108 sedan vented brakes on 113 pagoda

[domingo_santo]

I like to ask for help to the ones that have done this brake improvement.  Have you used the 108 backing protector plate (the one behind the disc) or do you use the same of the pagoda?  If the 113 is used, what do you do to allow venting of the disc? been the one for the pagoda for non vented brakes.
Comments are appreciated.

Juan Tomas Santos
Dominican Republic
1982 911SC
1972 350SL
1969 280SL

[ja17]

Hello Juan Thomas ,
The conversion involves replacing the solid brake rotors with ventilated rotors and calipers from a Mercedes V-8, (W108, 280SE 3.5, 4.5 or 6.3) sedan. The ventilated rotors have have the air space (vetilation) between the two surfaces and are wider than the solid rotors so the V-8 caliper must also be used. The brake pads are the same.

I cannot remember for sure but I believe the metal backing plate is the same on all these cars.

Your 280SL looks like it is coming along very nicely! I remember how very different it looked when you showed us the photos in Blacklick last summer!

Hello to your son from us also!



Joe Alexander
Blacklick, Ohio

[jeffc280sl]

I've done the brake rotor and caliper upgrade.  The 108 rotor is thicker than the 113.  It will rub on the back plate of the 113.  In order to use the plate it must be formed to flatten some of the stifning bends in the plate surface.  The venting on the 108 rotor takes place in the interior of the rotor and has not been an issue.

Jeff C.
1970 280SL 4-speed

[domingo_santo]

Ok, I have the new rotors and just one caliper after paying for two, but that is life.
I agree partially with you Jeff, what I think is that when we are at this level of dissambling the backing plate have received so many hits that in a way or another they are always bent in the wrong direction.
But what I am reffering to is that the backing plate is so close to the openings of the disc that I do not figure were the fresh air will come in the disc unless some kind of holes through the backing plate will feed it.
I am trying to post a photo but mine is bigger than 80Kb any help on how to reduce the size of the picture to be posted by this forum?


Juan Tomas Santos
Dominican Republic
1982 911SC
1972 350SL
1969 280SL

[domingo_santo]

Finally it came out. this is the picture I wanted to post. in it there are two modifications to the original backing plate in order to gain more fresh air for the vented rotors.


Download Attachment: new image1.JPG
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Juan Tomas Santos
Dominican Republic
1982 911SC
1972 350SL
1969 280SL

[rwmastel]

Juan,
I don't understand why the holes are near the center of the plate.  Are there holes near the center of the rotor?  I thought the holes were on the end (radial?) and simply created additional surface area to dissapate heat.  Not realy an "air flow", just more surface area.

Rodd
Powell, Ohio, USA
1966 230SL, Euro, Auto, Leather, both  tops
1994 E420

[domingo_santo]

Rodd,
To my knowledge, the air flow is what you want in a vented disc. It is suppose to work as an impeller in a water pump. It moves fresh air from center to outside radially.
On modern sport cars vented and drilled rotors are specify left or right.

Juan Tomas Santos
Dominican Republic
1982 911SC
1972 350SL
1969 280SL

[A Dalton]

quote:Originally posted by domingo_santo


Rodd,
To my knowledge, the air flow is what you want in a vented disc. It is suppose to work as an impeller in a water pump. It moves fresh air from center to outside radially.
On modern sport cars vented and drilled rotors are specify left or right.

Juan Tomas Santos
Dominican Republic
1982 911SC
1972 350SL
1969 280SL

 That is correct  on both concepts.
   Directional flow rotors are quite common now. You can tell by looking down the rotor cavity/slots. If they angle  off-center of the rotor , they are directional and r/l specific.  If the slots are straight with C/L of rotor , they are not drirectional.
The more air you get at the center , the more flow gets expelled out the circumference .....no air in , no air out.

[rwmastel]

OK.  I guess I've never looked that close at a vented rotor.  It's been a while, so I apparently I just don't recall the holes near the center of the rotor.  Learn something new every day!

Rodd
Powell, Ohio, USA
1966 230SL, Euro, Auto, Leather, both  tops
1994 E420