Front Brake "Upgrade" Part 2 - E46 Brakes - Installation


Tools needed:
  • 6mm Allen
  • 7mm Allen
  • 17mm socket
  • 16mm socket
  • Short extension
  • Socket wrench of choice
  • Breaker Bar/Impact Gun
  • Lube
  • Brake Cleaner
  • Large Screw Driver
  • Hammer
  • Bolt loosening spray

Obviously we are going to jack the car up. Please be safe, make sure the car with not roll while being jacked up. Use a jack stand. You know the normal precautions. Remove the front wheel(s).

   There are two 16mm bolts holding the caliper in place. In this picture, on the drivers side, see that black wire? That is the wear sensor. These are on one side only in this case the driver's side. What these do is: when the material on your brake pads gets worn away, eventually these come in contact with the rotor. When that happens you will see a light on your dash informing you of such. So you may need a new pad wear sensor if this has already happened.
  You could also upgrade your brake pads, rotors, or lines. That is entirely up to you. Swapping rotors or pads is an easy go. Getting into lines, or calipers involves brake bleeding. Every car guys favorite activity of course. One word, quality power bleeder. Made life better for me. 
  Given the caliper is sitting out further I was worried about the wear sensor wire being too short. This was not the case. Getting the wear sensor off, whilst holding the caliper in hand, can be a little tricky. Patience and a strong arm is key.
Stock E36 Rotor, Bracket, and Caliper.
E46 Rotor, Bracket, and E36 Caliper Installed.

  Installed. Wait, I thought you said you had painted the caliper as well? Yes, I did, however, someone is borrowing my compressor and I did not have the time, nor the assistance to foot bleed them. For now I'm running the non painted calipers, with the painted brackets.

  Sits just fine with the stock 16" Sport Wheels. So how does it feel? Good. I scuffed off most of the rust on that rotor. The pads will eat off what's left. The rotors are straight, no wobble. This whole effort was to see what the difference was between these two sets of rotors, calipers, and brackets. I wanted to work out what was interchangeable. The budget here was very low, obviously, however, the results are tangible.

  BMW designed the braking system well in the E36 and E46. For me, if I can get parts in a newer design, that a little better, for just a few more dollars, I'll give it a shot. In this case this whole project cost me about $35, not including my time. Easily more for after market rotors, pads, ect but, now I can look into those avenues knowing that it will all work even better.


Front Brake "Upgrade" Part 1 - E46 Brakes - Paint, Specs

  I got these awesome, super stock calipers off a wrecked up 01 325i. Already painted red for me. Extra performance right out of the bag folks!


  Why would you try putting these on an E36? I'll tell you. The E46(99-05) 325 & 328 have 11.8 inch rotors up front. The stock e36 rotors on my car are 11.2. I'm gaining about a .6 inches. Not much but, it is an improvement in rotor circumference.

  The calipers are identical, the pads the same, it's the carrier bracket that differs. These will increase my radial braking surface resulting in a whopping 6% braking increase over the front axel! Can you even believe it? A laugh and giggle there for sure, obviously. However, all be it a small increase upgrading to E46 rotors and calipers all around, with stock pads, will accumulate around a 13% increase total which, is something.

11.8 inches on the E46 325, 328 rotors
  I was curious about the sizing of the piston diameter on my stock E36 calipers versus the stock E46 calipers. Some pictures for confirming sizes of the piston diameter below.
  • The serial numbers on the calipers differed slightly. 
  • The weight was about the same. 
  • The piston diameter was also the same.
2.085 outer roughly.
1.565 inner roughly.
.250 (1.4) thickness.
The bracket was certainly different. It moves the caliper out further from the spindle to accomdate the larger rotor. The slide pins are in the exact same location allowing for use of an E36(325, 328) or E46(325, 328) caliper.
Caliper brackets side by side. Its hard to see the spacing of the threaded holes at this angle. Sorry. They are just a bit more than a 1/2 inch different.
 Prep and Paint

  Of course before I put these on my ride Id like to make them, not red. A good spray down with brake cleaner. Some medium grit(220) sandpaper to get started. I used the rotary tool to get in the tight spaces. This creates a good bit of dust, please be cautious and wear a face mask here. If I had a media blast cabinet, that would have made this a dream. Its on my list.

Tools of the trade for prep
  • Heavy wire brush
  • Large pliers
  • Rotary Tool with a metal brush on it
  • 120 Grit Sandpaper
  • 220 Grit Sandpaper
  • Brake Cleaner
  • Not sure what I was doing with the wheel cleaner there

  After sanding and a rinse. They are ready for paint. I'd advise removing the carrier pins. This can be done with a 7mm Allen wrench or socket.

  They look so good after a good spray. Unfortunately as with most spray paint techniques, these may not hold their color forever. We will see. A lot of people really have great success with powder coating however, the cost is substantially more. I do not have that kind of cash flow for this project.