
if I'm on 3rd, I just let the rev drops to about 1000rpm and just go to netural and brake
if I'm on 4th at speed, need to slow down for an freeway exit, I heel toe double clutch to 2nd. I just find it smoother to double clutch to 2nd coming from like 80mph on 4th. or if I feel like it, I heel toe no double clutch to 3rd then to 2nd. i.e. I generally double clutch when I skip gears.
if I'm on 3rd on streets and needs to make a 90degree turn, I heel toe to 2nd.

rev-matching from 6th to 5th is not necessary in this car... they're like a few hundred rpm different at around 80mph.. besides... why go from 6th to 5th? What's 5th gear for apart from dyno?
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