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Synchros shot? Weird noises while shifting? Not sure what needs to be replaced?
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Terms, definitions, and common acronymns found here!

Post by Johnf514 »

Friction Point - The point during the clutch pedal travel where the clutch first begins to touch the flywheel. From this point on until the clutch is fully engaged, it is slipping and applying continually more pressure against the flywheel to get hooked up.

Clutch Slip - Any time the clutch is not fully engaged or disengaged when the car is running, it is slipping against the flywheel. As the clutch comes up and reaches the friction point it begins touching the flywheel, and they are spinning at different speeds. They must sync up and during this time the clutch is slipping. When it is slipping it is wearing. The clutch is designed for this purpose and it is designed to wear. But excessive and unnecessary slipping will reduce clutch life.

Upshift - Shifting up through the gears: 1 -> 2

Downshift - Shifting down through the gears: 4 -> 3

Throw - The distance the shifter moves between gears.

Engine Braking - When in gear and off the throttle the compression of the engine creates drag against the drivetrain and the wheels, slowing the car down. Lower gears provide stronger engine braking than higher gears.

Coasting
In Neutral: Rolling down the road with the car in neutral. This is generally an unsafe maneuver as you do not have total control over your car, because you can not immediately accelerate. In many places it is illegal. Coasting in neutral uses the same amount of gas as idling, as the engine must maintain idle speed to keep running in neutral.
In Gear: Rolling down the road with the car in gear but off the throttle. This will produce some engine braking. The engine is forced to run at it's given revs due to its direct connection to the rolling wheels. In modern fuel injected cars, coasting in gear above around 1500k rpm (different in different cars) uses no gas, as gas is not needed to run the engine due to the wheels driving it.

Lugging - When your speed is too low for the gear you are in and your engine is lugging or laboring to produce power, accompanied by an unpleasant sound and a shaking or shuddering of the car. This is not good for the engine or fuel economy.

Blip - Tapping the throttle during a downshift to rev-match.

Straight Cut - Many cars have straight cut teeth on reverse gear. This makes it harder to engage and produces a whining sound when traveling in reverse. This is normal. If you have trouble shifting into reverse, try first shifting into a forward gear, and then into reverse.

Synchros (Synchromesh) - These are cone shaped devices within the gearbox that sync up the speeds of the input and output shaft so the gear can engage. You can save wear on these if you double clutch but it is not really necessary in modern cars, the synchros are designed well and last a long time. If they do wear out you can work around it by double clutching.

Rev-match - Matching the engine/flywheel speed to the speed of the clutch, to reduce clutch slippage and have smoother shifts. Wait for the revs to drop when up shifting (or shift fast to get it done before they drop too far, I have this problem some times in my 6 speed). For downshifts blip the throttle to raise the rpms for the lower gear.

Single Clutch - General way of shifting modern cars with synchromesh gears. Clutch in, shift from one gear to another through neutral, clutch up.

Double Clutch - Bringing the clutch up in neutral during a shift. Double clutching is not really necessary in modern synchromesh cars but it can make things smoother and is fun. You are basically not only rev-matching the engine to the clutch, but also the input shaft to the output shaft between gears, doing the job of the synchros. For a double clutch downshift: clutch in, shift gear to neutral, clutch out, blip throttle (this is the rev-match for the input shaft to the output shaft), clutch in, shift neutral to lower gear, clutch up. If you do it fast enough the one blip in neutral is enough. If the revs fall too fast you can give a smaller 2nd blip before clutching up. Cars without synchromesh gearboxes require this maneuver. Double clutching is also useful for downshifting into 1st as many cars do not have synchros or have weak synchros on 1st gear.

Heel Toe - Braking and rev-match downshifting at the same time. Brake with part of the right foot, clutch with left foot, shift, blip throttle with right part of right foot while continuing to brake with left part of right foot, clutch up.

Bump Start - Starting the engine using the clutch and the momentum of the car. Get the car rolling, and put it in gear, 2nd is probably best, with the clutch down while the car is rolling, quickly release the clutch. This will spin the engine up. As soon as the engine is running clutch back in to avoid stalling/bucking/jerking/zooming off the road, etc. This is not a generally recommended technique but is useful if you must start your car and the starter is not working. Also, some people swear by this method for fuel economy via turning off the engine and coasting, and then bump starting when acceleration is needed.

Stall - We all know what this is. It sucks. It happens to everyone. It can be embarrassing. But it's not hurting your car so don't worry about it.

Bucking Bronco - When starting out from a stop in first you either released the clutch too fast, or gave too much gas, or both, and the car jerks and jolts, like riding a bucking bronco. It's painful and embarrasing but it happens to everybody.

Grinding - When you mess up a shift and hear grinding, it is not the actual gears in the transmission. It is actually the synchros. It's a bad thing and you want to try to avoid it, but doing it a few times every once in a while is not going to destry your car.

Power Shifting - Shifting with the throttle floored the whole time. You have to shift very quickly and this isn't recommended unless you really know what you're doing.

Clutchless Shifting - Just as it sounds, shifting without the clutch. You have to do it at the exact right revs and know what you are doing or it will grind and you have the potential of really messing things up. Not recommended.

Short Shifting - Shifting at low rpms to save fuel, as opposed to shifting at high rpms to maximize acceleration and power.

Rev Limiter - Cuts fuel to prevent going over red line when revving the engine with the throttle.

Over Rev
Throttle induced: Revving the engine past the redline using the gas pedal. You will bounce off the rev-limiter.
Mechanical: The engine is forced over the redline via being in far too low a gear for the current speed. The direct connection between the wheels and the engine forces the engine to spin too fast. The rev limiter can not help here and things can start getting very damaged very fast.

Power Band - The rpm range where your car produces the most power and has the best acceleration. If you want to have fun, keep it in this range ;)

(Note: this thread was taken from a post by jomotopia. Thank you, jomo, for your lengthy contribution. It will be a sticky for all time. :D )

Please feel free to add to this thread, as we're always coming up with new words and terms.
Last edited by Johnf514 on Thu Jun 15, 2006 12:46 pm, edited 2 times in total.
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Post by jomotopia »

No Gas Start - Using only the clutch with no thorttle input to get the car moving. Let the clutch out very slowly and you will feel it start to grab at the friction point. Continue to let it out slowly and the car should start moving forward slowly. If your car is really lacking for torque you may need to give a tiny amount of gas. This is a good thing to practice for a while in a flat empty parking lot when you first get your car, so that you can get a good feel for the friction point.
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Post by jomotopia »

Skip Shift / Block Change - Changing gears non-sequentially. For example 3 -> 5 or 4 -> 2.
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Post by Johnf514 »

Proper thought process of clutch wear:
jomotopia wrote:longer slips [of the clutch] and higher rpms produce more clutch wear.
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Post by jomotopia »

Popping / Dumping the Clutch
six wrote:Popping the clutch is even worse than dumping it. When you dump the clutch, you release the clutch really fast. When you pop it, you basically slide your foot off of the clutch and allow it to spring up by itself.
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FAQ 2.0! <- New Members Read First

Post by Johnf514 »

Note: Terms, definitions, and confusing words found here!

This thread is for suggestions and entries on all topics "stick" to help create the FAQ 2.0. If you're reading/searching and happen to see something that's well written and defines a subject (i.e., rev-matching, double-clutching, etc.), please post it here. Please include the original author's name. I'll be taking the posts and formatting them into an FAQ with the original author's name and the "assist" person, or the person who found it.

For those looking to use the thread as an FAQ, feel free to use CTRL-F on your browser to "find" the term you're looking for. Or, just skim!

Also, please attempt to find the most accurate posts possible. If you edit the post, please underline what you've edited.

This is kind of like a scavenger hunt, so find as many quality posts on as many standardshift-related topics as you can! Use our search feature to narrow your quest. There will be a prize for the person with the most submissions! :D
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Downshifting

Post by Johnf514 »

Downshifting

Author - jomotopia
Submitted by - jomotopia and papercliprebel


There are a few reasons to downshift:

1> you need to accelerate quickly, usually for passing
2> you are going to slow down but not stop, and then reaccelerate, usually for a turn, or changing traffic speed
3> you are going down a long decline, you can put it in a lower gear to have engine braking maintain speed without riding and burning up your brakes.

4>with the purpose of clutching out in neutral would be to rev the engine AND synchros while the remainder of the drivetrain maintains the road speed. the way you described it (which is also acceptable) doesn't match the synchos speed to the engine - for that you absolutely have to clutch out when rev matching. also, your steps describe only a single clutch step contrary to the name of the move "double clutch"

there are many different ways of doing just about anything in a manual, and this is especially true of downshifting. it's largely a matter of preference and driver style. here's how I do each of these:

1> say i'm crusing in 5th at around 2000 rpm. (i think more in rpms than speed, since i um... really don't care about the speed limit Wink) now my car has good power but it's real power band is higher than that, i gotta get the turbo spooled. i need to go to 4th to get some acceleration and pass somebody. so i do a double clutch downshift:

1.off gas
2.clutch in
3.neutral
4.clutch out *****
5.blip throttle
6.clutch in *****
7.lower gear
8.gas

now of course that's written as a list but as it's been pointed out (by Prodigal Son i believe?), you can't really think if it like a list of steps of what to do. each one flows into the next and it's a very quick, smooth action.

2> turning. i'm coming up to a turn in 5th. i do the same double clutch downshift as before except i leave out step #6. after that i start braking for the turn in 4th. then i heel-toe double clutch to 3rd, and then 2nd if needed. i generally prefer to go through all the gears sequentially but that's not necessary. i think it's more fun though Wink HTDC is braking with the left part of my right foot and doing the same double clutch steps above, except that when blipping the throttle i am using the right part of my right foot while still applying steady brake pressure. once in the desired gear (3 or 2 depending on the speed of the turn) i finish braking to the proper speed, release brakes, and then turn.

3> approaching downhill in 5th. at the top of the hill i do a double clutch downshift to 4th but no gas at the end b/c i'm not trying to accelerate. then go down the hill in 4th with no gas or brake (unless traffic requires of course) and the speed is pretty steady (depending on grade).
Last edited by Johnf514 on Fri Jan 12, 2007 3:43 pm, edited 2 times in total.
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Post by jomotopia »

Hand Brake Method
For starting on inclines

Author - JackBauer
Submitted by - jomotopia

1) the hand brake method- Verrry simple.
-You put the hand brake all the way up.
-let go the foot brake
-disengage clutch (push it in)
-rev engine- like you usually would before taking off
-let the clutch out till it gets to the catch point- at this point you will feel the car want to move
-keep the clutch at the friction point when the car wants to move
-let the hand brake all the way down
-add a little or ease off gas- depending on how high the rpms are ( you know- just like you would when starting not from an incline) & let off the catch point.
- your moving! and you didn't move backwards a single millimeter

Alternative to hand brake:

2) -right foot on brake- left foot on clutch
- let out clutch to catch point
-quickly move right foot from brake to accelerator & keep a constant rev
-get off the clutch - let it slip real quick
-add gas
- voila

bogus83 wrote:Stomping the gas on an uphill start really doesn't help. You might be revving higher, so when the clutch actually engages you'll take off faster. But until the clutch bites you're rolling backwards, .5k RPMS or 5k RPMs.
Last edited by jomotopia on Wed Jan 17, 2007 10:18 am, edited 1 time in total.
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Post by jomotopia »

Engine Braking - Active vs. Passive
Prodigal Son wrote:Ah yes, one of the problems in discussing this topic it that we use the words "engine braking" in two different sense. There is the phenomenon of engine breaking that happens in any car (AT or MT) as soon as you let off the gas. It the engine is not driving the wheels, the wheels are driving the engine, and that slows the car down. You get that kind of engine braking just by letting off the gas. (Sometime, if you put the clutch in, it almost feels as if the car accelerates as the engine breaking is removed.) Lets call this passive engine braking.

Then there is active engine breaking where you deliberately shift into a gear that is too low for the current speed to take advantage of the engine breaking effect. Let's call that active engine breaking.
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Post by Hatchman »

The no-gas downshift

Let off the gas. Depress the brake, without disengaging the clutch, until speed drops a little above the minimal speed for the current gear. Disengage the clutch. Shift to the lower gear. Release the clutch smoothly with a slight pause at the friction point. If after engaging the clutch we obtain the required lower speed, we release the brake. Otherwise, we contiinue braking to obtain the required speed.
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Post by Hatchman »

If you are in 3rd or 4th gear and you brake to 1500/1000 rpm in one of those gears, you clutch in, shift to 2nd, and clutch out, sometimes continuing to brake, sometimes not. No gas is used during the shift sequence. At the moment you clutch in (this is why I put it in bold), and you are effectively braking in neutral, your revs continue to drop, down to idle actually, and then "below idle" for the gear you were in before the sequence (3rd or 4th). The clutch in and clutch out is brief, so it's not as if you're rolling very far in neutral. So I see "below idle for the higher gear" putting you in ideal rev-range for the lower gear (2nd). I think "below idle" is a hypothetical concept, not a practical one (obviously).
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Post by jomotopia »

Speed Bumps / Humps

Author - jomotopia, Sypher, various
Submitted by - jomotopia

For a speed bump:
1. approach in 2nd
2. brake to very slow speed
3. clutch in
4. coast the front wheels over
5. now if i am still over 5mph i will slip the clutch in 2nd to creep the back wheels over
5b. if i was under 5mph i will drop it into 1st and do a "slow start" to pull the back wheels over

for a speed hump, you can probably creep over it with a little bit of gas in 2nd without ever clutching in.
Sypher wrote:So what I do is for bump (taken at much slower speeds than humps), I would slow down to almost a stop, shift into gear 1, and ease over it. For humps, I generally take them in gear 2 at different speeds depending on the size of the hump.
Also many people just approach the bump/hump, clutch in, and coast over it. Then grab 2nd or 1st depending on speed and go.
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Post by jomotopia »

Why is my 1-2 shift so jerky?

Author - jomotopia
Submitted by - jomotopia

The 1-2 shift is the most difficult to get smooth. This is because the change in gear ratio is the greatest of all the gears, and because lower gears provide more force on the wheels.

The way you jerk on the shift will tell you whether your revs were too high, or too low. If the car surges forward when you let out the clutch, pushing you back in your seat, the revs were too high. If the car jerks back, sending you forward in your seat, the revs were too low.

If your problem is the revs falling too low, often the case on performance cars where the revs fall fast, and on 6 speeds where the gears are closer together, you can try the following:

1. Shift faster. Try to get the car into 2nd gear and the clutch out quickly before the revs drop too much.

2. Add a bit of gas when bringing up the clutch. You don't want to make the revs go up, just a little gas to keep them from falling as fast, so they won't have fallen as far by the time you let out the clutch.

3. Don't take your foot fully off the gas when shifting from 1 to 2, in a manner to produce the same effect as number 2.

4. Run first up a little higher. The higher you are in the revs when you upshift, the farther they will have to fall for the next gear. This is because the difference between gears is not a direct RPM number, but a multiplier.

If the problem is that the revs do not fall far enough before you let out the clutch, you can try the following:

1. Simply wait for the RPM to drop to where it should be for 2nd gear before releasing the clutch.

2. Shift at a lower RPM for the same reason (and opposite effect) as #4 above.
Last edited by jomotopia on Fri May 25, 2007 4:37 pm, edited 1 time in total.
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Post by jomotopia »

Why is it so jerky when I let off the gas in lower gears?

Author - jomotopia
Submitted by - jomotopia


This is perfectly normal. Because of the short gear ratios and direct connection between the wheels and engine, any modulation of gas is felt through the car. It is very important in a manual to be smooth and gentle on the throttle. If you are crusing in 2nd and dump the gas, you will feel a lot of jerkiness. Ease off the gas to smooth it out. When slowing down in a low gear, not taking your foot completely off the gas can help keep it smooth as well. The whole key is throttle manipulation and modulation. If you are coming from years of driving an automatic, this will be difficult and you will basically have to "reprogram" your right foot to be smooth and gentle.
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Post by jomotopia »

Is it better to over rev or under rev a rev-match downshift?

Authors - Prodigal Son, jomotopia, eaglecatcher, thepsyche35, grievre, Sypher
Submitted by - jomotopia

Prodigal Son wrote:I'm trying to work something out in my head, so I though I would put it out there for the combined brain power of the standardshifters to comment on.

It seems to me, based on both logic and experience, that it is better to over-rev a rev match than to under-rev one.

Experience says that when I have over-revved one, a slight slow-down on the engagement is enough to smooth it out, whereas if I under-rev it, there is always a tug that gets transferred to the car.

Logic suggests to me the the engine, without gas, is trying to slow down, so the clutch can more easily slow it done by 500 RPM than speed it up by 500 RPM. In addition to that, the resistance that the engine provides in engine braking (usually attributed to compression, though I have seen that disputed) is acting to prevent the engine from speeding up, and is either neutral or assertive in helping it slow down.

The reason for my thinking along this line is that if it is correct, and given that exact rev matching is really hard to do, it would make sense to aim to slightly over-rev ones rev matches so that one almost always errs on the side of too high. I suspect that it what I do now -- just as a matter of naturally adapting my behavior based on what works. But with all this talk about technique, I'm now interested to work out if this is a valid principle that is worth passing on.
jomotopia wrote:i also think you are correct about aiming a little high for the rev match. not only because of the reasons you stated, but also to give the driver a little time to catch the right revs as they're coming back down.
eaglecatcher wrote:I think your're right too. It's easier to slow the engine down, which you really won't feel, than to abruptly slow the wheels down, slowing the entire car, and its contents.
thepsyche35 wrote:I think it was IMboring who once posted that it would wear less on the clutch/drivetrain as a whole if you over-rev it because with an over-rev, the parts will be going with friction to slow the engine down, whereas under-rev will cause you to go against friction to make up the RPM difference, which one would think causes more wear.
grievre wrote:It's better to aim high, as when your foot is off the gas the engine is slowing down, and it's better for the clutch to be pushing the engine in the direction it already wants to go.
Sypher wrote:Over reving is better than under revving. It is easier for the clutch to slow the engine down becuase the engine originally wants to slow down whne no gas is fed to it.
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