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Greek · Alfasud Joined: 08 Apr 2008 Posts: 33

Well i decided to replace my rear drums with rear disks from a 16v model. My car is a Sprint 1.5 '85 but the same procedure can be done in 33 also and maybe in Suds.

Along with the replacement of the drums i upgraded also front disks and also installed high pressure tubes.

Here we go.

First i got a used rear axel from a 33 16v and front disks. As discussed in another post there was already installed on that an antiroll bar.

My fist thougt was to just replcace the whole axel with the one from 33.So i decided to take car of it and started to paint it. Here is the result ( Black hammerlite that doesnt need primer half an hour job).

Then i decided to paint red the antiroll bar and remove the internal disk covers...

So far so good. The axel really looks good. I have also removed the disk calipers and gave them a good clean with swaz soap and painted them with red heating paint. It gave them a good mat red color.

After they were all ready it was time to put them back on the axel....

Here is the result...

Well i have encountered the first problem ... The difference between Sprint and 33 is the place of the mountings of the axel.On 33 all 4 are facing forward (Look 2nd picture above) but on sprint the 2 short are facing back. Even the short moutning bars are slightly different so there were no much even if we changed direction.if you have a 33 then no problem go ahead and replace it.If you dont have an axel but just disks and calipers then continue reading...

So plan B. Keeping my old axel and just replace the drums with calipers... We checked that drums and calipers have the same mounting holes so it was possible.
Removing drum from rear axel. Take a good look at the junction point of the brake tubes because this is important as this is the only difference in the setup between drums and rear disk setup.

Here is the axel again on the car but withount the drum. On the same place we will fit the caliper

We used the front mounting from the new axel with the antirollbar .Here is a pic..

Another look on the antiroll. It is important that the vertical bar should be almost under mounting point in order to work properly.

Here is the rear caliper installation. As you can see no difficulty to install it on the old axel..

Done , the caliper is on . Just bolt in..

The next interst thing was the brake lines. We moved the distributor back to the car floor instead of the left place it was with the drums...

A closer look..

On the right side we had to find an extension or manufacture one. Fortunately we found one in the scrap part and used it.. But if you have found a complete rear axel dont forget to have also the brake tubes. it will save you some trouble. Also take the handbrake cables....

Finally . we had to replace the hand brake cables with those for calipers. I am guessing that this can be done in older models with sud brakes if someone wants to have rear handbrake..

After finishing rear handbrake we went on the front . Here is the 16v caliper and ventilated disks. Simply bolt in . I have painted also the calipers and they look great.

Ok , i forgot to mention one crusial thing... After we finished the circuit we had to recalibrate the brake regulator. We placed a hydraylic lever on the center of the axel while on the ramp so that the rear wheels are on the air and then we placed weight on the regulator switch, something about 6kgs.

BigAl · P4 Joined: 06 May 2003 Posts: 2992 Location: U.K Surrey

nice, do you know how much diffference in braking force disks are compaired to drums, would the back end drift out in corners? I never got how to adjust the break force balance thingy
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x2 33 16v
pictures http://www.alfa-pages.co.uk/viewtopic.php?t=5203

Greek · Alfasud Joined: 08 Apr 2008 Posts: 33

Well adjusting the regulator with 6 kgr weight is the default setup in order to work ok so no back drift.
In my case i have seen geat change in performance but :

- I had small leak in the drum seals so they didnt brake as they should
- I also installed rear antiroll bar that changes the attitude of the axel
- Installed high pressure tubes
- Also installed front disks and calibers.
-Changed brake fluid from DOT3 to DOT4

Maybe for someone with drums in excellent condition the difference wouldnt have been so big but drums have problem with heat and constant braking.On the other hand they require the minimum in terms of servicing.
Now it stop really hard if needed and brake pedal has better feeling and also handbrakes works as it should. I have tested the car on track with drums and i must say that after 4 (small) laps i didnt had any brakes ... I tried the same setup with disks and they didnt show any marks of weakness.

Admin

Delfos33 · Posted: Fri Dec 12, 2008 7:21 pm Post subject:

Very good project Greek!
I'm planning to do the same thing on my 33 but i have 2 questions.
a. Can you replace the bearings separately or you have to buy a new hub in order to replace them?

b. Are there any piston caliper service kits?

Regards,
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1992 33 1.4 Marelli R.I.P
1991 33 1.4 Bosch alive

Greek · Alfasud Joined: 08 Apr 2008 Posts: 33

Thanks .
Well i havent changed bearings but i opened the caps and lubricate them with fresh stuff but i guess you can change them. I dont know if they are any kit for caliper servicing but i know you can change seals on them. I have cleaned them with industrial soap (SWAZ) which is powerfull amd not with another chemical becaulse it would ruin seals and then i refreshed also the lubricant on the calipers axels( those that move the rear end of the caliper.

I can tell you the shop i made mine , they are good friends and they know their stuff...

SPRINT · Posted: Tue Jan 06, 2009 12:53 am Post subject:

Here my Sprint conversion with photos and report in spanish Sad

http://perso.wanadoo.es/jbrunet3/frenscast.htm

Ciao!SPRINT

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Alfa Sprint 1.7 QV forever!!!!

Greek · Alfasud Joined: 08 Apr 2008 Posts: 33

Hi Sprint..

Did i saw correctly?
In you rear axel all connecting rods are facing on the same direction? Because in mine the sort on are facing back...

Greek · Alfasud Joined: 08 Apr 2008 Posts: 33

I think know i can post my impressions after the upgrade since its been quite a time of use. Now that the system has worked and the brake pads are used i can say that it worthed it. i have tested them in panic brake , in heavy rain and in constant use.

The behavior was excellent , i never felt betrayed , the car was stopping straight away and without locking the wheels . High pressure tubes also changed the feeling on the brake pad, more responsive sensation so i reccomend it higly. Also DOT 4 fluids were better that original DOT 3 . i didnt use DOT 5.5 since i am not using Sprnt in track day but in everyday use.