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#1
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Oh, I never said it was a good idea, just curious to know if anyone was aware of the logic behind the decision to make a second gear start. So, when I start my car, I start in 2nd, and then as I build speed I just go straight into third? What about when I leave my garage: I start in second, put it in reverse and then when I am out on the road put it into Drive. At that point would it be in first or second gear?
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Eric Zacharias '88 300 SEL '64 Ford Falcon '99 Infiniti QX4 |
#2
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It all depends on how hard you push the gas pedal. Put it to the floor and you will find first gear. It's there if you need it.
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2009 CLS550 55,000 2004 ML350 144,000 2004 X5 95,000 2002 X5 165,000 1996 320S 155,000 (sold) 1991 190E 192,000 (sold) 1989 300SE 160,00 (sold) 1984 300D 210,000 owned since 85, (sold) 1984 300SD 160,000 (sold) |
#3
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It will never go into first from a dead stop unless you put the shift lever in 2. You pull the lever down to 2 at a full stop and feel the transmission shift down to first. You'll get wall-climbing torque for a few feet then an abrupt shift to second.
It can go into first automatically if it senses a heavy load as you get moving, even if you don't hit the kickdown switch. Sixto 93 300SD |
#4
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I think a 2.88:1 would be an ideal ratio for a 300SEL with first gear start.
Low gear ratio would be about 10.9:1 (with ~3.8:1 first + 2.88:1) versus the ~3.47:1 + ~2.3:1 (second) making about a 7.9:1 only. So you'd be quicker and probably have better economy as the motor won't be lugged badly getting from a dead stop not to mention drop about 500rpm on the freeway... about 2900 @ 70mph versus closer to 3500rpm @ 70mph. Problem is 2.88:1 was only in the SDLs for the W126 (as I understand) and it'll cost a bit to get a VB converted for the ~6400rpm shift point. I have a few first gear start VBs but I need them, I see them at times. Next time I have a spare I can take it apart to compare with a second gear start to see what's up. ![]() 2.47:1 seems like it'd be too low of a cruise RPM for an M103 in a W126... not enough power to keep it going at 24-2600rpm @ 70mph. But hell, it very well could for all I know.
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I'm not a doctor, but I'll have a look. ![]() '85 300SD 245k '87 300SDL 251k '90 300SEL 326k Six others from BMW, GM, and Ford. Liberty will not descend to a people; a people must raise themselves to liberty.[/IMG] |
#5
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All European cars (of this era at least) must pass a test for certification in Switzerland whereby they must be able to pull a house trailer from a standing start on a significant grade.
Therefore, they have a first gear not really suited for anything else. Kind of like the old "granny" gear in pickups that you never used unless you were a teenager that didn't know any better.
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Kent Christensen Albuquerque '07 GL320CDI, '10 CL550. '01 Porsche Boxster Two BMW motorcycles |
#6
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The second gear start in the Mercedes of the 80's was done for two reasons. The main reason was fuel mileage (and IIRC there might have been a fractional benefit for emissions), and the other reason was that first is a true stump-puller (for the reasons cited above) and in slick conditions can be tricky; starting in second allows easier control of power and less likelihood of wheelspin. As others have mentioned, first is available through the shift lever, through the kickdown switch if you floor it from rest, and on demand if there's an unusual load sensed.
To the best of my knowledge, it was only done on the larger V8s, due to their exceptional thirst and exceptional torque.
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Craig Bethune '97 SL500, 40th anniversary edition '04 Olds Bravada (SWMBO's) '06 Lexus ES330 '89 560SL (sold) SL--Anything else is just a Mercedes. (Kudos to whoever said it first) |
#7
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Nope. It's on the I6 300, too.
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1989 300 SEL that mostly works, but needs TLC |
#8
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I had my '91 changed to the 1st gear start (with a Bergwerks module), as the 2nd gear start while smooth, didn't give me the instant torque I hoped to get with the 1st gear start. The pedal throw is real long so you have to mash it all the way to the floor to get a full bore 1st gear start, but it's satisfying.
It took me a month to get used to the difference, but now I usually start out slowly and smoothly from a start, and works well too. But it was nice to have the quick response if I'd like it. The 2nd gear start was offered by Mercedes for economy and smoothness.
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![]() 1995 E 420, 170k "The Red Plum" (sold) 2015 BMW 535i xdrive awd Stage 1 DINAN, 6k, <----364 hp 1967 Mercury Cougar, 49k 2013 Jaguar XF, 20k <----340 hp Supercharged, All Wheel Drive ![]() |
#9
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well thanks everyone, I guess that answers that question. I have a nice smooth start and enough power for me, so I guess I have no problems with the 2nd gear start.
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Eric Zacharias '88 300 SEL '64 Ford Falcon '99 Infiniti QX4 |
#10
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Quote:
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It is a truism that almost any sect, cult, or religion will legislate its creed into law if it acquires the political power to do so. Robert A. Heinlein 09 Jetta TDI 1985 300D |
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