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-Benz Forum > Mercedes-Benz Tech Information and Support > Diesel Discussion

Reply
 
LinkBack Thread Tools Display Modes
  #1  
Old 04-09-2014, 07:55 PM
Registered User
 
Join Date: Dec 2005
Location: Carson City, NV
Posts: 3,850
W126 Front Brake Upgrade

The brakes on my W123 are getting knackered and I'm considering upgrading to W126 vented rotors on the front. However, I've only ever gotten the current non-vented brakes to fade once. I'm wondering if the extra braking ability will really be of use and whether if will justify the slight increase in unsprung weight. Has anyone done back to back testing to see the results of this modification?

__________________
Whoever said there's nothing more expensive than a cheap Mercedes never had a cheap Jaguar.

83 300D Turbo with manual conversion, early W126 vented front rotors and H4 headlights 400,xxx miles
08 Suzuki GSX-R600 M4 Slip-on 22,xxx miles
88 Jaguar XJS V12 94,xxx miles. Work in progress.
Reply With Quote
  #2  
Old 04-09-2014, 11:22 PM
He/Him
 
Join Date: May 2010
Location: DC Metro/Maryland
Posts: 13,244
Quote:
Originally Posted by Skippy View Post
The brakes on my W123 are getting knackered and I'm considering upgrading to W126 vented rotors on the front. However, I've only ever gotten the current non-vented brakes to fade once. I'm wondering if the extra braking ability will really be of use and whether if will justify the slight increase in unsprung weight. Has anyone done back to back testing to see the results of this modification?
Which w126 brake upgrade? 1st Gen w126 SD had the same size rotors as the w123, just vented. 2nd Gen SD had larger rotors, also vented.

If you want to keep your wheels 14" then the 1st gen SD dust shields, calipers, rotors and pads are a decent upgrade to prevent brake fade.
__________________
Onus probandi incumbit ei qui dicit, non ei qui negat

I recondition w123/w126/w124/w140/r107/r129/ steering boxes!


1984 300D "Elsa" odo reset 6/2011 147k
1983 300TD "Mitzi" ~268k OM603 powered
1995 E300 "Adelheid" 262k [Sold]
Reply With Quote
  #3  
Old 04-10-2014, 05:08 AM
Registered User
 
Join Date: Dec 2005
Location: Carson City, NV
Posts: 3,850
I was thinking 1st gen, since I still have the 14" wheels and haven't found a set of 15's.
__________________
Whoever said there's nothing more expensive than a cheap Mercedes never had a cheap Jaguar.

83 300D Turbo with manual conversion, early W126 vented front rotors and H4 headlights 400,xxx miles
08 Suzuki GSX-R600 M4 Slip-on 22,xxx miles
88 Jaguar XJS V12 94,xxx miles. Work in progress.
Reply With Quote
  #4  
Old 04-10-2014, 06:01 AM
t walgamuth's Avatar
dieselarchitect
 
Join Date: Apr 2005
Location: Lafayette Indiana
Posts: 38,613
The first gen upgrade is bolt on. I probably would only do it if I had a wagon with the extra weight. The unsprung weight difference is probably not enough to notice in ride quality (and I am picky about that).
__________________
[SIGPIC] Diesel loving autocrossing grandpa Architect. 08 Dodge 3/4 ton with Cummins & six speed; I have had about 35 benzes. I have a 39 Studebaker Coupe Express pickup in which I have had installed a 617 turbo and a five speed manual.[SIGPIC]

..I also have a 427 Cobra replica with an aluminum chassis.
Reply With Quote
  #5  
Old 04-10-2014, 08:54 AM
winmutt's Avatar
85 300D 4spd+tow+h4
 
Join Date: Apr 2006
Location: Atl Gawga
Posts: 9,346
I found both upgrades to be fantastic.
__________________
http://superturbodiesel.com/images/sig.04.10.jpg
1995 E420 Schwarz
1995 E300 Weiss
#1987 300D Sturmmachine
#1991 300D Nearly Perfect
#1994 E320 Cabriolet
#1995 E320 Touring
#1985 300D Sedan
OBK #42
Reply With Quote
  #6  
Old 04-10-2014, 11:32 AM
Dr. Sternschnuppe's Avatar
Registered User
 
Join Date: May 2012
Location: CH
Posts: 574
Arrow

N.B.
You must install brakes vacuum booster from 126 also.
And it will really work better.
Reply With Quote
  #7  
Old 04-10-2014, 02:07 PM
DeliveryValve's Avatar
Chairman of my Benz
 
Join Date: Jun 2006
Location: Central California
Posts: 4,159
Quote:
Originally Posted by Dr. Sternschnuppe View Post
N.B.
You must install brakes vacuum booster from 126 also.
And it will really work better.
You'll have to explain in detail why this would be better. I have this setup with the stock w123 booster. The operation and feel has not changed but with the added benefit of minimizing potential fade.


.
__________________
1983 123.133 California
- GreaseCar Veg System


Reply With Quote
  #8  
Old 04-10-2014, 04:01 PM
Registered User
 
Join Date: Dec 2005
Location: Carson City, NV
Posts: 3,850
Quote:
Originally Posted by winmutt View Post
I found both upgrades to be fantastic.
Fantastic how?
__________________
Whoever said there's nothing more expensive than a cheap Mercedes never had a cheap Jaguar.

83 300D Turbo with manual conversion, early W126 vented front rotors and H4 headlights 400,xxx miles
08 Suzuki GSX-R600 M4 Slip-on 22,xxx miles
88 Jaguar XJS V12 94,xxx miles. Work in progress.
Reply With Quote
  #9  
Old 04-10-2014, 05:01 PM
Dr. Sternschnuppe's Avatar
Registered User
 
Join Date: May 2012
Location: CH
Posts: 574
Arrow

Quote:
Originally Posted by DeliveryValve View Post
You'll have to explain in detail why this would be better. I have this setup with the stock w123 booster. The operation and feel has not changed but with the added benefit of minimizing potential fade.


.
The 126 have double-membran vacuum booster.
Reply With Quote
  #10  
Old 04-10-2014, 06:26 PM
DeliveryValve's Avatar
Chairman of my Benz
 
Join Date: Jun 2006
Location: Central California
Posts: 4,159
Quote:
Originally Posted by Dr. Sternschnuppe View Post
The 126 have double-membran vacuum booster.
Yes, but what does that do in terms of braking in a w123?
__________________
1983 123.133 California
- GreaseCar Veg System


Reply With Quote
  #11  
Old 04-11-2014, 05:07 AM
Dr. Sternschnuppe's Avatar
Registered User
 
Join Date: May 2012
Location: CH
Posts: 574
Arrow

Quote:
Originally Posted by DeliveryValve View Post
Yes, but what does that do in terms of braking in a w123?

The vac. booster & master cylinder from 126 on 123 gives more intensive braking. Less effort on brake pedal - more effort on brake pads.


Can an SD brake booster be wedged into a W123?
Reply With Quote
  #12  
Old 04-11-2014, 07:24 AM
t walgamuth's Avatar
dieselarchitect
 
Join Date: Apr 2005
Location: Lafayette Indiana
Posts: 38,613
I had a car with the 126 brakes on it and the brake feel was just fine. Easier is not better in my mind if what you have to begin with is good.
__________________
[SIGPIC] Diesel loving autocrossing grandpa Architect. 08 Dodge 3/4 ton with Cummins & six speed; I have had about 35 benzes. I have a 39 Studebaker Coupe Express pickup in which I have had installed a 617 turbo and a five speed manual.[SIGPIC]

..I also have a 427 Cobra replica with an aluminum chassis.
Reply With Quote
  #13  
Old 04-11-2014, 08:00 AM
Mölyapina's Avatar
User title not in use
 
Join Date: Oct 2012
Location: Chelmsford, Massachusetts
Posts: 4,373
Quote:
Originally Posted by Dr. Sternschnuppe View Post
The 126 have double-membrane vacuum booster.
You guys obviously are missing the point here. Imagine having this discussion with a girl you're trying to impress:

You: Yeah, my car has a double-membrane brake booster.
Her: Um, OK.
You: What's your number?
Her: 9-1-1. Call me anytime.
You: That's funny, you're the third girl I've met tonight with that phone number. Are you guys roommates or something?
__________________
"Senior Luna, your sense of humor is still loco... but we love it, anyway." -rickymay ____ "Your sense of humor is still loco... " -MBeige ____ "Señor Luna, your sense of humor is quite järjetön" -Delibes

1982 300SD -- 211k, Texas car, tranny issues ____ 1979 240D 4-speed 234k -- turbo and tuned IP, third world taxi hot rod

2 Samuel 12:13: "David said to Nathan, “I have sinned against the Lord.” And Nathan said to David, “The Lord also has put away your sin; you shall not die."
Reply With Quote
  #14  
Old 04-11-2014, 08:37 AM
Registered User
 
Join Date: Dec 2012
Location: Albuquerque, NM
Posts: 173
brake upgrade

I am exactly where you are now... on a recent trip up into the San Juan Mountains of SW Colorado in the 300D (Ouray, CO) I experienced serious brake fade. There was a lot of climbing and braking as we ascended to Molas pass heading north out of Durango on 550. My brakes started out smooth, but after enough braking to experience serious fade, they eventually started rumbling on hard application.. In the picture below you can see the new Bosch non-vented rotors that I installed just 1000 miles ago. I am a machinist and I cut the oval grooves on them to imitate the pattern that I used to buy for my Audi A6 4.2 - but they are not working out Not only am I experiencing brake fade, but the groove pattern is causing rotor distortion under heat stress.



I decided to upgraded to vented rotors from an SD of similar vintage, and I will not machine or drill the rotors next time. I have the upgrade components mentioned above that I took off a 1983 W126, and look forward to fade-free & low stress motoring in the mountains. I have no doubt that the vented rotors will be adequate.
Reply With Quote
  #15  
Old 04-11-2014, 09:31 AM
winmutt's Avatar
85 300D 4spd+tow+h4
 
Join Date: Apr 2006
Location: Atl Gawga
Posts: 9,346
Quote:
Originally Posted by Skippy View Post
Fantastic how?
Better braking, less fade. There is not a whole lot of added weight going from solid to vented....

__________________
http://superturbodiesel.com/images/sig.04.10.jpg
1995 E420 Schwarz
1995 E300 Weiss
#1987 300D Sturmmachine
#1991 300D Nearly Perfect
#1994 E320 Cabriolet
#1995 E320 Touring
#1985 300D Sedan
OBK #42
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




All times are GMT -4. The time now is 03:14 AM.


Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2024, vBulletin Solutions, Inc.
Search Engine Optimization by vBSEO 3.6.0
Copyright 2024 Pelican Parts, LLC - Posts may be archived for display on the Peach Parts or Pelican Parts Website -    DMCA Registered Agent Contact Page