Brake System Upgrade
 

This will be an ongoing thread detailing the complete overhaul of the brake system in my '67 Estate. Currently my brakes are horrible and since it's my daily driver I should have done this back when I bought it March. Oh well, there's no time like the present. Here's what I have planned:

Dual circuit master cylinder
New stainless hardline throughout
Braided stainless lines up front
Adjustable bias valve
Front calipers rebuilt
Disc brake rearend from an 1800
Brake light switch converted from hydraulic to pedal-mount type
Build a custom LED conversion for the rear brake lights


I have yet to order any of the major stuff since I'm still narrowing it down to a few options/brands. The 1800 rear might be difficult to find but I'm hopeful somebody we be able to ship me one if I can't get one within driving distance. This will be a pretty big project but I'm excited nonetheless.

Step one was fixing all the play in my brake and clutch lever arms. I'm not sure why but so many car manufacturers don't seem to comprehend the concept of load bearing area. I've seen elongated pivot holes on every car I've ever worked on. Why is this? Is it merely for cost savings in materials or is it to keep you coming back for replacement parts? Even worse I see a lot of things pivoting on the threaded part of a bolt, which is just plain stupid. Here are two pics to show the elongated pivot holes I'm talking about. You can see that the clevis pins have both been machined down by the massive force concentrated by the knife edges:

http://img69.imageshack.us/img69/298...wornlevers.jpg

http://img263.imageshack.us/img263/8...wornclevis.jpg




I always use bolts with a shoulder that's long enough to completely support the pivoting pieces. Sometimes I have to use extra washers to make this possible but so be it. Ideally I like to also increase the load bearing area as much as is practical. For my pedal arms I hand filed then drilled out the pivot holes to 3/8"(9.5mm) and then welded in a short section of stainless steel tube with an ID of 5/16"(7.9mm). This increases the load bearing area to the full width of the pedal arm instead of just at the thin edges of the arm tube itself. Here's a pic of the SS tube being tacked in:

http://img214.imageshack.us/img214/1963/dsc02231.jpg




The clevises for the brake and clutch master cylinder rods also got the treatment. I hand filed the oblong holes round again then drilled them out to 15/32"(11.9mm). I then machined some 5/8"(15.9mm) steel rod to have a 15/32"(11.9mm) lip to fit the clevises as well as a 5/16"(7.9mm) bore for the pivot bolt. Each side is about 3/8"(9.5mm) deep so the load bearing area is about 3/4"(19.05mm) per clevis now instead of 1/4"(6.4mm) each.

http://img195.imageshack.us/img195/9128/dsc02244ag.jpg




Here's the group shot of the finished modified parts:

http://img682.imageshack.us/img682/8837/dsc02254l.jpg




And here's everything re-installed on my car. You can see that I had to significantly turn down the head of the SS pivot bolt on the brake arm for firewall clearance:

http://img36.imageshack.us/img36/2172/dsc02259e.jpg




There is very little play in the clutch and brake arms now, but some play remains due to the worn out rod couplers on the master cylinders. Once they are both replaced the whole system should be nice and tight, even decades from now hopefully. It's the little things like this that make a vehicle much more pleasant to daily drive IMO, but can take an entire day to do right.

Peace,
Derek.

Derek

This is fantastic, well done man! I can really appreciate this. Very impressed!

Phil Singer on The Brick Board built the La Carrera Pan America Apple Farmer Racing 122 and swopped in an 1800 rear end. You should get hold of him if you need any info to make life and R&D simpler.

Dylan

Good job! I like to see a car done right.
About the stainless braided hoses though, can you now buy DOT approved ones? They use to be illegal on road cars a few years ago, but I haven't kept up. Something to do with not being able to inspect the hose rubber itself come MOT time.

Thanks for the nice comments guys. :cool:

Dylan,

Thanks for the heads up on the 1800 rear end car. I'll get in contact and see where it leads me.


asneddon,

DOT-approved braided SS brake lines are indeed available for the 122, at least I know that IPD sells them. I'm still debating if I want to deal with replacing them often though. I might just stick with OEM lines for their longer life. Here's a wiki on brake lines with a good amount of info.

Proper job!

Were you not etmpted to put bearing races in instead. ;-)

You'd have a fright if you saw the brake pedal linkage on a RHD P1800 ...

jimbo1593,

I considered that, but I wanted to keep things simple this early on since I'll be fabricating an entirely new pedal assembly. When that time comes though I do want to have bushings on everything that pivots. I'll machine them from either oil-impregnated sintered bronze or Delrin plastic.


Trommel,

Sounds bad, care to post a pic? :)


I found an excellent 9 page tech article explaining all the things to consider when doing custom braking system design. After reading it I'm convinced that a fully manual dual master cylinder/balance bar setup is the way to go for my wagon. I've been wanting to try this kind of setup for years and now is the perfect chance to do so. I'll probably use this pedal assembly from Wilwood Engineering to make it easier. To line up properly I'd have to fabricate longer, 14" pedal arms for it though.

Good link.

This is the best picture of a RHD car I could find:

http://pds.exblog.jp/pds/1/200703/10...48_1425794.jpg

Wow, yeah with 6 pivots points that could get real bad over time. :)


So according to my dated Haynes repair manual the stock front calipers in my '67 single circuit Amazon are 3 piston type with 2x 1.5" and 1x 2.125 pistons each. Also the '70 to '73 1800 disc brake rear end I'll be using has 2 piston calipers with 2x 1.422" pistons each. I won't know if these numbers are accurate until my caliper rebuild kits arrive, but I emailed Wilwood Engineering and with the above caliper piston specifications they recommended a 7/8" bore for the front master cylinder and 1" for the rear when using a 6.25:1 or 6:1 pedal ratio. This should hopefully allow enough bias adjustment using just the balance bar that I won't need a separate adjustable bias valve. Also the stock clutch and brake pedal arm spacing is about 4.75"(120.7mm) and the Wilwood triple master cylinder pedal assembly is around 3.93"(99.8mm) spacing so it should fit nicely between the steering column.

How will you mount the Wilwood pedal assembly? Will the master cylinders end up in the engine bay or in the car? I'm curious as i need to do the same thing as i have converted my Wagon to P1800ES disc rear end and big Brembo calipers on the front.

Are not changing the front calipers? 4 pot 131 (68 -70) calipers pull up much better than the single cuircit 3 pots.

Ideally the new pedal assembly will mount where the stock master cylinders are now, but as low as possible. The one I was looking at by them (that I linked to above) would put the master cylinders in the engine bay, like the stock setup. However, the Wilwood pedal arms are much shorter than our stock pedal arms so I'm worried they won't be able to reach down far enough to work properly. I don't want to have to modify my firewall to make it work so I'm going to build a rough scale model of this Wilwood pedal assembly out of 1/4" plywood to see if it will all fit properly or not.

So if it won't work then option two will be to not use the Wilwood assembly at all and just make a new custom brake pedal arm. This custom arm would be the stock 15" length, would pivot from the stock top position, but would have the master cylinder pivot point at around 2.5" instead of the stock 3.12" to change the pedal ratio from 4.8:1 up to 6:1 ratio, and would have a large smooth bore tube welded in to allow the Wilwood balance bar to be used. Then the two new brake master cylinders would just need to be mounted about 5/8" higher up than the stock one. Honestly I'm kind of leaning towards this option since it would still look very stock and I could use the $200 that the pedal assembly would cost and put it towards other parts.

I'm interested in the front Brembo calipers you mention. Are they a readily availible bolt on from Brembo? Do you run stock rotors with them? If so a part number would be awesome. :)



It's been pretty hard finding information on the dual circuit calipers. I'm assuming these are them for sale? Would they they bolt onto my car without problems? Do these calipers have the dual inlets designed for the dual line systems or are they single input type? Any info you can provide would be great. I'd really like to upgrade my front calipers as much as possible considering that I'm going all out everywhere else at this point.

That should be the one.It will bolt on to the original fixing on the hub.It does have twin pipes on it but You can just T them togther.

When I have these calipers rebuilt I cange the pistons for slightly bigger ones to give slightly better braking.

If you read through my thread you will find details of my brake caliper and rotor
upgrade

http://www.volvoforums.org.uk/showthread.php?t=56733

I would be very interested in your balance bar brake pedal design. I dont think there is any room to mount the Wilwood assembly lower down. The pedal could be modified in length but that would give a ratio about 8.5:1. Is that too much?
How would you mount the Wilwood bracket? Would it fasten from above?

More room on LHD thats how

Thanks for the info classicswede. So the 4 pot calipers will bolt onto my steering knuckle, but will I be able to run my stock rotors?





Thanks for the link. At this point I think I'm just going to run rebuilt stock calipers to keep it simple. At some point in the future I'd like to design a completely new front end that uses the steering knuckle from a newer car that can run a big rotor and a nice caliper, along with a custom K-member to run adjustable tubular A-arms and a rack & pinion for steering. That would be a nice upgrade.

I'm also thinking that the Wilwood assembly won't fit when mounted lower down. Most brake design articles I've read say a pedal ratio of 5:1 to 6.5:1 is the ideal range for manual brakes. Any modification of the Wilwood pedal arms would take the ratio to way over 7:1. So yeah I think the custom brake arm is the way I'm going. I'll definitely post plenty of pics and dimensions of it when I get to that point. :)

I ordered some parts yesterday afternoon from Summit Racing Equipment and they arrived this morning! Talk about fast. The master cylinders and the balance bar all seem pretty well made. There are a few product PDFs on their site that show drawings of this balance bar, but none of them give dimensions which is pretty surprising. So I thought it'd be a good idea to post some of the more important dimensions as measured by calipers in case someone needs them as well as a pic of it mostly taken apart to show how it works.

Wilwood 340-1757 Balance Bar Assembly Dimensions
Weld tube OD = 1.251"(31.78mm)
Weld tube ID = 1.009"(25.63mm)
Weld tube length = 1.498"(38.05mm)
Spherical bearing housing OD = 0.997"(25.32mm)
Threaded pivot bar OD = 0.560"(14.22mm)
Threaded pivot bar Length = 0.930"(23.62mm)
Threaded shaft length = 4.870"(123.70mm)



http://i797.photobucket.com/albums/y...ceBarParts.jpg

I am looking at the same balance bar from wilwood and a pair of these compact master cylinders http://www.wilwood.com/Start/PDF/Com...C-Brochure.pdf. I dont have a lot of room because the car is RHD and the injection plenum is in the way.

Is there enough clearance either side of the pedal for the balance bar? If not i was thinking of offsetting the pedal or if i must cut out the side of the pedal pivot box and extend it. What do you think?

What cylinder spacing are you going for ? 2.5"? Is it possible to reduce the threaded shaft length from 4.87" to allow more clearance. I know this would limit the amount of adjustment but would it be a problem?

By the way what did the balance bar cost over there. Here in the Uk it is £46.50, about $77.50.

I dunno if this pedal box would help..cylinders are inside the car..
http://tinyurl.com/ylzjdco

I went with the exact same master cylinders as well. I like how compact they are as well as being anodized black. I paid about $62 for my balance bar and about $80 each for my master cylinders. BTW I just found this nice Tilton balance bar that uses a thicker 7/16"-20 threaded rod. Stronger and cheaper, oh well too late now.

It doesn't look like there's enough clearance to mount the balance bar into the stock arm location due to the firewall. Shortening the threaded shaft will severely limit the amount of bias adjustment and I want to eventually add this accessory so I'm leaving the length alone on mine. I don't want to cut and rebuild the firewall either so I think an offset brake arm is the way to go, as you mentioned. This is the only way I can think of to mount the two master cylinders in the stock area, have the arm clear the steering column, and have the brake pedal in the proper place. I'm going to draw this whole area in Google SketchUp to see how much of an offset will be required.


amazon69,

Thanks for the suggestion, but those types won't work though due to the position of the steering column.

Update: I gave up trying to learn Google SketchUp, it sucks. So I downloaded SolidWorks trial, it's awesome, and I'm slowly playing with it. In the meantime though I've just been making sketches in a notebook of various ideas. I went through about four different designs and finally hit upon something I'm pretty happy with. Input and/or comments on it's design are welcome:

http://i797.photobucket.com/albums/y...etch-Front.jpg

http://i797.photobucket.com/albums/y...ketch-Side.jpg


The scanner picked up a page of notes behind unfortunately. So the main body is 2.5" x 2.5" x 0.120" square tube. The recessed cavity is 2" x 2" x 0.120" square tube. Upper pivot tube is 1" OD x 0.834" ID seamless, middle tube is the 1.25" OD x 1.01" ID that came with the balance bar, and lower tube is of course the steering column. The bottom angle is 2.5" x 2.5" x 0.1875". The brake arm itself is 0.1875" x 1.25" and while not shown in the drawings will be bolted at the top to the assembly and curved toward the seat down by the pedal. This arm will be water jet cut from a cold rolled steel for strength. I ordered most of the materials from onlinemetals.com and received them the other day:

http://i797.photobucket.com/albums/y...m-RawMetal.jpg

I'm going to start on it tomorrow and hopefully get everything cut to size. I don't have access to a mill so I'm going to be doing this the hard way with a drill press, hole saws, angle grinder, hacksaw, etc. I do have a horizontal bandsaw at least which is an absolute must for metal projects. Hopefully once it's all tack welded together it will fit the pedal box the way I'm hoping, guess I'll find out how good my measurements were.

In other news I was directed to local Volvo parts guy who has an 1800 rearend for me and I should be going to go pick it up next week. Also a few days ago I picked up a nice used set of 16" Volvo Hydra wheels which will be a nice upgrade from my rusty steel wheels and worn out tires. :cool:

I'm researching various options for better front rotors and calipers and have a few questions for those more knowledgeable. Does anyone know if the 2 circuit 1800 bearing hub will work on the 1 circuit 122 spindle/steering knuckle? I could just drill my stock hub, but that 1800 hub already has the 5 x 108mm bolt pattern I need.

I'd definitely like to run vented rotors and I'm considering using the 960's 287mm x 22mm rotor. Thing is the 960 uses a single piston slider caliper and I'd much rather use a multi-piston fixed caliper instead. The 240 uses a 4 piston fixed caliper, but it's made for a 263mm rotor. Does anyone know if the 12mm disc radius difference would cause problems?

Do you have an idea what force each caliper will apply? If so torque is force x distance so if you know the applied force by each caliper times that by their respective radius and that will tell you which system has the best breaking force. I assume that is how it's worked out.

I think I may have misunderstood your question. I think you are asking about using a 240 caliper on a 960 rotor?

Yup, ideally I'd like to run the 4 piston 240 caliper on the 960 rotor.

I just found a thread talking about using an aluminum Mazda RX7 Turbo II caliper with 940/960 rotors on a 240: http://forums.turbobricks.com/showthread.php?t=68630

The caliper they're using in the above thread is from the '86 to '91 2nd gen 5 lug turbo or NA Mazda RX7. It's a 4 piston non-staggered bore cast aluminum caliper designed to run with a 276 x 22mm rotor and 15" wheels. So it combined with the 287 x 22mm 740/760/940/960 rotor there is only a 5.5mm radius difference. This is definitely the route I'm going since all the parts are so cheap and will fit inside my new wheels. All I need to do now is fab up an aluminum adapter bracket to hang the caliper. :cool:

I've narrowed it down to three aftermarket 287 x 22mm Volvo rotors:

Brembo BR25287 - $47.75 These look like a simple but high quality vented rotor. Their only interesting attribute is that they're "Made of high carbon cast iron...With better damping factor that reduces noise and vibrations."

Centric CE120.39014 - $42.34 These are interesting because they're a 2 piece floating type rotor for a great price. Of the group these are the ones I'll probably go with. I just wish it was slotted, which brings me to:

ATE W0133-1613244 - $62.95 These have a really nice slot pattern and seem to be overall nice quality. Only problem is that I can't verify what actual size they are and the manufacturers site isn't much help nor is Google. I spent just 40 minutes with a thepartsbin.com agent through their "Live Help" feature only to find out that they don't actually know what size it is and that I should just use the Brembo part above that I gave her as a cross reference... Great, thanks for the help. So I just sent an email to someone at ATE asking if they might be so kind as to give me a part number for the size rotor I need. Considering how lousy their product information support is I'm not very hopeful, I shouldn't have to work this hard to find simple product specs. So again I'm kinda leaning towards the Centric 2 piece.

This is all good stuff. I like your thorough approach and attention to detail. Couple of comments:

I guess you already know that 164E vented discs and 4-pot calipers will bolt straight on to the Amazon? (At least, I've been reliably told they will - not done it personally).

I did a similar brake upgrade to my Scimitar. I converted the rear drums to discs (Rover discs, Ford calipers, home-made brackets) and fitted Wilwood vented discs and calipers. I used twin separate Wilwood master cylinders with a remote adjustable balance bar, all mounted inside the car on a home-made pedal box similar to yours.

It all worked and was worth the effort.

I can also confirm that you don't need a servo (booster). If you calculate the cylinder/piston ratios carefully (taking into account estimates of dynamic weight distribution pedal leverage of course) you will have strong, easy to use brakes with light pedal prsssure and no need for a servo.

Look forward to more updates

Good luck

John

164 discs will not fit. Amazon has discs secured to the back of the hub where the 164's fit over the front and are a different PCD to the amazon.

Hi Dai, whilst we're on the subject of brakes, any sign of the servo I bought from you off ebay some 6 months ago, paid for promptly & am still waiting for!

John,

Thanks for the nice comments. This project has required a pretty large amount of research so far. Volvo used all kinds of disc and caliper combos in the 700 and 900 series and it seems like the most common disc was the 280 x 26mm, which is what the majority of auto part sites sell as "fits all submodels". The single most useful tool I found for making sense of it all was the Brembo Aftermarket Disc Catalog. Looks like the 780 is the only one that didn't come with the 280 x 26mm disc. It came with either the 262 x 22mm or the 287 x 22mm, which is the size I'm after. So this is the model I've been using when looking for rotors online. Also it seems like the various different slider calipers are interchangeable with all the disc sizes, just different mounting brackets are required. However they do have either one or two inlets depending on if the car came with ABS or without, respectively.

I'm glad to hear that the twin master cylinder/balance bar system doesn't need a servo. My estate requires quite a bit of effort for emergency stops as it is now. I'm definitely looking forward to the much greater efficiency and capacity my new brake system will have.





It's been raining the last couple of days here so I didn't do any fabricating until today. I spent about an hour playing with my horizontal bandsaw accurately adjusting it back to 90° from the 45° I was using on my last project and finally got around to replacing the four adjuster screws with shortened SS ones. After that was done I got down to business:

Notch marked out on the main body and first piece cut.
http://i797.photobucket.com/albums/y...FirstPiece.jpg


Corner radius of notch determined and centers punched. I also cut most of the top part of the notch with the horz bandsaw.
http://i797.photobucket.com/albums/y...Arm-Marked.jpg


Notch corners drilled to 3/8".
http://i797.photobucket.com/albums/y...ersDrilled.jpg


Remaining cuts done with jigsaw.
http://i797.photobucket.com/albums/y...hBottomCut.jpg


Skipping ahead a bit, this shows all the parts I made today in an exploded view. They're all shaped and deburred here.
http://i797.photobucket.com/albums/y...lodedParts.jpg


Fit check.
http://i797.photobucket.com/albums/y...m-FitCheck.jpg



Cutting the notch was much easier than I was thinking it would be. The only real PITA was that the square tubes are not really dimensionally accurate. So I had to use the bench grinder to custom mate everything for the flush fit that you see in the last pic. Guess that's to be expected with cheap steel like this.

Update: I've almost completely finished the main body. All that's left to do is fit this into the pedal box of my estate and mark the final position of the upper pivot tube for welding.

First weld, which will be inside when assembled.
http://i797.photobucket.com/albums/y...7/DSC02314.jpg


This is the main body fully welded, grinded flush, and sanded smooth. All the edges were beveled first to give good penetration.
http://i797.photobucket.com/albums/y...7/DSC02340.jpg


This shows the balance bar pivot tube welded in. The other side didn't turn out as good so I'm not going to show it. ;)
http://i797.photobucket.com/albums/y...7/DSC02357.jpg


And finally here's my "new" 1800 rearend before cleanup.
http://i797.photobucket.com/albums/y...7/DSC02335.jpg

Looking good. Are you going to fit bushes or bearings to the pivot or have you machined the body to fit the pivot shaft?

I hope you dont mind but i will be copying your design!

Heres a few pics of my ES back axle with the estate brackets welded on



http://i481.photobucket.com/albums/r...k/P3130104.jpg
http://i481.photobucket.com/albums/r...k/P3130108.jpg
http://i481.photobucket.com/albums/r...k/P6210162.jpg

The upper pivot tube will be welded in and it will use the stock plastic bushings to keep it simple. I appreciate the axle pics, they'll be useful for reference when that step is reached. Got a bit more done this evening:

I thought the body assembly was almost done, but totally forgot that the upper part of the body needed to be cut down around the upper pivot to clear the pedal box. The horizontal bandsaw made short work of this otherwise PITA step.
http://i797.photobucket.com/albums/y...7/DSC02361.jpg

http://i797.photobucket.com/albums/y...7/DSC02364.jpg



This shows the body with both the balance bar and the pivot tube & bushings.
http://i797.photobucket.com/albums/y...7/DSC02377.jpg

I've been super busy this last week so not much progress has happened. My sister's BF was visiting and we built him a sweet custom table that he designed for his old school 9" Southbend metal lathe. Steel pipe 2.5" x 1/4" + forged fittings = lots and lots of grinding and welding compounded by the fact that I got sick half way through. Turned out pretty good though:

http://i797.photobucket.com/albums/y...7/DSC02398.jpg




During all that I did get a chance to tack the upper pivot tube into the arm body. I positioned it so that with the balance bar centered in the arm body there was equal space on either side of the threaded rod. It ended up being about a 1/4" to the clutch arm on the left and a bit less than that to the pedal box wall on the right. I might have to "massage" this wall a bit to give some more clearance or maybe just cut the threaded rod a bit.

http://i797.photobucket.com/albums/y...7/DSC02411.jpg

http://i797.photobucket.com/albums/y...7/DSC02405.jpg

Excellent work; I love the quality of fabrication going on here!

Yes, but it's vital to get the calculations right. There is a good guide, on the Wilwood site I think. (If it's not there, come back to me and I'll try to find it.)

Cheers

John

Why are you putting in an 1800 rear end? The axle needs modification to fit the 120 wagon rear suspension. The 240 axle has a far superior handbrake mechanism and is the right width, still needs modification of course.

Derek;

I normally don't chime in unless I have some useful (or useless depending on your disposition) information to add to a thread...(or even the odd wisea** comment), but I have been following this thread from the beginning and am compelled to comment that you do beautiful work!...I think we could enjoy an adult beverage together!

I look forward to continuous project updates, pix, and hopefully a comprehensive wrapup when complete.

Cheers from the other coast!

Thank you guys for the nice comments. I take great pride in my work and I truly enjoy working with my hands. Not only that but once we're gone from this world the things we've built will be the only things physically left of us so I build accordingly. Also I feel our country is over run with cheap Chinese garbage everywhere I turn, so it really feels great to be able to build anything I need out of quality materials while avoiding buying said garbage as much as possible. There was a time when most everyone knew how to work on their own cars, built things with quality materials, and generally took pride in using high quality American made goods. That seems to have changed into trade your plastic car in every two years, rebuild every 5 years with disposable materials, outsource everything, and generally use the cheapest crap possible as much as possible. Even though I'm only 27 I feel like an old-timer in my ways!

Ron, beverages of the adult variety are one of my favorites and if you're ever in the SF area feel free to hit me up and we shall partaketh. http://media.bigoo.ws/content/smile/party/party_7.gif


940_Turbo, using an 1800 rear end seemed logical as that's what everyone uses in this application and it's a good axle (Dana 30). I could of swore reading that the 240 rear was a bit wider but I haven't actually measured one to verify. I couldn't find any good pics to show the difference, care to elaborate on the handbrake?



Got the pivot tube fully welded in yesterday and redid the hard to reach inside balance bar pivot tube welds:

http://i797.photobucket.com/albums/y...7/DSC02419.jpg

So I've talked to a few people and also read that the later 5 x 108mm 2 circuit 1800 hubs should indeed fit on the Amazon spindle. Ideally I'd trade my used Amazon hubs for a used pair of later 1800 hubs, I'm looking into this with my local parts guys. This would be preferable from a strength standpoint compared to drilling five more holes in my stock hubs. Anyone have a pair of 1800 hubs they'd like to part with? :)