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Shifting into First, when?

Discussion in 'Other Off Topic Forum' started by bostonmini, Feb 18, 2004.

  1. bostonmini

    bostonmini Formula 3

    Nov 8, 2003
    1,881
    I know that the general rule is that you never go into first gear before coming to a stop, however my question is, I was told by my brother that I am damaging my sychro-cones by putting the car into first while the clutch is in, "cruising" to a stop sign, and even doing damage putting it in second while keeping the clutch in, while going say, 70, I dont see how this could hurt?
     
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  3. 134282

    134282 Four Time F1 World Champ
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    i was always told that "riding the clutch" is not good, either... i couldn't explain the mechanics to you if my life depended on it, but that's what i've been told... Now, putting the car in neutral and releasing the clutch is a different story, that's cool...

    Whenever approaching a stop sign (and driving a stick), i just put the car in neutral and release the clutch. After i've come to a complete stop at the stop sign (a lost art here on Long Island), i re-engage the clutch, shift into 1st and, well... the rest is history...
     
  4. Mitch Alsup

    Mitch Alsup F1 Veteran

    Nov 4, 2003
    7,067
    Depending upon technique, you brother is either right or wrong. It is easy to tell which: If the nose of the car bobs up or down, or you hear a crunch, or you hear a while of a synchro, then your brother is right.

    However, if you blip the throttle to rev match the engine and driveline, and the gear drop in with a snick just like shifting the box up, and the nose neither bobs up or down, then absolutely no harm is going on.

    Note: clutch should be disengaged (pedal in) only for 1-2 seconds at a time, any longer requirements give you time to put the transmission in neutral and release the clutch pedal.

    I can hit 1st gear as fast as 40 MPH in my F355 under the senario in paragraph 3.
     
  5. whart

    whart F1 Veteran
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    Dec 5, 2001
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    Maybe i'm conservative, but i can't see downshifting into first, which i regard as a launch gear. Rather use the brakes if i am slowing down that much, can't see that balance and attitude of the car will make that much difference at 40-50 miles an hour, which is the upper limit of first in most high performance cars, yes?
     
  6. 96impalaSS

    96impalaSS F1 Rookie

    Dec 8, 2003
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    Yea If im driving a stick I hardly ever get into first unless Im at like a stop light where Im going to be fully stopped.
     
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  8. Schatten

    Schatten F1 World Champ
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    Apr 3, 2001
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    First for me tops at 42mph. That's quite high for what it is. And reverse, oddly enough, it's 50 (GPS verified!).

    I downshift to first quite often, and it needs a good tossing here and there. I find it quite useful in the twisties. But not all cars can shift back into first. Some have a lockout or other mechanism disallowing this practice. So, it depends on the car and transmission.
     
  9. rob lay

    rob lay Administrator
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    Dec 1, 2000
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    Southlake, TX
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    I think what he's asking is if it's bad to shift into first while still moving, even though the clutch is disengaged.

    So he's not engine braking.

    I agree with NNO and Mitch. When coming to a stop on the street it's better for your car to pop in neutral so #1 - You're not engine braking. #2 - You don't have pressure on the clutch system.

    As Mr. Risi says, it's cheaper to replace brakes than an engine/trans.

    So back to the question, even if it's not what he's asking, I would like to know.

    The clutch is engaged so the input shaft isn't being powered by the engine. However, the output shaft is moving because the car is. If you're in the process of moving into a gear in this situation the driven gear is not moving, yet the output shaft is. So even though the clutch is disengaged, I think there would be wear on the syncro cones when going into gear because the driven gear is going at a different speed than the output shaft, so they must "sync".

    I know the above must be correct, because you can still hear a grinding noise when shifting, even with the clutch disengaged. That's the syncro trying to slide over, but hindered by rounded/broken teeth, most likely because of worn syncro cone ridges.

    I know most modern cars block you from first when above a certain speed. That may be more for worrying you might actually engage the clutch while moving than actually worrying about the syncros though.
     
  10. robiferretti

    robiferretti F1 Rookie

    Oct 31, 2003
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    my car does 61 mph in first gear, i'll drop to first if racing at any speed below 40-45. But its very easy to light up the tires in first so it takes finesse to maximize acceleration
     
  11. TimN88

    TimN88 F1 Veteran

    Jun 12, 2001
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    What rob says is correct. Even though the clutch is in, the transmission is still spinning at road speed. The only difference is its disconnectd from the engine. In most cars you either cant put a car into first if you are going to fast- it will either bounce off the sycros or grind, or it wil be hard and require some effort. When i drive a stick car in a normal fasion i dont put it into first unless i come to a complete stop, or am turning onto a hill at a low speed and i need 1st to g oup the hill.
     
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  13. jordan747_400

    jordan747_400 F1 Veteran
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    Dec 9, 2002
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    Interesting thread...how about a situation like this which I encounter pretty much every day. Say Im driving at 50mph and the light up ahead turns red. I put the car in neutral and brake slowly to a stop. However when Im at about 5mph at a really awkward point between first and second, what gear do I shift into? Will popping it into first, blipping the throttle and matching the revs, and releasing the clutch hurt the synchros? I do match revs before I actually engage in the gear. If I put it into second at that speed it requires a bit more easing off the clutch to get in gear without the car sputtering. I never shift into first while moving unless Im in a situation like that though...My first gear only goes up to around 30mph anyway but I usually shift at 3,000 (~15mph). Redline is below 5,500.
     
  14. Mitch Alsup

    Mitch Alsup F1 Veteran

    Nov 4, 2003
    7,067
    so far so good. However, to maximize your chance of coasting through the red period of the light, leave the car in gear and use engine braking. Revert to real brakes only if you actully have to stop or the engine braking is not slowing sufficiently. Also note: begin deceleration the instant you know the light will turn red--this is often before it actually turns red--this gives you more time and distance to perform the red light avoidance manouvers.

     
  15. PeterS

    PeterS Three Time F1 World Champ
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    Jan 24, 2003
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    GUYS: THIS SHOULD BE THE HARD RULE:

    I usually toss the car to nuetral from second gear when approaching a stop sign. The only exception is when Melodie is putting on lipstick. In that case, I will always downshift from second to first gear. At that point, she'll turn to me and all I see is a big line of red lipstick from her lips to her ear. I just laugh my a$$ off!...try it sometime!
     
  16. rob lay

    rob lay Administrator
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    Most the time I can coast to where I need to be, but if I need to get back on the throttle I always use 2nd, unless I came to a complete stop. Most cars you can easily get the car rolling in 2nd.
     
  17. robiferretti

    robiferretti F1 Rookie

    Oct 31, 2003
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    i am king of the rolling stop, i stay in 3rd :)
     
  18. TCM

    TCM Formula Junior

    Nov 10, 2003
    552
    Tyngsborough, MA
    As mentioned earlier, you are doing no damage to the transmission, clutch, or synchros if you are properly rev matching when downshifting at speed. If you are just sticking the transmission in gear with the clutch disendgandged, you are not doing much damage either (although it is better to wait till the transmission accepts the gear-it pops in). If you are just sticking it in gear and releasing the clutch letting the clutch and synchros take up the slack, you are hurting the car.

    Some above mentioned double clutching, it is not needed on today's transmissions (although it is fun to do) because of the advanced synchromesh gears. Single clutch rev matching is fine for most applications but I definately reccommend you learn how to double clutch. There is very few feelings better then exectuting a perfect 5-4-3-2-1 heel and toe, double clutch downshift. Very fun!
     
  19. 134282

    134282 Four Time F1 World Champ
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    LMAO...! Peter, remind me never to do ANYTHING in the passenger seat of your car while you're driving...
     
  20. PeterS

    PeterS Three Time F1 World Champ
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    carbee...Are you telling me you wear makeup? Please explain.
     
  21. ChrisfromRI

    ChrisfromRI Karting

    Jan 28, 2003
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    Foster, RI
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    Chris F
    When I'm Autocrossing in my S2000 at Miata Club events I MUST downshift to first at the two carousels they typically put into the ends of their courses. Their courses are really tight.

    It's simple enough: just heel 'n toe downshift while braking like a banschee to invoke ABS and make it into the tight carousel turn with a bit of understeer, then squeeze the throttle to the floor starting at 5/8 of the way around the carousel and countersteer to control the oversteer.

    This is about a half second faster than leaving it in second and dogging around the carousel. Two carousels are about a full second faster!

    In my 308 GTB QV I would just dog around as it has some more low RPM torque, and the transmission is more expensive to fix...

    Kind Regards. Chris
     

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