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Sun Jan 15, 2012 10:35 am

No problem Ray! I get snippy myself. :twisted: I think I really should have said the search for Cheap parts/solutions is what bothers me. I'm as broke as the next guy, but I still just dig deep and buy the 'expensive' part I want/need Now! I won't waste months looking for a good deal. $50-$250 still seems cheap in comparison to new car part prices.

Sun Jan 15, 2012 8:28 pm

I just took out the under dash mount for the pedals and the master cylinder i need to repaint it anyway its rusted up pretty well. I have a new master cylinder from a 1969 beetle that I intend on building a mount for.

Sun Jan 15, 2012 10:10 pm

Remember to take pics of the process! :D (and do your homework if you havent allready made sure the bore size will work)

Sun Jan 15, 2012 10:19 pm

Its slightly larger than the stock 411 master cylinder.

Mon Jan 16, 2012 5:36 pm

Hamsterben wrote: I just took out the under dash mount for the pedals and the master cylinder i need to repaint it anyway its rusted up pretty well. I have a new master cylinder from a 1969 beetle that I intend on building a mount for.

I did that in about 2000. There were a lot of headaches. I'll list a few in hopes that you can avois some pitfalls.....but this is not a really good solution.

(1) Whatever maste cylinder you select must deliver the correct amount of fluid to each circuit. My first assumptions that just finding a cylinder with the same bore and stroke length on each circuit would solve that issue were not correct. I had to adjust the length of the stop pin on the bottom of the inner and outer piston.

The reason for this is that the stroke volume s not just set by apparent stroke length. As the outer piston starts moving from the pedal pushrod....the second piston does not exactly start moving at the same time. A compression point must be reached on the first piston before the second one begins moving at the correct rate. It caused a horrible lag that made the car almost undriveable.

Grinding the stop pins under each spring to bring the exact fluid volume to the correct levels....caused a recalibration need for the spring tension. At one point early on it resulted in a broken spring. I eventually used springs from my 412...which took a bit of doing and were never perfect.

So why did I put up with this and not just choose another cylinder from a bug or type 3?

(2) Because said cylinder also needs to physically have all of the tube connections and switch connection ports and on teh correct side....and at the correct angle.

(3) why the correct angle? Because you also need to find room and space for the mounting ears. To get this one to work....I think it was a super beetle cylinder.....I had to (a) weld in a plate with the center hole and studs to meet up with the ears to teh cylinder...and to get the cylinder close enough to the pedal cluster to meet up with the line of teh pushrod....a slot had to be cut in the side of the pedal cluster for the inner ear to reach through so the body of the cylnder could fit flush....or close to it....against the pedal cluster.

(4) all of this has to fit within the right fore and aft spacing relative to the pushrod and pedal stops....and thats not easy. The type 4 cylinder is remarably compact.

This is by no means and easy modification. And....its no guarantee that another make of cylinder will fit when it comes time to change it (i.e mine was set up to take an ATE cylinder...and it took some grinding to even think about putting a Varga in there.

This is where I left it when I parked the car. that system is still in there. I started doing the in-trunk mods for the bus cylinder at that point.

Ray

Mon Jan 16, 2012 6:35 pm

Ebay has the Cardone rebuilds for sale. Are those worth a gamble?

Mon Jan 16, 2012 10:10 pm

I want to mount a master cylinder under the dash and I can build a mount for it. What master cylinder should i use? Or what if i do a rear disc conversion from a Porsche 914 I already have the front calipers switched to 914 ones and use a 911 master cylinder.

Tue Jan 17, 2012 9:24 am

in the link i posted that person used a 914 cylinder.

Tue Jan 17, 2012 11:25 am

I think i may go with the bug master cylinder and an adjustable mount so I can install different master cylinders when I need to switch them out. If it wont stop the car ill use one off a 914 or 911.

Sat Jan 21, 2012 10:36 am

Hamsterben wrote: I think i may go with the bug master cylinder and an adjustable mount so I can install different master cylinders when I need to switch them out. If it wont stop the car ill use one off a 914 or 911.

There are "0" benefit to using the Porsche cylinders. There is no performance increase ...just a cost increase. Also some of the Porsche cylinders are 17mm...which will not operate your brakes.

There is no difference between Porsche front calipers and 411/412 calipers. Same parts, same manufacturer. The pre-72 411 and 914 used the same rotors and calipers. The August 72 and on 412 and 914 used the same rotor and caliper. Just be sure you know this so that no one is trying to sell you something standard at a higher price.

The rear 914 caliper was barely adequate for the 914. It is undersized for the type 4 and expensive to find parts for.

Since the type 3 and type 4 cars used the same rear drum, backing plate, hardware and shoes...slightly different bearing covers and different stub configuration with same spacing....you should find a decent type 3 kit with iron caliper bracckets and install a modern sliding caliper.

All around, cheaper , easier and better braking.

Its a nice thought that you want to keep an underdash cylinder...though I don't know why. To each their own. Keeping the cylinder under the dash greatly limits your choices for cylinder. The type 4 cylinder is unique...because it had to be just to fit under the dash. If this is your route...just have the original sleeved or do a basic rebuild.

No matter what you choose, the master cylinder must have exact volumes...or larger volumes than stock....and the same piston stroke timing (meaning same spring starting points). Either way you will need to install an aftermarket brake proportioning valve in place of the ones that the two and four door sedans have. Wagons should have one added. I have no idea whay they deleted the proportioning valve on teh wagons. they needed it.

Even when these cars were still 10 years old...I found few stock proportioning valves that still worked. About 1% probably still work now. Kits are unobtanium.

I used to have kits made in the mid 90's. They worked well, but typcially I went through 5 seals rebuilding them due to installation issues. Better to buy new adjustable units. Many brands to choose from out there and more compact, cheap and easy.

You will find out the problems when you start trying to build a bracket and install other cylinders. I went through at least one and a half dozen cylinders from both air and water cooled cars. The few I found that could fit.....were not volumetrically suited. Ray

Sat Jan 21, 2012 11:32 pm

I get Porsche parts cheaper than vw parts. I have a friend who deals in Porsche parts and i can work off whatever I need.

Sun Jan 22, 2012 10:18 am

Thats a good reason. On the other hand....make sure that its a 19mm cylinder and that it runs the same volume or more for the rear brake circuit.

Its going to be difficult fitting this under the dash. The easiest non-stock cylinder fitment would be a vanagon master cylinder and a simple piece of angle iron. That is easily done with the vanagon clutch master cylinder in place of the 411/412 clutch master cylinder. I believe the brake master cylinder mounts the same way and is largely the ame stroke and volume.

Take a look at the vanagon cylinder before you start cutting and welding. The lightbulb should light up when you see it. Ray

Sun Jan 22, 2012 11:35 am

would a bus master cylinder work for this like this one?

http://www.chircoestore.com/catalog/product_info.php?cPath=86_87_88&products_id=600

Sun Jan 22, 2012 3:30 pm

No...sorry it will not. I tried that already. It in fact would be the least able to fit of almost all VW cylinders.

So you can get an idea of the whys and why nots I'll list them.

(1) 411/412 master cylinders are quite slim. They are thin walled and slightly offset to the right. They fit flat on the right hand side vertical wall of the pedal cluster. The offset aligns the centerline of the piston with the pushrod exactly.

(2) 411/412 cylinders do not have the two bolts "ears at the pushrod end. They have a cast on pad that takes two 12 or 13mm bolts perpendicular to the bore....which I'm sure you already know.

(3) Even if it were the same bolt configuration, the bus cylinder is 3mm larger in diameter overall. Even without mounting issues it puts the pushrod out ofalignmet by a minimum 1.5mm...which is a problem that requires making a new hardened clevis pin for the pushrod...finding an offset version of the rather unique pedal return spring and a few other small mods.....which are very hard to fit.

(4) Its too long to safely fit without work that may cause electrical issues under the dash....but this is not an overriding issue.

(5) Notice in teh picture of the bus master cylinder in that ad....thatthe fluid ports are on top (good) the switch and pressure ports on the right (good) but.... the ears are dead 90* out from the fluid ports which need to be striaght up on top. This means that putting the cylinder against the pedal cluster wall where the original was....and welding a flange on to bolt the cylinder to...will mean that the left hand bolt hole of the master cylinder flange will either have to be ground off (not doable due to not enough metal holding the cylinder down)
.....or a slot drilled through the vertical side wall of the pedal cluster for the left hand tab to slip through. A tab on the inisde of the pedal cluster will have to be welded to bolt onto the MC tab for strength...and there is no room to do this because of the other stuff inside of there.

(6) if you look at some of the super beetle and 80's rabbit MC's...you will see that their maounting flanges are at an angle....not a perrfect one...but much more conducive to mounting alongside the pedal cluster.

The way I mounted a super beetle MC in mine was that I took an old 411 MC and cut away all but the mounting tabs and the c;luster side of the bore. It was just a pad at that point. I ground it flat and shaped it until it held the super MC flat and parallel to the pedalcluster. I used a steel clamp to clamp the MC to the pad....along with grinding off the inboard MC mounting ear and welding on a tab that bolts to the remaining outboard MC mounting ear.
Not perfect...but stable and solid. However...the mastercylinder internal configuration was less than desired and not as good as stock in performance.

However Having a bus core on hand though is what led me to putting it in the trunk. Having a 22mm master cylinder would give superior braking and pedal feel.....and would have the extra capacity for brake mods at the wheels. Ray

Sat Feb 04, 2012 10:42 pm

ALLWAGONS wrote: The one I got from them didn't work. I'll have to return it. Back to square one. Who rebuilds them?

I stand corrected, after the install, I drove it having to pump several times to build enough pressure to brake. I re-bled it and now it works perfect. BTW I found quite a few NOS one in my desperate search for a MC.

Sun Feb 05, 2012 12:51 pm

This is actually fairly normal for 411/412's. They have a rather circuitous brake system. They generally take several bleeding sessions over a couple of days with driving in between.

I forgot to mention in asnwer to Reluctantartists question....yes...A1 Cardone have generally been one of the very best makes in rebuilt parts. Ray

Fri Mar 23, 2012 8:54 am

I am happy to report that my A1 Cardone, MC is still working just fine. For those that have doubts. Life is better when you can drive your VW..... and stop your VW.

Fri Mar 23, 2012 11:53 am

ALLWAGONS wrote: I am happy to report that my A1 Cardone, MC is still working just fine. For those that have doubts. Life is better when you can drive your VW..... and stop your VW.

And life is longer too no doubt! Good to hear. Yes...A1 Cardone has been around for ages. They probably reman parts in many of the same places or countries as others....but it seems their quality control or choices of parts quality, packaging, instructions etc....are better. Ray