Downshifting

[Iliveforthis]

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[frimmelnojerz]

its called downshifting.

[gatorfast]

Originally Posted by Iliveforthis

hey guys just another quick question, any answers are once again- greatly appreciated. with the steptronic trans, after searching through some threads, it seems like a lot of people talk about being on a main road in like 4th gear, then shifting quickly into second, what does that do exactly? give you a boost? just wondering the logic behind it, thanks

Yes, it gives you a boost. Ever push the accelerator in all the way and feel the car rush forward and see the revs shoot up? Thats the car downshifting into a lower gear (i.e. 4th to 2nd).

[Xyloft]

you're basically pushing the car from low RPMs into the power band where you have significantly more HP.

if you go from 4th to 2nd with no gas, you'll feel the car lurch forward as the engine brakes the transmission.

[mistermojorizin]

Originally Posted by Iliveforthis

hey guys just another quick question, any answers are once again- greatly appreciated. with the steptronic trans, after searching through some threads, it seems like a lot of people talk about being on a main road in like 4th gear, then shifting quickly into second, what does that do exactly? give you a boost? just wondering the logic behind it, thanks

it increases your rpms putting you in the "power band". its also good to keep up the rpms during corners, it keeps the suspension settled.

[frimmelnojerz]

my head is about to explode. this cant be a real question.

[1ToBeOn2Wheels]

Basic fundamentals of driving being asked by a 135 owner? I'm a little shocked and confused.

[Mad Dragon]

Originally Posted by 1ToBeOn2Wheels

Basic fundamentals of driving being asked by a 135 owner? I'm a little shocked and confused.

Dealing with a variety of BMW owners all day, every day, this does not surprise me.


We have people complaining about the dinging snowflake that comes and goes. What is it? Is my car broken??

[b2nvs2001]

I have to share a story.

I tried to teach my brother-in-law how to drive a manual. These same types of questions came up : i.e. why low gear, why high gear.

Similarly, I felt the same kind of surprise as some of you when first, he asked those questions, and second when he did not quite understand what I was saying to him.

The same guy, a few weeks later phoned me in horror to ask if it was okay that smoke was coming out of the back of the car (seriously). I guess it really doesn't get cold in LA so he had never seen such exhaust smoke!

Interestingly, this guy, even though he drives an auto, is actually quite a competent driver!

[x97Melbourne]

seriously.....this must be a joke. and, yes it is funny. i like it.

[Robert]

Originally Posted by mistermojorizin

it increases your rpms putting you in the "power band". its also good to keep up the rpms during corners, it keeps the suspension settled.

can you elaborate a little more on why being at high rpm keeps the suspension settled?

[esscolab]

When downshifting it's also essential to use the heel-to-toe technique with the right foot.

[MVF4Rrider]

Originally Posted by Frimmelnojerz

my head is about to explode. this cant be a real question.

Not everyone looks at every corner of a public road as an invitation to practice Schumacher imitations, like me :wink:

But to answer his question of what does it to when downshifting from 4th to 2nd? Answer is, burns more fuel!

[123D-M]

Originally Posted by Frimmelnojerz

my head is about to explode. this cant be a real question.

what he said

[MikeVictor]

Originally Posted by Iliveforthis

hey guys just another quick question, any answers are once again- greatly appreciated. with the steptronic trans, after searching through some threads, it seems like a lot of people talk about being on a main road in like 4th gear, then shifting quickly into second, what does that do exactly? give you a boost? just wondering the logic behind it, thanks

mate one of the other benefits of this is when cornering the engine braking will load up the front of the car more as the nose dips, which helps with steering through corners if you're enjoying a spirited drive.

Also helps you shoot out of said corners like a bat out of hell if you're so inclined to get to the next corner quicker

[chef_geek]

Wow. I guess everyone here was born all-knowing about driving. I am humbled. Far be it to answer a simple question with a simple answer.

[MikeVictor]

Originally Posted by chef_geek

Wow. I guess everyone here was born all-knowing about driving. I am humbled. Far be it to answer a simple question with a simple answer.

:smm7:

[135iUSN]

great info - we are NOT all born race car drivers... and this is my first 'sports' car since my MR2 days of past...

87 NA
88 SC
91 T
93 Turbo - RWD - 200hp / 200 tq - blast to drive

and not in that order, but the 93 was my last and sold in '03

[Iliveforthis]

thanks a lot to all the answers, i am now better informed...

to all the people making fun of the question - you need to get a life.

thanks everyone

[xbook]

Originally Posted by Balls

Not everyone looks at every corner of a public road as an invitation to practice Schumacher imitations, like me :wink:

What??? Then why do they drive???

Taking schumi like turns is the highlight of everyday for me :biggrin:

[gio]

Seriously, when I first learned to drive (at age 16) I had no clue what the automatic transmission was doing in my Honda and there was no way to manually control it. It wasn't until years later that I really thought about it and the concept of downshifting seemed a little bit counter-intuitive to me. The only experience I had in shifting gears was on a bicycle and you certainly don't downshift when you want to accelerate faster then. Now that I've driven a manual transmission for almost 9 years, I take the concept for granted.

The best way to think about it (if you are mathematically minded) is that the power output of an engine is proportional to the engine's torque times the engine speed (RPM). For those of you who remember high school physics "energy" is "force" times "velocity". (E = f*v)

To understand why the engine speed is important, imagine an engine that always produced the same amount of torque no matter how fast it was spinning. With such an engine you could spin it faster and faster and use [really low] gearing to get a virtually infinite force out of that engine. Unfortunately, with real engines the torque drops off at a certain point as the engine spins faster. This means that most engines have an engine speed where they get a peak amount of power out the engine. Ideally we'd always keep the engine at this peak speed and simple change the gearing to get the wheel speed we want but we don't have CVT transmissions.

So this should explain why we downshift. When we downshift, we raise the engine speed up so the engine is in it's powerband (which is usually not much below the redline of the engine). This will give us more power and thus higher acceleration.

[Iliveforthis]

cool thanks a lot gio