2010-2014 Mustang Information on The S197 {GenII}

Opinions on Engine Braking / Downshifting?

Thread Tools
 
Search this Thread
 
Old Apr 2, 2013 | 05:40 PM
  #1  
dontOverSteer's Avatar
Thread Starter
Member
 
Joined: April 22, 2012
Posts: 44
Likes: 0
Opinions on Engine Braking / Downshifting?

I've heard two big arguments: for and against. What do you think?

To clarify...

Argument in favor of Engine Braking:
Reduces wear and tear on the rotors and pads. Engines that are not accelerating will have a retarding and resisting affect on forces applied to them, such as the movement of the car. Supposedly, the transmission and engine should be able to withstand force in any direction, whether applied from the engine to the wheels or the wheels to the engine.
Two theories: down-shift one gear at a time, or jump a few gears to get a greater braking effect.

Argument against Engine Braking:
The transmission is designed to deliver power from the engine to the wheels, and not the other way. Down-shifting increases wear and tear on the clutch which will always cost more than new pads and rotors. There is less control over speed compared to regular braking and some people find the sound loud and annoying.

So, what do you think? Do you down-shift to slow yourself down? Do you only brake normally?
Reply
Old Apr 2, 2013 | 06:09 PM
  #2  
tukatz's Avatar
Cobra Member
 
Joined: January 4, 2013
Posts: 1,418
Likes: 118
From: Frisco, TX
My Mustang is an automatic, but with other cars (Honda S2000, Morgan) I would downshift as I approached a curve when running through twisties. It was more a matter of being in the right gear to accelerate out of a curve than for engine braking. No question that rotors and pads are way cheaper to replace than clutches. I've heard arguments for avoiding skipping gears both up and down.
Reply
Old Apr 2, 2013 | 06:42 PM
  #3  
mikerob's Avatar
V6 Member
 
Joined: December 18, 2006
Posts: 64
Likes: 0
From: Central Texas
I don't do it to slow down so much, moreso to stay in the power band in case I have to accelerate. Once I get to 2000 rpms slowing down i'll single clutch/rev match down a gear and a little breaking after the downshift if needed. If you must downshift heel/toe would be ideal (wish I could but my feet are huge lol). Although I would never let wear items dictate the way I like to drive my car unless the wear was extreme.
Reply
Old Apr 2, 2013 | 06:54 PM
  #4  
2012GTCS's Avatar
Cobra R Member
 
Joined: June 24, 2011
Posts: 1,570
Likes: 0
From: Long Island
I do it. Mostly to hear the exhaust lol but for the other reasons mentioned as well.

I've heard of people saying they did it for over a 100k miles with no I'll affects.
Reply
Old Apr 2, 2013 | 07:10 PM
  #5  
tukatz's Avatar
Cobra Member
 
Joined: January 4, 2013
Posts: 1,418
Likes: 118
From: Frisco, TX
Originally Posted by mikerob
single clutch/rev match down a gear
Good point, Mike, and one I forgot to mention. Matching revs will go a long way in limiting excess wear on the clutch and gearbox.
Reply
Old Apr 2, 2013 | 08:14 PM
  #6  
racksteris's Avatar
GT Member
 
Joined: October 7, 2012
Posts: 198
Likes: 0
From: Clermont, FL
Originally Posted by tukatz
My Mustang is an automatic, but with other cars (Honda S2000, Morgan) I would downshift as I approached a curve when running through twisties. It was more a matter of being in the right gear to accelerate out of a curve than for engine braking. No question that rotors and pads are way cheaper to replace than clutches. I've heard arguments for avoiding skipping gears both up and down.

Your auto will do it in sport mode. The only mode I LIKE to drive my mustang in.
Reply
Old Apr 2, 2013 | 09:05 PM
  #7  
GreenCars's Avatar
Mach 1 Member
 
Joined: June 6, 2012
Posts: 963
Likes: 0
From: SC
I prefer to downshift to be like was said in the power band for the speed when I can accelerate again. If its a loft slow down I tend to slow down with both gears and braking. A quick stop will always be the brakes.. If I did not want to be shifting up or down I would have purchased a auto.. I have been driving for 40+ years and never wore a clutch out prematurely from the way I drive. My 01 ranger had 135K miles when I sold it and the clutch was still rock solid.
Reply
Old Apr 2, 2013 | 09:31 PM
  #8  
lsxjunkie's Avatar
Bullitt Member
 
Joined: February 25, 2013
Posts: 394
Likes: 2
Don't think about it so much. I brake late and blip the throttle down the gears like I'm coming in hot to the Corkscrew. That's the real reason I bought manual. Done it on all my stick cars. You'll be fine.
Reply
Old Apr 3, 2013 | 02:13 AM
  #9  
Jcint's Avatar
Bullitt Member
 
Joined: October 20, 2010
Posts: 250
Likes: 0
From: West palm beach
If your not downshifting in your 6 speed Then you really never needed a 6 speed ( get an auto) Been driving manual for over 30 years. NEVER had any issues with premature Clutch wear or transmission wear. I normally cycle down 5,4,3 and keep the revs low but ready to GO!
Reply
Old Apr 3, 2013 | 03:56 AM
  #10  
wheelman's Avatar
Shelby GT350 Member
 
Joined: January 24, 2012
Posts: 2,352
Likes: 2
Rev matching good, excessive engine braking bad. Ive torn up clutches in 05-09s though the new ones are better and its easier in a 6 speed than a 5. Just don't get the RPMs too high when downshifting and blip the accelerator a little when needed to give yourself a little range to work with. Note that on public roads others will think your just revving for sh*ts & giggles.
Reply
Old Apr 3, 2013 | 11:33 AM
  #11  
SennaF1's Avatar
V6 Member
 
Joined: November 1, 2012
Posts: 52
Likes: 0
From: Bethesda, MD
If I'm just driving around town, I don't engine brake or aggressively downshift. Pads/rotors are wear items, other pieces of the drivetrain not so much (clutch CAN be, but I don't really WANT it to be ).

For "spirited" driving, I'm not sure what you'd be doing if you're not rev-matching downshifts. I downshift based on the acceleration I need. There's no need to downshift sequentially through all the intermediate gears (and it's often counter-productive). If I'm approaching a 3rd gear corner in 5th, the sequence of events is brake for corner -> heel & toe downshift directly into 3rd -> turn in -> accelerate out in 3rd. There's no reason whatsoever to go through 4th in a non-sequential gearbox.

Last edited by SennaF1; Apr 3, 2013 at 11:34 AM.
Reply
Old Apr 3, 2013 | 12:41 PM
  #12  
AzPete's Avatar
Cobra Member
 
Joined: December 7, 2010
Posts: 1,124
Likes: 6
From: Panama City, Fl.
Yep...always downshift no matter what type driving I do. Always have...always will....it is just part of the fun of driving manual transmission car.
Reply
Old Apr 3, 2013 | 03:56 PM
  #13  
Xar's Avatar
Xar
Mach 1 Member
 
Joined: June 10, 2012
Posts: 748
Likes: 5
From: Southern Oregon
Originally Posted by AzPete
Yep...always downshift no matter what type driving I do. Always have...always will....it is just part of the fun of driving manual transmission car.


same for me.
Reply
Old Apr 4, 2013 | 05:51 AM
  #14  
WhiteWinged's Avatar
V6 Member
 
Joined: February 22, 2013
Posts: 59
Likes: 0
Originally Posted by Xar


same for me.
I do it to an extent but you have to be very careful not to stretch your rods by doing it downhill at excessive rpm ect.
Reply
Old Apr 4, 2013 | 07:04 AM
  #15  
lsxjunkie's Avatar
Bullitt Member
 
Joined: February 25, 2013
Posts: 394
Likes: 2
Originally Posted by WhiteWinged
I do it to an extent but you have to be very careful not to stretch your rods by doing it downhill at excessive rpm ect.
Ummm no. If that were true, every car ever to enter Turn 2 at Laguna Seca would have stretched its rods. Rods GROW with heat, as do pistons, heads, and the block, but not enough to run into PtV clearance issues unless you're running cams with massive lift and duration. If you money shift the car and run it up to 10500, sure you might break a rod bolt or possibly oval out a bearing.

Stock bottom end and street driving? You're fine.

Last edited by lsxjunkie; Apr 4, 2013 at 07:18 AM.
Reply
Old Apr 4, 2013 | 07:06 AM
  #16  
WhiteWinged's Avatar
V6 Member
 
Joined: February 22, 2013
Posts: 59
Likes: 0
Originally Posted by lsxjunkie
Ummm no. If that were true, every car ever to enter Turn 2 at Laguna Seca would have stretched its rods. Rods GROW with heat, as do pistons, heads, and the block, but not enough to run into PtV clearance issues unless you're running cams with massive lift and duration.

Stock bottom end? You're fine.

Lol just because you dont understand it doesnt mean its not true look it up. Lol also hilarious you compare a race car to a normal street powder rod lol
Reply
Old Apr 4, 2013 | 07:19 AM
  #17  
GreenCars's Avatar
Mach 1 Member
 
Joined: June 6, 2012
Posts: 963
Likes: 0
From: SC
Originally Posted by WhiteWinged
Lol just because you dont understand it doesnt mean its not true look it up. Lol also hilarious you compare a race car to a normal street powder rod lol
To compare a race car to stock is done a lot because that is the testing ground for things that more than likely make it to production anyway. Just to throw this out there. but don't autos downshift as well as you decrease in speed? just saying.
Reply
Old Apr 4, 2013 | 07:25 AM
  #18  
WhiteWinged's Avatar
V6 Member
 
Joined: February 22, 2013
Posts: 59
Likes: 0
Originally Posted by GreenCars
To compare a race car to stock is done a lot because that is the testing ground for things that more than likely make it to production anyway. Just to throw this out there. but don't autos downshift as well as you decrease in speed? just saying.

Let me put it this way. Does your Piston pull your crank or your crank pull your piston? Your crank pulls the piston down under heavy decell since the rod in our cars are made of powder material not forged like a race car they have no memory meaning all it takes is one time for them to be pulled to hard. This happens every day will all sorts of cars you can even measure how bad its getting by putting your pistons at TDC and using as traight edge and feeler gauge. Once the memory is lost to an extreme your piston will bend valves. Its really simple
Reply
Old Apr 4, 2013 | 07:33 AM
  #19  
lsxjunkie's Avatar
Bullitt Member
 
Joined: February 25, 2013
Posts: 394
Likes: 2
Originally Posted by WhiteWinged
Lol just because you dont understand it doesnt mean its not true look it up. Lol also hilarious you compare a race car to a normal street powder rod lol
I was referring to normal street cars. People run those on road courses too. All rods stretch. Engines are designed around that. What you're talking about is stretch beyond tolerance. Powdered metal, forged aluminum, billet steel, I've never heard of one in an OE bottom end stretching to the point of PtV contact or failure due to high rpm off throttle driving.
Reply
Old Apr 4, 2013 | 07:40 AM
  #20  
WhiteWinged's Avatar
V6 Member
 
Joined: February 22, 2013
Posts: 59
Likes: 0
Originally Posted by lsxjunkie
I was referring to normal street cars. People run those on road courses too. All rods stretch. Engines are designed around that. What you're talking about is stretch beyond tolerance. Powdered metal, forged aluminum, billet steel, I've never heard of one in an OE bottom end stretching to the point of PtV contact or failure due to high rpm off throttle driving.
Thousands of Semi drivers ford f150 drivers focus drivers mustang chevy 350 ect ect. You name it there has been thousands of incidents almost all of them are manual drivers downshifting downhill. I just had a guy bring one in Tuesday on a chevy 350 and last week on a focus. Its entirely possible common sense dictates not to slam the needle but people it only takes once.
Reply



All times are GMT -6. The time now is 09:04 PM.