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I am looking into converting my rear drums into disks. Does anyone happen to have a set of rear disks, calipers and all the associated hardware that they'd be willing to part with?

Also, has anyone done this conversion? Any advice?
 

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But Mad North-Northwest
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Also, has anyone done this conversion? Any advice?
Depends on what you're trying to accomplish. I can tell you that on the Giulia I could barely tell the difference between the original drums and the discs on the FRONT. So if you're looking for performance there's d-mn near nothing to be gained by going to discs on the rear.

In my case it was going to cost me nearly as much to get the front drums and pistons redone properly, so the disc conversion started making sense. So there might be good reasons to do it, but performance or brake feel aren't some of them.
 

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Push hard and live
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My best guess is that you could find a rotting 2600 coupe, buy it for parts, and rob the entire rear axle assembly. Plus, you'd have a lot of other parts left over.
 

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I'm both with Gubi and Don on this one: Not much difference in performance and too much hassle trying to locate individual parts. In fact, disc brakes on the rear axle may be harder to maintain because of the parking brake.
 

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When I got my '62 2600 Spider in 1971, it had been converted to rear disc brakes and 15" Borrani wire wheels. The brake conversion was probably necessary to accommodate the disc brakes, as the large drums would not fit inside the 15" wheels. Of course, the front already had disc brakes. What I did not know, was that there was no hand brake parts inside the rear disc "hats" (the small drum cast into the discs to accommodate the drum type hand brake). Therefore, there was NO hand brake. Someone had drilled holes in the outboard disc brake pad of each rear brake and attached the hand brake cables there. When the hand brake was set, it pulled the pads against the discs which just warped the discs and was totally ineffectual. In fact, I could set the hand brake and still move the car by pushing it all by myself! This caused a problem when I had to take the car through the state of Florida vehicle inspection. One of the tests was to check how well the parking brake (hand brake) would hold the car. With the engine idling, I had to set the hand brake and then put the car in first gear and let out the clutch. If this killed the engine, you passed. Since setting the hand brake actually did nothing, I had to devise a solution. Now, the Alfa has a five-speed transmission which, at that time, I was sure no one at the inspection station had ever seen. I tested my technique and went through the inspection. When told to put the transmission in first gear, I put it in FIFTH gear and the gear lever was in the forward position like the first gear of a four speed. The inspector said "let out the clutch" and I popped the clutch. The car lurched slightly forward and died. PASSED.

By the way, the hand brake diameter on the Alfa is 7", which is large compared to other cars. My 69 Porsche has 5" hand brake drums. I discovered that the rear brakes of a Triumph 7 (front discs, rear drums) had 7" rear drums. I converted the Triumph brake shoes and backing plate to fit inside my Alfa " hats" and that is what I still have. They are not as good as the Porsche system but far better than our 2002 Subaru Forester.

When I did this Alfa brake work in the early '70s, there was no internet, no eBay, etc. and Hemmings Motor News was nearly our only resource. I just assumed I would never find parts for a limited-production Alfa. It took me a month of spare time work to build this solution to my brake problem.

Larry Bono
 

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The full axle replacement from a later spider or a sprint is the only realistic option. If you use the sprint axle you'll have a longer ratio and more relaxed cruising. But why change you have huge rear drum bakes which are probably as good as early discs. Its the front end that does the stopping
 

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Push hard and live
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I thought the Sprint and Spider had the same rear end ratio, and that it was the Sedan that was different.
 

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Ratios

Ratio in the parts manual depends on whether you have a disc brake (Freni a disco) or drum brake axle (Freni a Cappi) which is what I had read

Owner's manual has

Berlina 8/41, Sprint 9/43, Spider 9/43

Plus SZ manual and 2600 sprint supliment 9/43

10/43 a richiesta ( on request) for the sprint

So Don you saved me wasting my time swapping in a sprint axle to reduce the high revs of the spider. I'll do a basic rotation check to see what I have got in my spider and spint axle.
 

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Discussion Starter #10
Thanks. That saves me the hassle. The only benefit would be to fit wire wheels, which I have been told by Borrani that their solution works with the rear drums. Staying stock.
 

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front disc conversion

anyone convert the front 2000 drums to 2600 discs or other style discs?

Ive read that the 2600 hubs will fit a 2000 but not vise versa

do all you need to swap are the hubs or jsut pull the drum assy and fit discs to existing hubs?

thanks
 

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Push hard and live
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I've got nearly 6,000 miles on my 102 since restoring it. The stock brakes work great, and many of my drives are up and down to Lake Tahoe. I didn't bother relining my shoes when I did the rebuild, as there was plent of meat. No adjustments necessary so far.

And those big finned drums look perfect showing through the wire wheels.
 

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I want to correct a mistake in my previous post (# 5 in this thread) regarding the diameter of the 2600 hand brake drum which is cast with the rear disc. My memory was faulty and the correct diameter is 8 inches, not 7 inches. I discovered this today while disassembling the rear axle in preparation for installing my rebuilt differential. The Triumph TR 7 rear drum brakes are also 8 inches and they were used to build working hand brakes on my car. Sorry for the mistake.
Larry Bono
 

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I have a complete rear axle, with disc brakes, from a 1964 Spider that I parted out (way too much rust). I originally thought I might put is in my 1962 2600 Sprint with drums, but that might require me to put a brake booster back in the car. Let me know if you are interested and where you are located. The assembly is really heavy, so shipping alone will not be cheap.
 
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