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Mon Sep 03, 2007 2:20 pm

I just finished one side of the caliper upgrade on my 1970 Squareback. The caliper was sticking, since I had to take it off anyway I figured it wouldn't be much more work to do an upgrade. It's basically a bolt on upgrade, unless you have the early calipers instead of the later ones, then it requires changing the spindles.

There are a few 914 sites out there with details on swapping over to BMW 320i calipers. Since the later type 3's used the same calipers as the 914, I figured I would try it and see if it works. The backing plate needs to be trimmed a little to get them too fit. I also used the old locking plate for the caliper bolts as a shim to center the caliper over the rotor. With the Type 3 wheels there is a small amount of interference that a file took care of. I think if I would've went with a slightly thicker shim there would have been no interference.

I can't give any driving impressions yet, as I only have the one side done. Maybe I'll get it done next weekend, since I have the early calipers, so it requires changing the spindles as well.

Mon Sep 03, 2007 2:51 pm

what did those calipers run you? $$$$

Mon Sep 03, 2007 11:11 pm

What piston size do they have?

Tue Sep 04, 2007 6:47 am

The calipers are rebuilt units that I got from partsamerica.com for $28 each plus a $10 core charge. They are for a 1978-1983 BMW 320i.

The pistons are bigger, but I'm not sure of the exact size. The brake pads are also larger.

Tue Sep 04, 2007 6:50 am

Great info

Can't wait to hear how it improves your braking.

good luck

Wed Sep 05, 2007 10:50 am

Will this upgrade work on a '69 Square?

Wed Sep 05, 2007 11:45 am

It will work on a 1969, but will need the spindles changed over to the later model ones. I believe the change was in 1972.

Wed Sep 05, 2007 2:37 pm

hmm now to dig up some 72-73 spindles........ wish someone had a set in reno!

Thu Sep 06, 2007 10:39 am

Thanks for the info! I wasn't sure when the changeover was. Need to keep an eye out for some new spindles now. :)

What is the difference between the two spindles? I would assume there is no differences in mounting.

Thu Sep 06, 2007 11:23 am

gtixpress wrote: Thanks for the info! I wasn't sure when the changeover was. Need to keep an eye out for some new spindles now. :)

What is the difference between the two spindles? I would assume there is no differences in mounting.

The spindles are a direct swap. The diference is in the caliper mounting hole spacing.
66 - mid '72 have about a 2 1/4" spacing between the caliper mounting bolts.
Mid '72 -> have about a 3" spacing.

Thu Apr 24, 2008 11:04 am

Just curious if this upgrade was ever completed and how well it worked out?

Sun Sep 27, 2020 1:25 am

Me too !

I found a set of late spindles and Calipers , if this setup works fine I’m considering to do the same in place of rebuilding the old calipers

Sun Sep 27, 2020 7:55 am

spaardingske wrote: Me too !

I found a set of late spindles and Calipers , if this setup works fine I’m considering to do the same in place of rebuilding the old calipers

Rebuild your old calipers. Its just not that hard. And...high quality kits are available for cheap and so is hardware.

There are good NEW BUILD calipers with new castings available.....like Centric. However for the past five years plus.....virtually all of the usual suspects for rebuilds/remans out there from places like Cardone......are less than good quality.

The other problem with the rebuilds is that many of them are rebuilt cores that needed more hand work than a reman shop was willing to invest....so they get oversize bored, new pistona nad seals......all of which only work with seal and piston kits sourced from the rebuilder....who does not sell parts. So going forward....any issues means replacment and not rebuild.

Ray

Sun Sep 27, 2020 10:46 am

I'm not at all sold on the need for brake "upgrades" on our cars. I like the idea of the 5 lug disc upgrade on earlier cars because drum to disc really IS an upgrade, and original parts are hard to find, but other than that the only thing you'll gain is bragging rights.

I have a very good M-B and 911/912 repeat customer in Asia who was having a big huge restoration shop in Clark Freeport Zone do all his cars, but there were several issues with his 1969 911T he couldn't get right. That firm collapsed and was seized by the government for tax hyjinks so my friend decided to start his own shop mainly for his cars with some techs from his company motorpool and asked me to be the remote "shop foreskin".

Anyway, I sent a new ATe master cylinder and caliper kits over, along with pads and stainless flex lines to fix a persistent spongy pedal issue (one caliper piston intermittently sticking). It worked out great and he was super pleased with the brakes.

Along the way I hooked him up with a bunch of suspension tweaks recommended by Chuck from Elephant Racing. He really enjoyed ripping up the track and rallying his car. He said it outperformed all others in his Porsche club.

Anyways, he got an absolutely insane offer from one of the guys in the club and sold the car to help fund his dream 1973 911S I found for him in NYC after years of looking for this exact color/ interior combo in a Coupe. He was working up a prospectus on the T car for the buyer that he asked me to review. I was surprised to see that he noted the brakes had been "upgraded" to 911S vented rotors and M calipers. I asked him when this happened, and he told me it happened back when the "hotdog" shop was working on his car.

He was shocked shitless to find out that all the parts I sent were for the standard 911T bare bones solid rotor system that he had based on the photos from his guys. He was actually more shocked that the stock brakes were more than adequate for his heavily upgraded T than he was shocked that the other guys sold him a bill of goods.

Oh, the car was also upgraded with a 2.7 S engine, Euro cams, PMOs, and 123 ignition instead of the original carbureted low compression U.S. spec 2.0 T.

Germans tend to engineer braking systems looking to the future and taking into consideration possible power and performance upgrades so you don't have to.

Just sayin' is all. If you want to spend your money where it counts, almost always the braking system ain't your candidate beyond making sure it's up to snuff. :wink:

Sun Sep 27, 2020 11:22 am

Tram wrote: I'm not at all sold on the need for brake "upgrades" on our cars. I like the idea of the 5 lug disc upgrade on earlier cars because drum to disc really IS an upgrade, and original parts are hard to find, but other than that the only thing you'll gain is bragging rights.

I have a very good M-B and 911/912 repeat customer in Asia who was having a big huge restoration shop in Clark Freeport Zone do all his cars, but there were several issues with his 1969 911T he couldn't get right. That firm collapsed and was seized by the government for tax hyjinks so my friend decided to start his own shop mainly for his cars with some techs from his company motorpool and asked me to be the remote "shop foreskin".

Anyway, I sent a new ATe master cylinder and caliper kits over, along with pads and stainless flex lines to fix a persistent spongy pedal issue (one caliper piston intermittently sticking). It worked out great and he was super pleased with the brakes.

Along the way I hooked him up with a bunch of suspension tweaks recommended by Chuck from Elephant Racing. He really enjoyed ripping up the track and rallying his car. He said it outperformed all others in his Porsche club.

Anyways, he got an absolutely insane offer from one of the guys in the club and sold the car to help fund his dream 1973 911S I found for him in NYC after years of looking for this exact color/ interior combo in a Coupe. He was working up a prospectus on the T car for the buyer that he asked me to review. I was surprised to see that he noted the brakes had been "upgraded" to 911S vented rotors and M calipers. I asked him when this happened, and he told me it happened back when the "hotdog" shop was working on his car.

He was shocked shitless to find out that all the parts I sent were for the standard 911T bare bones solid rotor system that he had based on the photos from his guys. He was actually more shocked that the stock brakes were more than adequate for his heavily upgraded T than he was shocked that the other guys sold him a bill of goods.

Oh, the car was also upgraded with a 2.7 S engine, Euro cams, PMOs, and 123 ignition instead of the original carbureted low compression U.S. spec 2.0 T.

Germans tend to engineer braking systems looking to the future and taking into consideration possible power and performance upgrades so you don't have to.

Just sayin' is all. If you want to spend your money where it counts, almost always the braking system ain't your candidate beyond making sure it's up to snuff. :wink:

For a type 3 or type 4 car....for the street....I totally agree. Especially caliper wise.

The late type 3 caliper (which is the early type 4 and 914 caliper)...is more than either of those cars need unless you are "tracking" it...and even then there are things you can improve with the original hardware.

The first upgrade....if you even NEED an upgrade on a type 3 with the stock calipers...is a quality rebuild with original castings.

For the most part...for late type 3/early type 4/914 calipers...you can buy original quality kits (with caliper half/bridge seals)...from PMB performance.
For $17 a caliper kit...thats damn hard to beat.

https://www.pmbperformance.com/catalog/item/1925563/4747234.htm

Notice it even comes with new bolts and zinc chromated safety tab locks

You can get Centric kits ...sometimes....from Rockauto. The Centric kits have proven to be re-packaged FAG rebuild kits for ATE calipers....made in Germany....at least for late type 3.
Right now...today...Rockauto is only listing Dorman parts and are out of stock anyway.

2nd upgrade....if you have early calipers and can get spindles and rotors and calipers...upgrade to the later caliper. Thicker pad and rotor and stiff rotor and does not need the early style caliper with the guide pins inside.

You can get EXCELLENT rotors from either PMB or Autohaus AZ.

https://www.pmbperformance.com/catalog/item/1925563/1475445.htm

https://www.autohausaz.com/porsche-auto-parts/porsche-914-rotors-replacement.html

Both carry Sebro...made in Germany and excellent quality and sometimes Autohaus carries Zimmerman....also "generally" made in Germany still and of equal quality to Sebro.

3rd upgrade.....get a better brake pad.
If you drive street or daily and drive aggressively enough to need brake upgrades.... at all.....I could recommend something like the Porterfield RS-4....which is what most of the 914 street crowd really like. I have used them on water cooled Golf and Jetta and they are basically a 15-20% upgrade over stock and are rotor friendly. Great pads.
I have a set I bought for my 412 waiting to be installed.

https://www.pmbperformance.com/catalog/item/1925563/6732628.htm

This is the pad that fits late type 3/early type 4. Read the blurb on the PMB page. They are spot on. If you ever "THOUGHT" you needed a brake upgrade....before changing anything else...change to THIS pad. You may need nothing else at all.

So to this point...outside of a better brake fluid (maybe)....my point is the same as Trams....nothing MECHANICAL really needs to be changed on the type 3/4 FRONT braking system for anything other than serious track use.

Now the rear brakes...different story. The rear drums are quite effectively sized and well built. S if they are in good shape...you could get some better shoe material (at one time I was buying a Mintex shoe which was two steps up just like a better pad).

However....good drums are scarce. And...if you are working the brakes hard or driving high miles and lots of stop and go.....to get REALLY effective rear type 3/ type 4 brakes (they are the exact same rear brakes down to the last part number on the 411/412)....I found that adjusting needed to be done about every 10 days to two weeks maximum.

Bearing in mind.....that I was driving my 412 for several years ...about 1200 miles a week in 70 mph city driving Dallas. Lots of high speed brake jabs and stop and go...so your results may vary. But even when certain weeks were only 500-700 miles....it was still once every 4-5 weeks between shoe adjustments on average.

So.....if you MUST do a mechanical upgrade...after upgrading to late type 3, a clan rebuild of what you have and better front pads....look for a quality rear disc brake kit. Leave the fronts alone. Ray

Sun Sep 27, 2020 4:10 pm

I agree with Tram, a front drum to disc conversion is worth doing. Having done so on my 64 T-34, the brakes were excellent, and I had gone 1 step further by going to a dual circuit master cylinder arrangement.
Back when I built my 65 Notch, I used the early style caliper stock type 3 disc brake set up. One of the biggest changes I made (after driving it for 4 years), was going to wider tires on all 4 corners. I found that the narrow tire (stock sized 165) left a lot to be desired in hard braking and cornering at freeway speeds (a trip thru Pennsylvania proved that to me). Upgrading to 195 and 205 widths made a huge difference in how the car drove, and stopped. A well worth it improvement, and something everyone thinking about going to a "bigger or better" brake set up should keep in mind. Having great brakes with narrow tires doesn't really work, as you're locking up the tires. Just something to think about.

Mon Sep 28, 2020 4:38 am

I drove the original small calipers for several years ( also as a daily driver )with no issues at all . Never had the feeling they were underpowered and needed an upgrade .

But after stripping a 73 fastback for parts , I had the Late spindles and bigger calipers , so that’s where I start to think of a brake upgrade .

After reading al of this I’ll just use the late spindels with rebuild stock late calipers .

Maybe the the brake pad upgrade as suggested!

Discs in the rear isn’t an option as it won’t pass technical inspection over here in belgium . ( don’t want to swap the brake’s every year)

I already have 195 and 205 widths but will change to a smaller size in the front soon as the tires rubbing the fender

Thanks for the great advice!!

Mon Sep 28, 2020 6:30 am

spaardingske wrote: I drove the original small calipers for several years ( also as a daily driver )with no issues at all . Never had the feeling they were underpowered and needed an upgrade .

But after stripping a 73 fastback for parts , I had the Late spindles and bigger calipers , so that’s where I start to think of a brake upgrade .

After reading al of this I’ll just use the late spindels with rebuild stock late calipers .

Maybe the the brake pad upgrade as suggested!

Discs in the rear isn’t an option as it won’t pass technical inspection over here in belgium . ( don’t want to swap the brake’s every year)

I already have 195 and 205 widths but will change to a smaller size in the front soon as the tires rubbing the fender

Thanks for the great advice!!

Since you have stripped a '73.....YOU... probably understand now that the difference between the calipers and rotors that went up to August of 1972 and those that went FROM August of 1972 (1973 model year)......were less of a performance change and more of a longevity change. I am just mentioning it for those who might not know.

The early and later calipers....functionally.....are the same. They have the same piston diameter and the pads....if you put them face to face....have virtually identical contact area.....but the later pad is thicker. So it lasts longer and can "possibly" absorb a little more heat

The difference in the rotor is that the early rotor was slightly thinner. The later rotor.....has a raised ring in the center that fits into the stock wheel. While it makes the wheel far easier to install......thats not really the main function of that ring.

Its function along with a thicker rotor and thicker tire mounting face is to make the rotor stiffer. The earlier rotor had an issue with flexing when you were braking through hard corners.
What this did was flex the rotor out of plane to the brake pads and pistons. This had a habit of cocking the pistons slightly in the bore....and pusuing them away from the rotor on one edge. The only real negative effect this has on braking is that it can cause the piston to excessively retract when you let off the brake while the rotor is flexing.

This makes the next stab at the brake feel slightly odd or longer in stroke as the piston needs to reset itself to normal wimdage gap.

To counteract that....the early calipers had the locating pin inside the bore with the spring clutch or chuck in the back of each piston to keep it locked in position when it cocked.

The other good reason to switch from early to late calipers....is that the early calipers are harder to clean up and rebuild with the pin in the way....although iirc.....the pin unscrews. ....but its getting very hard to find early calipers that st8ll have the pin, still have pistons w8th functional chucks in them.....and most new builds do not have the pin assembly.

Its also probable that the later heagier, thicker rotors handle a little more heat without warping. Ray

Mon Sep 28, 2020 7:33 am

https://www.thesamba.com/vw/classifieds/detail.php?id=2402103

Just to add to the mix...

Mon Sep 28, 2020 11:34 am

Ray, Thanks for letting us know the 2nd function of the centering ring is for. The rotors on my 65 Notch have the centering ring too (early style).