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Discussion Starter #1
School just started on Wednesday and I had a little problem. My MZ3 is the first stick car I've used for a daily driver, which I've had for about a month so I'm still perfecting my technique. Here's the problem. The school parking garage has a steep spiral ramp that I need to go up 4 floors. Normally, I downshift to second gear and cruise up the ramp at a slightly spirited speed. On Thursday though, there was a person in front of me who obviously didn't know the garage so they were going pretty slow and looking at the sign on each floor to see if they could park there. Being in second on such a steep climb at low speed, my car started to bog drastically; just on the verge of starting to stutter.

So here's my question: Does 1st gear have a syncro? I ask because I remember my friend's WRX, which I drove to learn on, didn't have a syncro so I couldn't go into 1st unless at a complete stop. Would it be ok to rev match into first? I'm assuming I'd have to rev it up pretty high to match the 15-20mph speed I enter the garage at. Should I double clutch (which I have yet to practice)? Can someone walk me through the exact steps on how to get to first? Thanks in advance :D
 

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If you're going 15-20 miles per hour then the car shouldn't be bogging in second. If you're only going that fast when you're entering and then slowing down then I'd wait until you're at the point that second is almost bogging down, then downshift with rev matching. At this point you should only be going 5-10 mph, so the rev matching shouldn't be that hard at all.

I imagine 1st has a synchro because I know it's possible to shift into first while still moving. Just practice and you'll probably be fine.
 

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double cone synchros on 1 & 2 single cone on 3 4 5
 

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You go to SJSU don't you? That sounds like the 10th street garage :eek: My 3 doesn't have that problem in that garage because it's an auto, but when I went there in my miata I had to rev match into 1st in order to make it up at a slow speed. Like icspots said, when you're in 2nd and you fell the engine bogging at low RPM rev it a bit and switch to 1st. You have to switch to 1st almost immediately after revving or it won't be as effective.
 

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Discussion Starter #5
Yup, SJSU 10th street garage. I was trying it out on the street today and for some reason I couldn't get the shifter in, even with rev matching. Am I not reving high enough? Am I supposed to jam it in there? I'm kind of scared to try it at school while uphill or else I'll start rolling back.
 

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[quote author=cpham53 link=topic=67972.msg1171163#msg1171163 date=1169864657]
Being in second on such a steep climb at low speed, my car started to bog drastically; just on the verge of starting to stutter.

[/quote]

would this damage the transmission or anything?? I ask because this happened to me too. I was in second gear on a steep climb at low speed with my car bogging drastically.
 

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[quote author=cpham53 link=topic=67972.msg1172173#msg1172173 date=1169945427]
Yup, SJSU 10th street garage. I was trying it out on the street today and for some reason I couldn't get the shifter in, even with rev matching. Am I not reving high enough? Am I supposed to jam it in there? I'm kind of scared to try it at school while uphill or else I'll start rolling back.
[/quote]

Rev matching will do nothing to help you get into first, double clutching, however, would help. When you rev match, you are increasing the engine speed, but what you need is to increase the transmission input/counter shaft speed to what it should be when in first gear.
 

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yup you need to double clutch to get into 1st easily at speed
 

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First gear has a shift interlock on it. It will not allow you to engage the gear if the speed differential between the 1st gear and the output shaft and the input shaft are beyond a certain amount (I am 99% sure on this, a lot of cars have this). What this basically means is that you will not be able to shift into first gear going more then about 5mph unless you double clutch to engage 1st gear. Driving at any speed or shifting at any speed into 1st is not a problem so long as you double clutch to engage the gear. Attempting to force it into gear strains the shift cables and can damage the synchros and shift interlock if you try to force it going more then about 5mph (if it won't shift in fairly easily then don't try it).


Proper double clutching procedure is as follows.
1) clutch in, shifter neutral
2) clutch out, rev match to about 500rpms above expected engine RPM in gear
3) clutch in, shifter in gear desired (1st in the case above)
4) either clutch out and you are in your gear, or since revs have likely dropped since you engaged the gear a slight gas blip to keep the revs close to matched and clutch out then.
-Matt
 

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[quote author=azazel1024 link=topic=67972.msg1174641#msg1174641 date=1170094344]
First gear has a shift interlock on it. It will not allow you to engage the gear if the speed differential between the 1st gear and the output shaft and the input shaft are beyond a certain amount (I am 99% sure on this, a lot of cars have this). What this basically means is that you will not be able to shift into first gear going more then about 5mph unless you double clutch to engage 1st gear. [/quote]

Nope, you can get into first gear at whetever speed you want. Not destroying your transmission once you release the clutch pedal is the problem here. But to get in first gear all you have to do is push the clutch all the way in, raise the RPM's to whatever RPM you need to be at the speed you're going, and release the clutch.

"Double-clutching" has absolutely no purpose in cars these days. You can just rev-match with the clutch pushed in.
 

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[quote author=Kyle Hadcock link=topic=67972.msg1174727#msg1174727 date=1170096906]
Nope, you can get into first gear at whetever speed you want. Not destroying your transmission once you release the clutch pedal is the problem here. But to get in first gear all you have to do is push the clutch all the way in, raise the RPM's to whatever RPM you need to be at the speed you're going, and release the clutch.

"Double-clutching" has absolutely no purpose in cars these days. You can just rev-match with the clutch pushed in.
[/quote]

I agree with the first part. I have no problems getting into first at < 34mph as long as the clutch is all the way in. Clutch management is what makes the difference in how the car will respond (jerk forward, or gradually lean forward for example). I disagree that double-clutching has no purpose. If you want a completely smooth (and fast) down-shift, it helps. The reason for the blip at neutral is because the input/output shafts aren't connected when the pedal is pushed in. If you "rev-match" with the pedal pushed in, you aren't turning the output shaft at all (even if you're in gear). Personally, I don't double-clutch often because the synchro-mesh along with my shifting technique doesn't require it for normal driving conditions.

As for the problem described by the original poster ... I would personally spend a little more time with first gear on hills. A common trick is to set the parking brake, give it some throttle, release the clutch until it tugs the car just a hair, then release the parking brake. Eventually, you'll be able to take your foot off the brake, give it throttle and release in first gear smoothly and fast enough that the car doesn't even have time to roll back at all. It's all about experience.
 

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[quote author=Kyle Hadcock link=topic=67972.msg1174727#msg1174727 date=1170096906]
Nope, you can get into first gear at whetever speed you want. Not destroying your transmission once you release the clutch pedal is the problem here. But to get in first gear all you have to do is push the clutch all the way in, raise the RPM's to whatever RPM you need to be at the speed you're going, and release the clutch.

"Double-clutching" has absolutely no purpose in cars these days. You can just rev-match with the clutch pushed in.
[/quote]

it doesn't matter if you rev match perfectly, if the input, counter, and output shafts in the tranny doens't spin at same speed for that gear, it is not going to engage. You can rev match all day long but in the end it's the synchro that's helping change gears by matching the shafts speeds to the output shaft, rev matching helps engage the engine to the tranny smoothly.

1st gear is harder to engage because of the etra low gear ratio, and it takes more time for the syncro to speed up the input shaft before the gear engages, which means you can't just shuff the shifter towards 1st and expect everything to happen instantly.
 

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Discussion Starter #13
[quote author=Kyle Hadcock link=topic=67972.msg1174727#msg1174727 date=1170096906]
As for the problem described by the original poster ... I would personally spend a little more time with first gear on hills. A common trick is to set the parking brake, give it some throttle, release the clutch until it tugs the car just a hair, then release the parking brake. Eventually, you'll be able to take your foot off the brake, give it throttle and release in first gear smoothly and fast enough that the car doesn't even have time to roll back at all. It's all about experience.
[/quote]
Not quite my problem (although it is a tad for steep hills since I'm pretty new). My problem is starting from flat ground moving about 25mph in 2nd then climbing a steep hill in which I sometimes need to go slow causing my car to bog so I need to get it into 1st.


I tried double clutching out today. Luckily the line into the garage wasn't too far up the steep part of the spiral yet so I was able to try double clutching without fear. It worked, although I had to nudge the shifter in a bit, but not force it. Letting off the clutch was a bit jerky but I'm sure I'll get used to it after a couple more tries.

I tried it out when comming up to my house garage though and had a little problem. I slowed down when I was approaching my house so the garage had time to open. I was traveling somewhere around 10mph and did the double clutching. For some odd reason, after I let off the clutch in first, my tach bobbed up and down a little. I doubt it could be slipping since I only have 1200miles on it. Can someone pinpoint the exact reason so I don't screw anything up?

Thanks everyone for the help :klavergreg:
 

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[quote author=Kyle Hadcock link=topic=67972.msg1174727#msg1174727 date=1170096906]
[quote author=azazel1024 link=topic=67972.msg1174641#msg1174641 date=1170094344]
First gear has a shift interlock on it. It will not allow you to engage the gear if the speed differential between the 1st gear and the output shaft and the input shaft are beyond a certain amount (I am 99% sure on this, a lot of cars have this). What this basically means is that you will not be able to shift into first gear going more then about 5mph unless you double clutch to engage 1st gear. [/quote]

Nope, you can get into first gear at whetever speed you want. Not destroying your transmission once you release the clutch pedal is the problem here. But to get in first gear all you have to do is push the clutch all the way in, raise the RPM's to whatever RPM you need to be at the speed you're going, and release the clutch.

"Double-clutching" has absolutely no purpose in cars these days. You can just rev-match with the clutch pushed in.
[/quote]

yeah that won't work. With the clutch in you are not matching the input shaft speed to the speed of the intermediate and output shafts, you still will have the very large speed differential that prevents engagement of 1st gear. You could be going 30mph and drop the clutch with it in 1st gear and it won't destroy the trans, it will probably break the tires lose and take some life off the clutch, but it does nothing to the synchros. It is having such a large speed differential when engaging a gear that does it.

The ONLY way to take stress off the synchornizers is to double clutch no matter how modern your car is. You can shift clutchlessly if you rev match pretty perfectly, but that is not what you are talking about. You cannot rev match the trans shafts with the clutch in.
-Matt
 

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[quote author=cpham53 link=topic=67972.msg1175713#msg1175713 date=1170126512]
...
I tried it out when comming up to my house garage though and had a little problem. I slowed down when I was approaching my house so the garage had time to open. I was traveling somewhere around 10mph and did the double clutching. For some odd reason, after I let off the clutch in first, my tach bobbed up and down a little. I doubt it could be slipping since I only have 1200miles on it. Can someone pinpoint the exact reason so I don't screw anything up?

Thanks everyone for the help :klavergreg:
[/quote]

How little did it 'bob up and down'? It sounds like you didn't have the revs close enough for the gear you were in, ie, next time in the same situation, tap the gas right before you let the clutch out.

What you are describing sounds to me like the slight engine speed variation caused be the motor mounts going back and forth due to the change of speed in the 2-1 shift.

Sorry I can't explain better, but I think I know what you are referring to.
 

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[quote author=cpham53 link=topic=67972.msg1175713#msg1175713 date=1170126512]
[quote author=Kyle Hadcock link=topic=67972.msg1174727#msg1174727 date=1170096906]
As for the problem described by the original poster ... I would personally spend a little more time with first gear on hills. A common trick is to set the parking brake, give it some throttle, release the clutch until it tugs the car just a hair, then release the parking brake. Eventually, you'll be able to take your foot off the brake, give it throttle and release in first gear smoothly and fast enough that the car doesn't even have time to roll back at all. It's all about experience.
[/quote]
Not quite my problem (although it is a tad for steep hills since I'm pretty new). My problem is starting from flat ground moving about 25mph in 2nd then climbing a steep hill in which I sometimes need to go slow causing my car to bog so I need to get it into 1st.


I tried double clutching out today. Luckily the line into the garage wasn't too far up the steep part of the spiral yet so I was able to try double clutching without fear. It worked, although I had to nudge the shifter in a bit, but not force it. Letting off the clutch was a bit jerky but I'm sure I'll get used to it after a couple more tries.

I tried it out when comming up to my house garage though and had a little problem. I slowed down when I was approaching my house so the garage had time to open. I was traveling somewhere around 10mph and did the double clutching. For some odd reason, after I let off the clutch in first, my tach bobbed up and down a little. I doubt it could be slipping since I only have 1200miles on it. Can someone pinpoint the exact reason so I don't screw anything up?

Thanks everyone for the help :klavergreg:
[/quote]

I don't think you screwed anything up at all, but I do know that it isn't necessary to double-clutch the 3 in any normal driving situation. There are times when sitting still even, you will have to put the car in neutral and release the clutch before being able to shift into any gear. Effectively, that is similar to double clutching; however double-clutching as described by the posters here and in the traditional sense isn't required.
 
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