M Stands For “Make It Fit”

18 Nov M Stands For “Make It Fit”

We’re engineering as hard and as fast as we can this week, all in the name of fitment.

Although, we’re not referring to wheel fitment. Currently, we’ve got Ashley’s E90 3-series sedan up on a lift, wheels off, ready to party. And by party, we mean “replace the stock 3-series front brakes with an E90 M3’s front brakes.” This has been one of our big fabrication tasks this week, as the front brakes are not a simple unbolt-and-bolt exercise. To replace the stock rotors, calipers and brackets with those of an M3, there’s a bit of work involved.

Originally, we wanted to get everything to fit up nicely with the stock brackets. Thanks to differences in part sizes, we had to machine down the calipers just a tad. Sure, it made them shiny and fixed the fitment issue, but not everybody wants to take a rapidly-spinning drill bit to their M3 front brake calipers. Therefore, we went about searching for a new answer. That answer? The bracket. Here’s a picture of the stock one in the caliper, followed by our prototype:

This bracket is made from aluminum, but don’t worry, it’s only for fitting and prototyping. The final product (the one we test on the street) will be made from steel; to put aluminum through the stress that that bracket experiences, it would last maybe 10,000 miles or a few laps on the track before cracking. We chose it for our prototype material, though, because it only takes 2 hours to cut and prepare, as opposed to the 8-hour job that would produce just one steel bracket. No matter, though; AJ and Eastway are talented engineers and they got fitment and everything down in just a couple days.

There’s plenty more to be done before we start bolting everything together, but stay tuned, more updates are on their way! Once this project is done, all it should take to bolt M3 front brakes onto your E9x 3-series is our bracket.