Hello everybody. A while back, I saw a post that mentioned something about converting the drum brakes on a PV544 to disc brakes. I have spent three hours looking for the post and have turned up nothing. Can anybody help me out in reguards to going about converting drum brakes to disc brakes? I have to turn my PV544 into a daily driver and I've had a countless number of religious experiences with the drums. Mainy because they fail when going downhill (and believe me, that's happened TWICE! Not a fun experience!!)

Raymond

A couple of things...

Listen to Leonard: Don't Do It.

Unless of course, you just like to screw around, in which case , lemee tell ya how to make it into a dual system...

There's no reliability increase in switching to disks; if the system isn't well maintained, it will fail, regardless. In the process of changing all the brake lines on my wife's '57 444, I bent the long front to rear line to put it in the garbage can, and it snapped in half. Whew!!

ALL the lines, calipers, and cylinders are readily available and should be replaced or rebuilt.

If you want to get really fancy(recommended), John Farrell Auto Parts(800-454-7977) sells stainless pistons for 122/1800 caipers(they're the same from 6-1-64 to 8-1-68). Of course, these are E-Jag parts, but what the heck?

No 544 came from the factory with disk brakes, though I've seen stock backing plates with both 544 and 122/1800 bolt patterns.

Amazon and 544 rear brakes are the same; many Amazons came with IDENTICAL Wagner brakes; you certainly don't want Girlings.

There are 2(or more) interchangeable cylinders for the Wagner rear brakes; 7/8", and 3/4" bore; smaller is better in conjunction with front disks. My first 544 came with one 3/4 and one 7/8 on the rear. Try to figure THAT one out.

Use a Wilwood or Ford SVO adjustable proportioning valve from your local speed shop, Summit Racing, Jeg's or the Ford dealer. The 122/1800 ones are pretty wasted by now and aren't worth rebuilding unless you're a purist.

No 544 came from the factory with disk brakes, though I've seen stock

> backing plates with both 544 and 122/1800 bolt patterns.

> Amazon and 544 rear brakes are the same; many Amazons came with

> IDENTICAL Wagner brakes; you certainly don't want Girlings.

Actually the Wagner rear brakes on an Amazon are only used on the non servoed dual circuit North America spec 1968 Amazon, or very early Amazons with drums all round. No other version was ever fitted with them.

European spec cars always used a version of the Girling rear brakes, the very late Dual circuit cars being fitted with a self adjuster. My own experience is that the Girling is more effective at giving properly balanced front/rear braking bias than retaining the Wagner brakes at the rear, especially if you fit an in-line servo.

Up to a point I agree that a well maintained drum system is better. It does however require more skill than the disk/girling setup to get balanced nicely. During normal use it feels more positive than the Disk brake setup. For really hard use though, especially if you take the car into mountainous terrain the brake fade can get a bit TOO interesting.

How did you Dual Circuit a PV?

Regards

I've pulled several sets of Wagner brakes from Amazons at the pick-n-pull; while I know very little about year-to-year variations, the Wagners would seem over represented.

I definitely agree the Girlings are less effective than Wagners, but a good proportioning valve solves that problem. Girlings are also a maintenance nightmare, and parts availability (at least where I am, In California), is much worse. Even here, the adjusters freeze.

My disk setup (with Wagners) is VERY nice; I drive in mountainous terrain regularly.

I still think it's only worth it if you like to fiddle.

Did I mention my 445 with 10"F/9"R drums from an Amazon Wagon?

I split the circuits F/R using a Mazda 626 m/c which conveniently has a remote reservior (I T-ed the stock one). One of the nicer features is that the bore is 7/8", instead of 1", so the pedal feels much better, still without excessive travel.

I drilled and tapped the end of the Mazda part to take a stock 1/8" pipe brakelight switch. I made a stout bracket which bolts in the stock location and uses the stock linkage. I do have AutoCAD files of the bracket, if anyone's interested.

There is a detailed description as well on the vclassics.com page.

It is a pretty straight-forward job as Pete says. I am almost dead positive that none of the PV's ever had disc brakes. Having "been there, done that", I would offer up a bit of my experience. Unless you have the time and the money and the know how to do the conversion, rebuild and replace the shoe set up. They will and do work very well. For most of us in daily drivers, we will never tax the drums to the point they let us down. If you have brake failures, it almost assuredly is the master cylinder for you to loose them "all" at once. Even with the disc set up, if you loose the master, you still loose all the brakes. All of the parts are readily available and are substantially less expensive than converting to discs.

I am putting together my 544 for my daughter, and I am staying with the drums on her car. I have discs on all four corners of my 444 and honestly, there isn't much difference. You are welcome to email me direct if you would like some pictures and such. Keep in mind I am just a "good ole boy with a really red neck" that just happens to like to tinker on things and what I have done may not be what you or anyone should or shouldn't do.

Leonard

Great post by Peter. I understand there were a few 1966 PV544s sold in the US by Volvo, and I have heard these cars had disc brakes. I doubt the parts are still available, but a dealer parts book might be of some help.

The drum brakes on the PV544 were the same as used on some Studabakers and Ramblers, both which were substantially heavier than the PV544. I found the brakes to be very adequate compared to others cars at the time, but I never had a failure. PV544 drum brake parts and shock have been quite difficult to source for some time, so the disc brake conversion along with a shock update would be great.

What you need to do is find a 120 series Volvo and steal its brakes.

You need the front brake disks and hubs, the caliper brakets, and the calipers themselves.

The front wheel bearings are identical between 120 and PV so the disks and hubs will fit straight onto the PV stub axle.

There are three main ways of doing this. The most common way is to install the disks in the same orientation as they were fitted to the 120. You need to re-drill the caliper bracket because the mounting holes differ. Normal practice is to swap the mounting brackets from side to side, ie you use the left 120 bracket on the right of the PV. Everything else stays where it was.

The problem is that the caliper now occupies the space where the shock absorber is. You can "solve" this by taking the shock mounting bracket out of the upper wishbone and upright and refitting them so they now face forward. The drawback to this is that the bottom mount of the shock interferes with the steering arm on full lock, restricting your turning circle. Lots of people run like this.

Leonard who frequents this board installed his disks as above but got round the interference problem by re-locating his shock absorbers.

I chose to go a different route. I get the holes in the caliper bracket welded up and weld two ears onto it. I then mount the calipers at the front, meaning the shocks can stay where they were, I can send you some pictures if you are interested.

I would also swap the rear brakes to Amazon spec. These bolt straight on, also use the limiting valve to the rear brakes from an Amazon.

Regards

Just a quick caution ... if you are going to install 120 disk brakes on your 544 .... the PRE '66 brakes are different than the '66 and up ... Parts for the '63 to '65 brakes are no longer available so I suggest you try to obtain a '66 or newer set. I ended up having the calipers on my '65 rebuilt .. had to replace the pistons and none were available until my mechanic found a set of CHRYSLER manufactured calipers that had the same size pistons .... and don't ask me what modle they are off because he did not share that secret with me ... I believe that the '66 and up brakes are GIRLING but have no idea what the early ones are.