Fitting e30 rear calipers to e21 trailing arms
Posted: Wed Jan 04, 2012 1:22 am
I was sorting out a set of e21 323i trailing arms to sell and I had as I had a set of e30 rear calipers sitting around I thought I would fit them, as you can see the e21 and e30 calipers are pretty close, the e30 calipers are a more modern design have a slightly larger piston and a far superior brake pad choice.
To modify the e30 calipers you need to drill the m10 mounting holes out to a 10mm hole on the caliper carrier, as on the e21 trailing the calipers bolt to the arm but on the e30 the arm bolts to the caliper. Also on the e30 caliper carrier there is a raised section between the mounting holes need to be ground down. The bits to be modified are shown below.
Modified caliper carrier looks like this
Next just stick the caliper back together
Then I cut down some drive shaft bolts as the shoulder on the bolt was spot for length
Then just a case of bolting the caliper up
The e30 brake hole fits but is about a 1" to long so a e30 stainless flex would be better (easier to bend).
J
To modify the e30 calipers you need to drill the m10 mounting holes out to a 10mm hole on the caliper carrier, as on the e21 trailing the calipers bolt to the arm but on the e30 the arm bolts to the caliper. Also on the e30 caliper carrier there is a raised section between the mounting holes need to be ground down. The bits to be modified are shown below.
Modified caliper carrier looks like this
Next just stick the caliper back together
Then I cut down some drive shaft bolts as the shoulder on the bolt was spot for length
Then just a case of bolting the caliper up
The e30 brake hole fits but is about a 1" to long so a e30 stainless flex would be better (easier to bend).
J