Parts Catalog Accessories Catalog How To Articles Tech Forums
Call Pelican Parts at 888-280-7799
Shopping Cart Cart | Project List | Order Status | Help




Go Back   PeachParts Mercedes ShopForum > Technical Information and Support > Tech Help

Reply
 
LinkBack Thread Tools Display Modes
  #16  
Old 03-05-2001, 02:18 PM
Registered User
 
Join Date: Jun 2000
Location: Saugus, CA USA
Posts: 1,989
My vote

Having changed clutches and brakes, my vote goes to using brakes. Last clutch I changed lasted 220,000 miles and took three days to do. I could change lots of brakes in three days.

Using both the engine and the brakes to stop is like stopping a motorcycle where you have seperate controls for the front and back brakes, and you can still downshift.
__________________
5 speed '91 190E 2.6 320,000 mi. (new car, fast, smooth as silk six, couldn't find any more Peugeots)
5 speed '85 Peugeot 505 2.5l Turbo Diesel 266,000 mi. (old car, fast for a diesel, had 2 others)
5 speed '01 Jetta V6 (new wifes car, pretty quick)
5 speed '85 Peugeot 505 2.2l Turbo Gas 197,000 mi. (wifes car, faster, sadly gone just short of 200k )
5 speed '83 Yamaha 750 Maxim 14,000 mi. (fastest)
0 speed 4' x 8' 1800 lb Harbor Freight utility trailer (only as fast as what's pulling it)
Reply With Quote
  #17  
Old 03-05-2001, 03:46 PM
LarryBible
Guest
 
Posts: n/a
blackmercedes,

Since I'm the only Larry that posted before you, I'm doing my best to see where I indicated anything about staying in fifth gear while braking. I simply indicated that it's more economical to stop the car with the brakes than with engine compression.

I'm not a clutch rider by any stretch of the imagination. If I am slowing to a complete stop and know that I'm going to slow to a complete stop, I kick it in neutral and stop the car. When I'm sitting at a light, I sit with gearbox in neutral until the light turns green then slip it in first and go. I'm partial to the throwout bearing, it's as much trouble to replace the throwout bearing as it is to replace the clutch or transmission.

I've never had a manual transmission failure of any kind with this procedure.
Reply With Quote
  #18  
Old 03-05-2001, 04:58 PM
roas
Guest
 
Posts: n/a
Just as I guessed, there are many ways to "skin a cat" and the same applies to this Topic, sorry cat owners.

Even if there was a significant amount of wear involved I would still heel-&-toe regardless. Its part of the whole driving experience to me that is satisfying. I am not hard on my clutches as the last one that was replaced was on my Integra GS-R. I drove that car very hard through every gear change, when the clutch was replaced the mechanic said that the surface was in excellent shape. In fact he asked if I was a "gentle" driver as the surface had a lot of life left in it, the reason for the replacement was because of the a bad bearing BTW.

I was always taught through reading and my Father that it is safer to always be in a gear when moving, for instance if you are braking and coasting out of gear at the same time and then a hazardous situation suddenly appears, you no longer have the instant "power on" option without selecting the gear with a shift change.

I think Jackie Steward also advocates always being in gear before entering any corner, otherwise you will disturb the suspension with a gear selection, I imagine this to be more important at race speeds as you are at the limit already.

Of course, every Heel-&-Toe shift I am referring to also means proper rpm matching, otherwise its not Heel-&-Toe to me, its just plain sloppy.

Reply With Quote
  #19  
Old 03-06-2001, 06:16 AM
Registered User
 
Join Date: Feb 2001
Location: Northumberland, UK
Posts: 1,294
Sounds like the manual transmission might as well be from another planet in the US. As previously noted, there are many ways to skin a cat. High performance or advanced drivers will always use a manual gearbox in a different fashion to the ordinary driver. It is for the former that the heel and toe technique will be important. If you are the latter type of driver, you just won't be interested.

The simple driver is advised to use his brakes to slow down the vehicle to the desired speed, prior to engaging the correct lower gear for his new, reduced, road speed. There are many flaws in this approach, but it is appropriate for a simple driver. It does not matter whether that involves going from 5th to 2nd without stopping at gears in between, so long as gear ration is matched to road speed.

The advanced driver, as he reduces his speed using the brakes, will shift down through the box. This involves the heal and toe technique. With the clutch in, heal of right foot on brake pedal, toe on accelerator (or is it the other way round?), he blips the throttle to bring the engine speed up, while maintaining constant brake pedal pressure. As the clutch comes out, the engine speed should be perfectly matched to brake speed to avoid any sudden change in the balance of the car caused by engine compression. Of course, engine compression contributes to the decelerative effort, but this method ensures that it does so smoothly, without stress on the components, and also ensures that the driver is always in the correct gear for his road speed in the event that he needs to pick up again. Many drivers also prefer to have the engine engaged with the driveline as this enhances both their feeling of control and their actual control of the vehicle. Heal and toe is very difficult and should be practised either on a private road or where you are sure there are no following drivers. I'd be interested to know who can do it; I can't; also a lot of cars do not have their pedals arranged very conducively; the old floor hinged 911 pedals were ideal as are the pedals in a manual BMW.

It has been suggested that a driver may choose to slow the car using only engine braking. This is dangerous as following traffic is given no indication that he is braking. Use of the brake pedal lights the brake lights, obviously; crashing down the gears does not.

There is absolutely nothing wrong with skipping gears on the way up or down the box. The important thing is to be in the correct gear for your road speed and intentions. By way of example, when joining a major road with fast moving traffic from a standstill, a driver may use maximum acceleration in first, second and third gears in order to reach the speed of the traffic as quickly and safely as possible. Having reached that speed, it is entirely appropriate to slot the car from third to fifth or sixth (if your vehicle is so equipped): he has got to the speed he wants to cruise at, so there is no need for intermediate gears. This can be a smooth and efficient way of driving.
Reply With Quote
  #20  
Old 03-06-2001, 10:40 AM
Q Q is offline
Registered User
 
Join Date: Aug 2000
Posts: 839
Using engine braking to slow the car doubles the number of times the throwout bearing has to carry a load, and it also places a heavy opposing load on the drivetrain parts. Lots of automatics do a good job of using engine braking, but they don't do it with the severity of the average manual transmission user who is practicing downshifting for engine braking.

Another thing I would like to point out while speaking of clutch wear is about sitting at a traffic light. Some people will sit at the light with their foot on the clutch for the entire cycle of the light. This will significantly reduce the life of your throwout bearing.
Reply With Quote
  #21  
Old 03-06-2001, 12:31 PM
elau's Avatar
Registered User
 
Join Date: Nov 1999
Location: MD.
Posts: 1,725
Blackmercedes,
Love that "Baby Benz" !!

95 R129
98 W163
Reply With Quote
  #22  
Old 03-06-2001, 01:50 PM
Registered User
 
Join Date: Jun 2000
Location: Saugus, CA USA
Posts: 1,989
And then there's people who sit at red lights on a hill and hold the car with the clutch.
Reply With Quote
  #23  
Old 03-06-2001, 10:23 PM
Registered User
 
Join Date: Jun 2000
Location: Saugus, CA USA
Posts: 1,989
What about shifting without a clutch? I rarely use it on my motorcycle, seldom on an old VW bug I had, and too frequently have to on my Peugeot cause the hydrolic clutch is acting up, although matching engine speed with that diesel is real easy. I've only tryed putting it in gear once with my 190, although I frequently take it out of gear without the clutch.
__________________
5 speed '91 190E 2.6 320,000 mi. (new car, fast, smooth as silk six, couldn't find any more Peugeots)
5 speed '85 Peugeot 505 2.5l Turbo Diesel 266,000 mi. (old car, fast for a diesel, had 2 others)
5 speed '01 Jetta V6 (new wifes car, pretty quick)
5 speed '85 Peugeot 505 2.2l Turbo Gas 197,000 mi. (wifes car, faster, sadly gone just short of 200k )
5 speed '83 Yamaha 750 Maxim 14,000 mi. (fastest)
0 speed 4' x 8' 1800 lb Harbor Freight utility trailer (only as fast as what's pulling it)
Reply With Quote
  #24  
Old 03-07-2001, 12:05 AM
Ashman's Avatar
Registered User
 
Join Date: Sep 2000
Location: Sherman Oaks, CA
Posts: 4,748
Ahh clutchless shifting.

I've done it, but I'm not perfect at it, and I don't have a manual car anymore, so I can't practice it. and even if I did I would not do it more than a few times if that.

But My dad is a pro at it. and can shift smoothly thourghout the gears.

We used to go racing around in a 68 vette he had, using the clutch only for first gear. Though that car did not have a hydraulic clutch either. But the hurst shifter on it was very solid and shifted clean.

Alon
__________________
'92 300CE - Sold
2004 C240 - C7 Wheels - Android Radio
2015 ML350 - P1, Pano, Ash poplar wood, Sport Dinamica interior, Running Boards Keyless go.
Reply With Quote
  #25  
Old 03-07-2001, 08:33 AM
LarryBible
Guest
 
Posts: n/a
I'm amazed that there are so many people on this forum that are old enough that they developed their manual transmission techniques in a car with a sliding gear transmission.

Have a great day,
Reply With Quote
  #26  
Old 03-07-2001, 09:22 AM
Kuan's Avatar
unband
 
Join Date: Jan 2001
Location: At the Birkebeiner
Posts: 3,810
Since the talk is about clutches I have a little story to tell. One time after putting an engine in a P-car we decided to go test drive the thing. The boss said okay let's go, so we went. The thing all of a sudden died on us so we of course check everything and stand around on the side of highway 118 scratching our heads looking real stupid. All of a sudden my boss asks, "did you put gas in the thing?" I'm like.. uh, uh... well errr no! After getting dopeslapped Italian style we get in the car, put it in first gear, crank the starter, and roll down the highway and UP onto the onramp to the light. It was all downhill to the gas station. That was about as close to an electric vehicle as I've ever been! This is one good use for a clutch!

Kuan
Reply With Quote
  #27  
Old 03-07-2001, 11:08 AM
Registered User
 
Join Date: Feb 2001
Location: Northumberland, UK
Posts: 1,294
Clutchless shifting... it's easy enough going up the box, but coming down is another matter altogether!!
Reply With Quote
  #28  
Old 03-07-2001, 05:31 PM
Chicagoland
Guest
 
Posts: n/a
Wow! Thanks for the many replies!

Chicagoland

Reply With Quote
Reply

Bookmarks

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is On
Trackbacks are On
Pingbacks are On
Refbacks are On


Similar Threads
Thread Thread Starter Forum Replies Last Post
83 240D Manual. Does anyone know the Shift Linkage adjustment specs? Carrameow Diesel Discussion 12 04-08-2014 02:31 AM
EXCELLENT Brake Pad Information Here adamb Diesel Discussion 3 10-08-2003 11:46 PM
Is this true? Moisture and MBZ Automatic Transmission Shift Handle haasman Tech Help 6 05-30-2003 04:14 PM
transmission slow shift between 2nd and 3rd oldblue1 Tech Help 6 11-30-2002 06:03 AM
Rough Transmission Shift deuce Diesel Discussion 1 08-06-2002 08:31 PM



All times are GMT -4. The time now is 04:16 PM.


Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2017, vBulletin Solutions, Inc.
Search Engine Optimization by vBSEO 3.6.0
Copyright 2011 Pelican Parts - Posts may be archived for display on the Peach Parts or Pelican Parts Website -    DMCA Registered Agent Contact Page