w126 first gen on a w123
w126 first gen on a w123
MB w123's ) all have solid rotors. I've had two cars that had small issues with the calipers sticking and then the fluid "boiled" and I had excessive brake fading. That can be scary. I've found out that the first gen w126 (280se/l, 380se/l and 500se/lEDIT- and on the 300sd) calipers and rotors can be swapped directly into a w123- it's plug and play. You must swap both the calipers AND rotors. You will not get more braking power but the w126 is vented and the w123 is solid- so you will have more cooling- less chance of brake fading....
Here is the w123 rotor
and here is the w126 rotor
Better braking is needed when you have more HP....
If you don't want to go the used parts route, you can order rebuilt calipers and new rotors and use your old calipers for the core charge.
IIRC later 126's a slightly larger disc was used. IIRC, the last year W126 500 series had some a lighter caliper as well.
This upgrade is one of many on the list for me to do.
Have you guys seen the newer ATE discs? They have a "wear detector" that is basically 2 rounded squares grooved into the surface. Practically slotted. I will probably go with the ATE unless I upgrade to the vented.
pgringo i would not go with cross drilled. they are prone to cracking. even high dollar cross drilled end up cracking. i know a porsche club track racer who claims to have seen many. slotted and maybe cryo hardened is the goods.Slotted are available as well iirc.
pgringo i would not go with cross drilled. they are prone to cracking. even high dollar cross drilled end up cracking. i know a porsche club track racer who claims to have seen many. slotted and maybe cryo hardened is the goods.Slotted are available as well iirc.
Are the 126 calipers a piston on either side as well? using the same principle as the 123, or do they use a slide?
AFAIK, they are the same as the 123, just larger. It has been over 8 months since I seen my calipers.
Aha! I see. This sounds like a great upgrade, especially since I am kind of experiencing the same kind of brake fade.
This may sound ridiculous, but several times I have read the word AFAIK on this forum and for some reason, assumed each time it was someones name!
Now I know better.
I just found a '86 126 in the junk yard, it is a 420 and it is all there. How much of the brakes should I use from it, calipers/rotors & lines and anything from the rear? Hey does it have a LSD that I could use in my CD, if I didn't have 15" and 16" rims I would get the 15" chrome rims off of it.
(08-19-2009, 06:07 PM)Motorhead I just found a '86 126 in the junk yard, it is a 420 and it is all there. How much of the brakes should I use from it, calipers/rotors & lines and anything from the rear? Hey does it have a LSD that I could use in my CD, if I didn't have 15" and 16" rims I would get the 15" chrome rims off of it.
(08-19-2009, 06:07 PM)Motorhead I just found a '86 126 in the junk yard, it is a 420 and it is all there. How much of the brakes should I use from it, calipers/rotors & lines and anything from the rear? Hey does it have a LSD that I could use in my CD, if I didn't have 15" and 16" rims I would get the 15" chrome rims off of it.
(08-19-2009, 06:47 PM)DeliveryValve So you'll need to get the spindle/steering knuckle, rotors, backplate and calipers. Maybe the lines if they look new.
(08-19-2009, 06:47 PM)DeliveryValve So you'll need to get the spindle/steering knuckle, rotors, backplate and calipers. Maybe the lines if they look new.
I think the backing plates are the same at least they where on my w123 and w116
(08-19-2009, 06:56 PM)ForcedInduction(08-19-2009, 06:47 PM)DeliveryValve So you'll need to get the spindle/steering knuckle, rotors, backplate and calipers. Maybe the lines if they look new.
You shouldn't need the spindles. Just the rotors, calipers and back plate.
You'll also need at least 15" wheels for them to fit.
(08-19-2009, 07:29 PM)willbhere4u I think the backing plates are the same at least they where on my w123 and w116
(08-19-2009, 06:56 PM)ForcedInduction(08-19-2009, 06:47 PM)DeliveryValve So you'll need to get the spindle/steering knuckle, rotors, backplate and calipers. Maybe the lines if they look new.
You shouldn't need the spindles. Just the rotors, calipers and back plate.
You'll also need at least 15" wheels for them to fit.
(08-19-2009, 07:29 PM)willbhere4u I think the backing plates are the same at least they where on my w123 and w116
(08-19-2009, 07:29 PM)willbhere4u I think the backing plates are the same at least they where on my w123 and w116For the wider genI W126 rotors they are, but Motorhead got a set of larger diameter genII brakes instead.
(08-19-2009, 07:29 PM)willbhere4u I think the backing plates are the same at least they where on my w123 and w116For the wider genI W126 rotors they are, but Motorhead got a set of larger diameter genII brakes instead.
ah ok makes seance good to know!
Cool, I guess I will be in Pic-a-part on Sunday morning. I also seen a N/A '79 300 with a center inlet long runner intake, I have to stick to basics right now and get my pile going.
i know the second do not, but do the first gen W126 rotors fit in 14 inch wheels?
edit: kept reading and it sounds like the answer is yes, but with no size increase over the W123 ones, just vents.
(09-26-2013, 04:54 PM)bricktron i know the second do not, but do the first gen W126 rotors fit in 14 inch wheels?
edit: kept reading and it sounds like the answer is yes, but with no size increase over the W123 ones, just vents.
(09-26-2013, 04:54 PM)bricktron i know the second do not, but do the first gen W126 rotors fit in 14 inch wheels?
edit: kept reading and it sounds like the answer is yes, but with no size increase over the W123 ones, just vents.
OK, but don't you have to do rather a lot of braking to overheat the rotors? for racing, or even driving down a mountain, i can understand this; when does it come up for you?
I guess the use of the word "imperative" seems pretty dramatic. But you can have the potential for brake fade at any time in an emergency hard braking situation. Brake fade leads to longer stopping distance.
Couple of examples for my peace of mind i get with vented brakes.. I often drive over the Grapevine on the I5 which sometimes requires avoiding crazy drivers doing the unexpected going down the mountain. I'm also in constant stop and go driving in 100 plus degree ambient temperatures.
This is pretty much normal driving I do, but I would think on the hilly streets of San Fran, you should definitely consider this upgrade. City stop and go driving as well as stopping on a down hill should help with that performance.
.
fair enough. is it well known at what rotors temperature the brakes suffer fade? i have a handheld infrared thermometer and i would like to sample their temperature right after heavy braking to get a sense of the risk here. as far as i know, i have never experienced brake fade in any car, but i could be wrong.
i can't deny that the vented rotor is better, just trying to prioritize other things given my limited bandwidth.
on a somewhat positive note, i squealed the tires for the first time this morning!
Don't know temp but yeah for squealing tires.
Back burner for you I think. Qatar is flat Isn't it? I'd say wait for a need to upgrade. If your calipers go out replace with the upgrade. If you find them cheap in a junk yard get them.
(09-30-2013, 02:33 PM)bricktron fair enough. is it well known at what rotors temperature the brakes suffer fade? i have a handheld infrared thermometer and i would like to sample their temperature right after heavy braking to get a sense of the risk here. as far as i know, i have never experienced brake fade in any car, but i could be wrong.
i can't deny that the vented rotor is better, just trying to prioritize other things given my limited bandwidth.
on a somewhat positive note, i squealed the tires for the first time this morning!
(09-30-2013, 02:33 PM)bricktron fair enough. is it well known at what rotors temperature the brakes suffer fade? i have a handheld infrared thermometer and i would like to sample their temperature right after heavy braking to get a sense of the risk here. as far as i know, i have never experienced brake fade in any car, but i could be wrong.
i can't deny that the vented rotor is better, just trying to prioritize other things given my limited bandwidth.
on a somewhat positive note, i squealed the tires for the first time this morning!
have second generation myself 1991 w126, works great.
looks front tires without problem doing 60mph and with 225/45r17 wheels
Great feeling to have that stopping power
and a tad extra pressure and the rear locks up too, with stock rebuilt calipers and new discs.
I had w116 300sd front and rear calipers/rotors on my 240d turbo project same dimensions but vented. It worked great I got all of it for free off a parts car it was all brand new with less than 100 miles. next time i'll go with the 2nd gen w126 brakes.
What about wagons? I hear they have larger rear calipers?
i think the w115 is supposed to have 38mm calipers at back, while the w123 has 42mm, other than that, i dont know about any other difference, even the late w126, and early w123 are supposed to be the same. at the back.
thanks. i'm afraid i really want the 2nd gen brakes - but still haven't found a wheel that would let me keep the color hubcaps. so i am stuck on this one.
(10-06-2013, 12:09 AM)bricktron thanks. i'm afraid i really want the 2nd gen brakes - but still haven't found a wheel that would let me keep the color hubcaps. so i am stuck on this one.
(10-06-2013, 12:09 AM)bricktron thanks. i'm afraid i really want the 2nd gen brakes - but still haven't found a wheel that would let me keep the color hubcaps. so i am stuck on this one.
(10-04-2013, 07:52 PM)sassparilla_kid What about wagons? I hear they have larger rear calipers?
(10-04-2013, 07:52 PM)sassparilla_kid What about wagons? I hear they have larger rear calipers?
(10-07-2013, 08:33 PM)DeliveryValve(10-04-2013, 07:52 PM)sassparilla_kid What about wagons? I hear they have larger rear calipers?
Yes they have larger pistons, larger than the w116 and w126.
(10-07-2013, 08:33 PM)DeliveryValve(10-04-2013, 07:52 PM)sassparilla_kid What about wagons? I hear they have larger rear calipers?
Yes they have larger pistons, larger than the w116 and w126.
(10-07-2013, 08:33 PM)DeliveryValve(10-04-2013, 07:52 PM)sassparilla_kid What about wagons? I hear they have larger rear calipers?
Yes they have larger pistons, larger than the w116 and w126.
(10-07-2013, 08:33 PM)DeliveryValve(10-04-2013, 07:52 PM)sassparilla_kid What about wagons? I hear they have larger rear calipers?
Yes they have larger pistons, larger than the w116 and w126.
(10-08-2013, 07:46 AM)swampmonkey(10-07-2013, 08:33 PM)DeliveryValve(10-04-2013, 07:52 PM)sassparilla_kid What about wagons? I hear they have larger rear calipers?
Yes they have larger pistons, larger than the w116 and w126.
that was new to me!
good to know, how large? diameter etc?
(10-08-2013, 07:46 AM)swampmonkey(10-07-2013, 08:33 PM)DeliveryValve(10-04-2013, 07:52 PM)sassparilla_kid What about wagons? I hear they have larger rear calipers?
Yes they have larger pistons, larger than the w116 and w126.
that was new to me!
good to know, how large? diameter etc?