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The 2010 MZ3 is my first car with a manual transmission. I'm trying to learn as much as I can so I dont kill the poor car. I've been shifting at around 3,000 RPM for every gear and I was just wondering what everyone else does. Also, when I am cruising on the highway at around 75-80mph, I'm in 6th gear at about 3,400 RPM. This seemed a little bit high to me-- is it?

Thanks
 

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Well, shifting points depend on what you are doing and what gear you're in.
For instance, if I am just moving in traffic and not looking at accelerating very quickly (I am assuming you're on a 2.5 L engine) I will go through the first 3/4 gears without getting past 2K or 2.1/2.2K. If I am moving at a quicker pace, I'll be shifting around 3K/4K. If I am on a fast spree, I'll be switching between 5 and redline.

75mph should be 120 kms/hr. I can't bet my house on it, but I believe that at that speed your rpms should be a whisk over 3k. Precisely, I believe 3.1.
As far as it being a little too high, let's do some math: if you do 75 mph (120Kms/hr) at 3.1K rpms, you'll be doing 150 mph (240 Kms/hr) close to redline.
As far as my experience goes, it is just about right. For you to cruise below 3k rpms in 6th, your 6th gear would have to be good for at least 160 something mph, up to 170 (260 kms/hr or more). That would be a ridiculously high top speed for a car this size and performance.
My RX7 should be good for a top speed of at least 275 kms/hr (172 mph) and it is considered a high performance sports car (0-60 5 seconds flat in stock configuration and 1G cornering ability on 225 tires)

Please note: when we talk about top speeds here, we are talking strictly theoretically. What this means is that if your engine can spin 6K and you're doing 120 at 3K, then your top speed is 240.
Real top speed in top gear depends on many other factors. As most of us already know, there is a speed governor that won't let you drive past 180 (or something like that). Also, even without it, your engine might not produce the horse power necessary to push your car to redline in its highest gear. This is actually something pretty common in large production cars, as they tend to put a fairly long 5th/6th gear in the car to allow the engine to drive on a highway at reasonable speeds keeping the rpms relatively down. Typically, it'll be the drag that will keep your car from topping off in top gear.
Just to give you an example, I used to have a 97 Neon. The car was somewhat modified (not that much, really) and I hit 215 kms/hr in 5th. I still had another 1000 rpms or so to go. I knew already at that time however, that I wouldn't have been able to hit redline as the drag limited that car's speed to about 220 Kms/hr.

I hope this helps.
 

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Well, shifting points depend on what you are doing and what gear you're in.
For instance, if I am just moving in traffic and not looking at accelerating very quickly (I am assuming you're on a 2.5 L engine) I will go through the first 3/4 gears without getting past 2K or 2.1/2.2K. If I am moving
good post!
 

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i'm almost always 2500-3k. that seems to allow for the smoothest transition for me to the next gear without slipping out the clutch. that being said, i milk the HELL out of the coasting of this car. i'm in neutral a good amount of the time just letting it cost to a stop, down a street, etc. engine breaks are nifty, but coasting for a 1/2 mile in traffic (for example, off an exit ramp) makes like pretty easy.
 

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i'm almost always 2500-3k. that seems to allow for the smoothest transition for me to the next gear without slipping out the clutch. that being said, i milk the HELL out of the coasting of this car. i'm in neutral a good amount of the time just letting it cost to a stop, down a street, etc. engine breaks are nifty, but coasting for a 1/2 mile in traffic (for example, off an exit ramp) makes like pretty easy.
+1 on that coasting business.
Mee toooo!
(and -of course- I forgot)
 

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Well, shifting points depend on what you are doing and what gear you're in.
For instance, if I am just moving in traffic and not looking at accelerating very quickly (I am assuming you're on a 2.5 L engine) I will go through the first 3/4 gears without getting past 2K or 2.1/2.2K. If I am moving at a quicker pace, I'll be shifting around 3K/4K. If I am on a fast spree, I'll be switching between 5 and redline.

75mph should be 120 kms/hr. I can't bet my house on it, but I believe that at that speed your rpms should be a whisk over 3k. Precisely, I believe 3.1.
As far as it being a little too high, let's do some math: if you do 75 mph (120Kms/hr) at 3.1K rpms, you'll be doing 150 mph (240 Kms/hr) close to redline.
As far as my experience goes, it is just about right. For you to cruise below 3k rpms in 6th, your 6th gear would have to be good for at least 160 something mph, up to 170 (260 kms/hr or more). That would be a ridiculously high top speed for a car this size and performance.
My RX7 should be good for a top speed of at least 275 kms/hr (172 mph) and it is considered a high performance sports car (0-60 5 seconds flat in stock configuration and 1G cornering ability on 225 tires)

Please note: when we talk about top speeds here, we are talking strictly theoretically. What this means is that if your engine can spin 6K and you're doing 120 at 3K, then your top speed is 240.
Real top speed in top gear depends on many other factors. As most of us already know, there is a speed governor that won't let you drive past 180 (or something like that). Also, even without it, your engine might not produce the horse power necessary to push your car to redline in its highest gear. This is actually something pretty common in large production cars, as they tend to put a fairly long 5th/6th gear in the car to allow the engine to drive on a highway at reasonable speeds keeping the rpms relatively down. Typically, it'll be the drag that will keep your car from topping off in top gear.
Just to give you an example, I used to have a 97 Neon. The car was somewhat modified (not that much, really) and I hit 215 kms/hr in 5th. I still had another 1000 rpms or so to go. I knew already at that time however, that I wouldn't have been able to hit redline as the drag limited that car's speed to about 220 Kms/hr.

I hope this helps.
srsly /thread

there's really not a lot anyone can add on to that. lol
 

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Discussion Starter #7
Thanks for the info guys! I appreciate the in depth explanation. It sounds like I am doing what I should be for the kind of driving I do, which is mostly highway that has traffic lights on it. When I shift from 1 to 2 and from 2 to 3, often times its a little bit rough. I'm thinking that its because I"m not staying on the clutch long enough during acceleration? I know theres probably no way for you to know without witnessing it, but I admit that I am a noob when it comes to driving stick, so I'll take all the pointers that are given to me.
 

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If your getting some jerkiness there are two possible symptoms that I can think of.

1) Like you said, your coming off the clutch too fast

2) You are shifting waaaaayyyy to slow and your speed is dropping enough to cause a jerk as you put it in gear and the RPMs catch up to the actual speed of the car under load.

Most likely it's #1.

Keep at it and you'll be surprised at how quickly you pick it up. After a few months, it will become second nature...as if the car is an extension of your hand. That is when the fun begins!
 

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Shifting at 3000 puts you squarely at about halfway through the powerband and roughly at about 90% of the torque capability of the vehicle. So you're making 83 out of a possible 156hp at 3000rpm. Peak hp is at ~5500rpm on these cars and carries on until about 6300 fairly flat in that area. I put up a graph of the horsepower and torque of the vehicle across the full range of rpm so you can see what kind of abilities the car has torque wise (that's really what is going to make the difference for smoothe shifts, bogging, and stalling. As long as you've got a 2.5, you should be fine all day long for torque (which I know you do because you have a six speed).

And Desertnate, I don't know about you, but my car is certainly not an extension of my hand. It's an extension of my FOOT! :yes: :w00t 1:

Jason
 

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Discussion Starter #10
Thanks again for the wealth of info-- and nice graph, Jason.

If your getting some jerkiness there are two possible symptoms that I can think of.

1) Like you said, your coming off the clutch too fast
At what point, however, are you on the clutch too long and burning it?
 

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when you shift, it should be foot on clutch, shift, foot off clutch...shouldn't take more than 1/2-1 second or so. don't ride it out like you would a brake pedal. but if you shift then pull your foot off and let it just slam out your car will get jumpy. that's also not super great on it.
 

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Discussion Starter #12
when you shift, it should be foot on clutch, shift, foot off clutch...shouldn't take more than 1/2-1 second or so. don't ride it out like you would a brake pedal. but if you shift then pull your foot off and let it just slam out your car will get jumpy. that's also not super great on it.
So what you're saying is to basically let the spring tension in clutch do its thing, but keep your foot on it to provide a small amount of resistance?
 

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i've noticed that the rpms, on a normal shift, no matter really what gear, should not drop more than 300-500 rpms. if they are dropping more than that during your shift, you're shifting too slow. that's the gauge. if they drop less than that, you either have a smooth shift or you shifted at the right rpm.

i hope that makes sense.
 

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Discussion Starter #14
Yes that does make sense. I dont think that I am shifting too slow, but now that I have some numbers I should be able to take a better look at it. I think most of the roughness is probably due to clutch/accelerator balance.
 

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Well, shifting points depend on what you are doing and what gear you're in.
For instance, if I am just moving in traffic and not looking at accelerating very quickly (I am assuming you're on a 2.5 L engine) I will go through the first 3/4 gears without getting past 2K or 2.1/2.2K. If I am moving at a quicker pace, I'll be shifting around 3K/4K. If I am on a fast spree, I'll be switching between 5 and redline.

75mph should be 120 kms/hr. I can't bet my house on it, but I believe that at that speed your rpms should be a whisk over 3k. Precisely, I believe 3.1.
As far as it being a little too high, let's do some math: if you do 75 mph (120Kms/hr) at 3.1K rpms, you'll be doing 150 mph (240 Kms/hr) close to redline.
As far as my experience goes, it is just about right. For you to cruise below 3k rpms in 6th, your 6th gear would have to be good for at least 160 something mph, up to 170 (260 kms/hr or more). That would be a ridiculously high top speed for a car this size and performance.
My RX7 should be good for a top speed of at least 275 kms/hr (172 mph) and it is considered a high performance sports car (0-60 5 seconds flat in stock configuration and 1G cornering ability on 225 tires)

Please note: when we talk about top speeds here, we are talking strictly theoretically. What this means is that if your engine can spin 6K and you're doing 120 at 3K, then your top speed is 240.
Real top speed in top gear depends on many other factors. As most of us already know, there is a speed governor that won't let you drive past 180 (or something like that). Also, even without it, your engine might not produce the horse power necessary to push your car to redline in its highest gear. This is actually something pretty common in large production cars, as they tend to put a fairly long 5th/6th gear in the car to allow the engine to drive on a highway at reasonable speeds keeping the rpms relatively down. Typically, it'll be the drag that will keep your car from topping off in top gear.
Just to give you an example, I used to have a 97 Neon. The car was somewhat modified (not that much, really) and I hit 215 kms/hr in 5th. I still had another 1000 rpms or so to go. I knew already at that time however, that I wouldn't have been able to hit redline as the drag limited that car's speed to about 220 Kms/hr.

I hope this helps.
Very nice man :clap:
 

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A couple of things

I would like to correct the "potential top speed of my RX7. I drove it today and -after a second evaluation- it should be good for close to 300 Kms/hr at redline (that is, remember, strictly theoretically speaking).

Second, I would like to point out one thing: when you shift from one gear to another, the drop in rpms depends first and foremost on the gearing and not on how quickly you shift.

If you were able to shift from one gear to another in no time whatsoever (like a Ferrari Enzo almost does), then the drop in rpms would be strictly gearing dependant.
Since you always take some time to go from one gear to another, while your car is in neutral and you're off the gas, it'll slow down somewhat between shifts, so at the moment the clutch re-engages, the rpms will climb to a level that is a bit lower than what it would be if you shifted in no time whatsoever.

Since the average driver doesn't spend a lot of time between gears, if your rpms are dropping way too much, you are taking 3/6 seconds to go from one gear to the next. If that's the case, you need to keep exercising your timing and your speed. Please make sure you always hit the floor of the car with the clutch when shifting and use that as your cue to move out of and into a gear.

One last thing: the gearing in the car can be quite different between 1st and second if compared to 5th and 6th. You cannot expect the same drop. At often times, manufacturers will choose gear ratios based on advertising plans.
Theoretically speaking, once you have set your lowest and highest gears (based on what the car can do), the other 3 or 4 should be equally spaced in between. Manufacturers however, often will gear a car so that you can hit 60 mph (or 100 Kms/hr) with a certain time, so they can advertise that their car is quicker than a competitor. This might consequently carry an uneven spacing of gear ratios (often between 2nd and 3rd in a 5-speed transmission). Similar consideration applies to the gearing of the tallest gear (6th in our case); its length will be strongly influenced by the rpms levels the manufacturer considers appropriate at cruising speeds, mpg, and all that.
I'll go back to my good ol' neon. While you could hit 60 mph in second, you were in for a (sad) surprise when you'd shift to third, as the drop in rpms was considerably higher than it was between 1st and 2nd or 3rd and 4th (IIRC, about 500 rpms from 1st to 2nd and 800 from 2nd to 3rd). As well the 5th gear, like stated before, was tall enough to allow (theoretically) mind-boggling speeds for that type of car. At the end of the day, Chrysler had spaced them this way: 1-2 short, 2-3 long, 3-4 short, 4-5 long.

I would agree with what some have suggested, which is that you are dropping off the clutch too abruptly if the car jerks a lot even in relatively higher gears. Just try to do everything at a reasonably slow speed, then build up on what you see works well.

Sorry for another biblical post.
 

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Sorry for another biblical post?

Are you kidding me, I don't think it's possible to be more thorough and informative than you have been. Thanks again for all of the in-depth info.

My main concern right now is just getting my timing down. I feel like I'm so slow off the line and its kind of frustrating.

And hill starts.....
 

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hill starts suck. especially if someone pulls up on your ass and you have little room for error. if that's the case many times i just play with the clutch to stay put. it's not really good on the cluth to do this...but if necessary it is done. it's too hard to jump from break to gas, releasing the clutch some so you don't roll into the idiot behind you and not kill it all at the same time.
 

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for hill starts, just use your parking brake. hold it up, release the clutch til the gear catches (but keep your foot on it), put the parking brake down, and follow normal 1st gear starts. saves your clutch a little. i do this when i don't feel like matching revs and catch point exactly (which is usually all the time :tongue:)

swar19ren, practice getting the feel of where the catch point is if you feel slow to start. then practice revving to exactly 1300 and hold it there. once you get both down, combine the two, and voila, you'll be starting off fine.
 

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for hill starts, just use your parking brake. hold it up, release the clutch til the gear catches (but keep your foot on it), put the parking brake down, and follow normal 1st gear starts. saves your clutch a little. i do this when i don't feel like matching revs and catch point exactly (which is usually all the time :tongue:)
+1 for what he says.

Your "next step in hill starts would be to have 1/2 of your foot on the break pedal and use the other 1/2 to accelerate the car. I alternate between this and what haku said.

Clutch grabbing point can be a bitch. When I go from the 3 to the Jetta I always mess up. I don't stall it, but still mess up. Easier transition to/from the RX7, but I really don't know why (probably it is because it is almost impossible to stall...)
 
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