# E36 M3 rear brakes onto E36 325



## chukiechz (May 15, 2002)

ok, I've talked to someone first hand that has done this conversion. He told me that the M3 calipers will bolt right up with no problems on the 325 trailing arm. This was for a race car, so the parking brake was not installed. 

I bought a set of calipers and rotors as well as the parking brake parts, and Im gonna try this out. Kinda nervous about the parking brake. I've never fiddled with it, let alone removing it and replacing it. For $150, I guess its worth a shot

Hopefully I'll get to it in a few weeks


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## The HACK (Dec 19, 2001)

chukiechz said:


> *ok, I've talked to someone first hand that has done this conversion. He told me that the M3 calipers will bolt right up with no problems on the 325 trailing arm. This was for a race car, so the parking brake was not installed.
> 
> I bought a set of calipers and rotors as well as the parking brake parts, and Im gonna try this out. Kinda nervous about the parking brake. I've never fiddled with it, let alone removing it and replacing it. For $150, I guess its worth a shot
> 
> Hopefully I'll get to it in a few weeks *


Yo, come to TechSession 7.0 and we'll take a look.

Why does the parking brake need to be disconnected?


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## chukiechz (May 15, 2002)

when's tech session again? Thats a great idea!!

I forget the reason why, but I think the dimensions are different between 3XX parts and M3 brakes. Possibly the diameter?


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## The HACK (Dec 19, 2001)

chukiechz said:


> *when's tech session again? Thats a great idea!!
> 
> I forget the reason why, but I think the dimensions are different between 3XX parts and M3 brakes. Possibly the diameter? *


May 31st, starts at 10:00am at B&M Racing in Chatsworth www.bmracing.com.

If the hub dimension is the same then you don't need to pull the parking brake. You DO need to do a brake fluid flush so bring a couple of quart of what you usually use.

The only reason I can think of that requires you to pull the parking brake components, is that the diameter of the hub is the same but the hub is a lot more SHALLOW than OEM E36 brake hubs. Is the E36 M3 rear offset significantly different from E36 325is?


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## chukiechz (May 15, 2002)

I just checked bimmerforums, and I think the M3 hub has a larger diameter. I dont think I'll be able to go to chatsworth to get this done. I'll just tackle it in my garage. Just in case the poop hits the fan (which it probably will) I'll be able to take take my motorcycle to work, and fiddle with the brakes at my leisure.


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## jblack (Apr 17, 2002)

If you want the parking brake to work, you will need M3 trailing arms, M3 parking brake shoes and all the pieces parts that make them work (springs, cable, clips, etc, etc). If you want a bolt on solution that is much better (I have an 318is, same brakes as a 325), here is what to do in the rear:

E46 325 or E46 328 rear caliper, rotor and pads.

This will give you vented rears 294 by 19 versus the M3 rear, which is 312 by 20. This is the largest bolt on solution that will still let you use your emergency brake.

BTW, you can bolt on E46 330 fronts without the kingpin swap in the front. This will give you 325 by 25 fronts (M3 is 315 by 28). Yes, E48 330's have larger diameter front rotors than E36 M3's, but the M3 still has thicker ones. The E46 M3, BTW, is 325 by 28.


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## chukiechz (May 15, 2002)

Im getting all the ebrake components with the stuff. My only concern is if they'll attach the same way. Seems like you dont think it will without the trailing arm. I guess I'll have to find out when it gets here. I wouldnt think they would make them too different. If its close, I'll try to figure out a way to mount it. 

Once again, since no one has actually done it, this is all speculation. The M3 parking brake may just bolt right up. Keeping my fingers crossed for that

I've already got M3 brakes on the front, I just want to balance the braking and match the rears.


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