Downshift any good ?

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Beau

Lifer
Jun 25, 2001
17,730
0
76
www.beauscott.com
Originally posted by: teddymines
Never downshift on ice or snow! The sudden drag on the tires will cause a quick loss of control, esp on FWD cars.

Change that to "only on fwd cars." Down shifting on ice/snow is a lot safer than braking because the wheels are kept spinning, unlike breaks (minus ABS) which try to stop the wheel completely.

 

jjones

Lifer
Oct 9, 2001
15,424
2
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If you use it in conjunction with braking, tht won't be a problem. But if you get cute, and forget to brake, you could get a rude surprise!
LOL, I probably contributed to more than a few cases of road rage in my time. That reminds me of a few asshole tailgaters I've had back when I used to think I was invincible. Some jerk-off would be late for his decaf espresso or some such and get right on my tail trying to sqeeze a few extra inches off his destination. I'd downshift and dump the clutch without braking and let him get a real close view of my license plate; probably got a real nice view of his life flashing before his eyes too.

Of course the only time I would do that was when I was driving a company vehicle; I wouldn't do that in my car. And me being a family man now, I don't take those kind of risks any more. :)
 

TurtleMan

Golden Member
May 3, 2000
1,424
0
76
Originally posted by: jjones
If you use it in conjunction with braking, tht won't be a problem. But if you get cute, and forget to brake, you could get a rude surprise!
LOL, I probably contributed to more than a few cases of road rage in my time. That reminds me of a few asshole tailgaters I've had back when I used to think I was invincible. q]



LOL, i liked the word invincible :]
 

teddymines

Senior member
Jul 6, 2001
940
0
0
Originally posted by: Beau6183
Originally posted by: teddymines
Never downshift on ice or snow! The sudden drag on the tires will cause a quick loss of control, esp on FWD cars.

Change that to "only on fwd cars." Down shifting on ice/snow is a lot safer than braking because the wheels are kept spinning, unlike breaks (minus ABS) which try to stop the wheel completely.
That's not quite true. When you brake on snow or ice, you apply brakes just before the wheels lock. If they do lock, you can let up on the pedal until the wheels spin again, then apply less brake. The reaction is very quick.

With downshifting on snow or ice, the engine puts a lot of drag on the wheels. You are depending on the ground to try to spin those wheels to overcome the engine drag. In most cases, the engine drag is too much and the wheel will lock up on the snow.

Trust me on this, I've been driving in upstate NY snow for over 22 years.

 

Ultima

Platinum Member
Oct 16, 1999
2,893
0
0
Originally posted by: TurtleMan
let's say im going 80mph , then i downshit into 4th gear , and it rev up to like 4 or 5000 rpm my redline is 6000something
is it overreving ? sometime when i downshift, there is like a force of pulling me back all the sudden , it is like engine got stucked or something , so i don't know if im doing it right or wrong........

What you're talking about is compression. When you let the engine rev high and you're not giving it gas then it will naturally slow down because of the compression in the cylinders and since the engine is connected to the wheels that slows down the car as well. Brake pads are cheap, use your brakes to slow the car. Engine braking is useful in hilly areas to avoid brake fade, but in regular driving there's no need for using excessive compression. Downshifting one gear and braking at the same time should be good.
If you see a red light far ahead of you and you're going at a decent speed don't even downshift, just put it into neutral and coast to the light. You'll save both your gas and your brakes this way.
 

Ultima

Platinum Member
Oct 16, 1999
2,893
0
0
Originally posted by: Jzero
Originally posted by: TurtleMan
let's say im going 80mph , then i downshit into 4th gear , and it rev up to like 4 or 5000 rpm my redline is 6000something
is it overreving ? sometime when i downshift, there is like a force of pulling me back all the sudden , it is like engine got stucked or something , so i don't know if im doing it right or wrong........

If you don't go above redline, you're definitely fine. Most cars these days have rev limiters that would save you from doing much damage anyway.

As for the "force" you feel, it's probably just they way you're shifting. When you hit the clutch, the engine drops back to idle speed and when you downshift and release the clutch pedal, the engine has to jump up to match the gear speed.
You can minimize or eliminate this by reading up and practicing double clutching.

In short, you normally:
Clutch
Downshift
Release Clutch.

When double clutching:
Clutch
Neutral
Release Clutch
"Blip" the gas pedal to rev the engine up to or a little above your target RPM speed
Clutch
Downshift to the appropriate gear
Release the clutch.


When you get good at this, you will be able to downshift without any "feeling." The only indication that you've downshifted is increased drag and the sound of your engine spinning faster.

Be sure to practice this stuff in a parking lot or something first.

Why do you have to release the clutch when it's in neutral? Shouldn't blipping the gas with the clutch pressed be good enough? I mean, it's in neutral anyway with the clutch pressed.

 

CocaCola5

Golden Member
Jan 5, 2001
1,599
0
0
Downshifting can also turn the engine's crank into unsprung weight, if your brakes are top notch this would impede them.
 

mithrandir2001

Diamond Member
May 1, 2001
6,545
1
0
You "should" brake as much as possible (rather than downshift) because it is rather cheap and easy to replace brake pads while clutch replacement is bit more expensive and complex. That said, I downshift a lot because (a) it's fun (b) your engine is typically residing in its powerband so if you need to accelerate quickly, you've got the power at your immediate access.
 

MaDHaVoK

Senior member
Mar 7, 2001
601
0
0
Down shift when you have to, don't use it as your brake! Your brakes are designed to slow you down, your clutch isn't...... besides anyone who says they down shift to save their brake pads is a moron.... obviously they never tried replacing a clutch before.... I will tell you from personal experience, it is 100 times cheaper and easier to replace your brake pads than your clutch.
 

Vadatajs

Diamond Member
Aug 28, 2001
3,475
0
0
Originally posted by: Beau6183
Depends on the situation. If you are going at high speeds and need to slow down gradually (ie: coming off a free way on to an off ramp) then I downshift and let the tranny/engine slow the car and not waste brake pad.

In the same situation I shift to neutral and not waste the clutch. Brakepads are cheaper to replace.
 

SWirth86

Golden Member
Aug 31, 2001
1,939
0
0
Ok, the general opinion seems to be that its more economical to use your brakes instead of downshifting. Thats good, because thats what I always do (its a lot easier), but my dad always says that I should downshift to reduce wear on the brakes.
I only downshift when going up hills, or when the speed of traffice is reduced to a point where the engine starts to strain.
 

brtspears2

Diamond Member
Nov 16, 2000
8,660
1
81
I would post the video of a mis-shift, but damn cyberwings is down.....

If anyone like to see an RSX Type-S misshift, contact me on AIM at PCMMX
 

matsuhisa

Senior member
Aug 14, 2002
289
0
0
you're supposed to downshift. you're supposed to do 50% strictly braking, 50% downshifting so that you can extend the use of both parts longer. if you downshift too much, you'll have to change your clutch but if you brake too much, you'll have to change your brake pads. so use them at the same ratio to extend their lifetime.
 

Thegonagle

Diamond Member
Jun 8, 2000
9,773
0
71
Brake pads are $20-60 a set. A clutch job is $700-2000. Pretty big difference, eh? You want to extend the life of a clutch as much as possible. F--k the brakes!

Use the brakes to slow down, and downshift appropriate to your new, slower cruising speed, or to accelerate.
 

NutBucket

Lifer
Aug 30, 2000
27,177
647
126
Originally posted by: Garfang
Brake pads are $20-60 a set. A clutch job is $700-2000. Pretty big difference, eh? You want to extend the life of a clutch as much as possible. F--k the brakes!

Use the brakes to slow down, and downshift appropriate to your new, slower cruising speed, or to accelerate.

I couldn't agree more.

<-- Just saved $800 in labor by changing the clutch in his Accord himself.