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Coming Soon: E30 Secondary Caliper Mounts

March 14, 2017 Braking, General Talk 0 Comments

In the summer, when the weather is nice and you can actually feel your hands outside, our work breaks typically consist of being hooligans in our e30 street cars. A product we have thought about making for a while is a simple mounting provision for a secondary set of calipers for the rear of the e30’s.

A solution where minimal work for installation is what we were aiming for. Being that there are only two mounting tabs for brakes on the rear trailing arms we knew that trailing arm modification would be unavoidable.

Our design mounts a factory secondary caliper right next the the stock unit. All that is required to have the secondary unit capability is some trimming of the dust shield and welding a third ear to the arm. The positioning of the new ear is attained easily by simply mounting the bracket up to the existing points and tacking the new ear in its home prior to final welding. This design requires only the rear brakes to be removed for assembly. Our prototype model (seen below) is as exciting as shoe shopping on a Sunday, but it got us to our test pieces.



This approach, to us, made the most sense, as you can retain the factory dust shield and e-brake for street driving if needed. This design also ensures the entire secondary set-up can be removed easily.



In my previous article I brought up the joys we often experience when working with war-torn factory parts, this was one of those joyful experiences. Anyhow, 3-d printing our pieces allowed us to perfect positioning and material clearances.



A few rough sets of billet brackets were cut out. These pieces were laser cut and then milled. The final production pieces will each be machined from solid billets, among other differences.



We got the first set assembled on to a non-street-car, street car which will soon be ready to go out for some testing. We could go out in the snow and get some tank slappers going, but locking the rear tires up on slushy (non-public) roads is hardly a viable shakedown for these first-offs.



The production units for this kit will be cnc machined from aluminum. The brackets will be engraved and anodized black. Plated steel top hat inserts are press fit at each mounting point. This ensures the brackets can be removed and installed consistently without causing damage or deformation to the aluminum body.

Each kit will include a pair of mounting brackets, a pair of steel third position mounting weld ears and a set of properly spec’d hardware.

In time, if desired, this platform could be revised to carry alternate calipers as well, since the trailing arm mounting positions will not change.

Stay tuned for more updates.



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