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Drum to disc conversion advice
mikeb - 6/10/19 at 09:48 AM

I currently have standard Sierra drum setup. I'm shortly going to strip down the rear end. Not happy with my drum setup atm and rather than spend money sorting that out I'd like to put rear calipers on. I've got push in driveshafts.

Searching threads I can't find a guide of the most cost effective route. Sierra parts seem expensive compared to VAG. Does anyone have a list of parts that will fit under standard offset 15s?
Sierra cosworth solid rear discs?
Cailper adapter plate or Sierra disc hub?
Which vag calipers? Seat Leon cupra 04?

Any advice or other cost effective options.


[Edited on 6/10/19 by mikeb]

coozer - 6/10/19 at 02:45 PM

I would stick with drums.. are they the puny standard 9" jobs?

Get a set of 10" drums off a xr4i, the shoes are 3" wide and are very good.. new parts are still available from steealers and they fit under 13" wheels no problem.

perksy - 6/10/19 at 09:27 PM

As above, I'd stick with Drums

To be fair their designed to work on cars a lot heavier than a 7 when working correctly (XR4 Included)

Slater - 7/10/19 at 09:09 AM

As above, stick with drums. I believe they are lighter than the disc set up too.

rusty nuts - 7/10/19 at 09:31 AM

Agree about sticking with the drum brakes , properly set up they are more than up for the job.

nick205 - 7/10/19 at 02:51 PM

I used Sierra drums on the rear of my MK Indy build and they were more than adequate. Cleaned the drums up and painted them to make them look better, new shoews, wheel cyclinders and hand brake cable and everything worked great. Hand brake was easy to set up and held the car fine even on steep slopes. As above they're were designed for (and fitted to) much heavier vehicles so should work fine on lower weight kit cars.

flak monkey - 7/10/19 at 06:02 PM

Having done the drum to Wilwood discs and calipers conversion I would say dont bother at all. They are terrible in comparison and you'll never heat drums up on the back of a locost to the point where you have a problem.

I have all the calculations somewhere to back up the real work experience... wish I'd believed the numbers to be honest...


mikeb - 9/10/19 at 12:22 PM

Thanks all, I'll take another look at my drum setup. Fancied another winter project so still interested in parts needed.

big_wasa - 9/10/19 at 03:27 PM

If your looking for a Diy project then take a look at this post

Little dinky mx5 calipers on 221mm discs. Just to note Dafs hubs seem to be 180deg rotated to most others so if he does happen to have some plates left over they may need adjusting for your set up.
The hubs need turning down loads and they are very hard, maybe some kind of chromoly. And the discs will need spigots to center them.

They add bling and I think they add value but I donít think they do anything for the car itself.