E38 caliper question

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Rob_farmer
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Post Wed Nov 27, 2013 10:24 pm

Guys,

As per zone brake upgrade wiki, looking to upgrade brakes. E38 730i/735i 4 cyl. Brembo calipers on my E30 51mm struts. Some people have said E38 comes with Brembo`s only on front(is that 101% correct?). Is it possible to fit all 4 Brembos from E38(two sets from front?) to E30 ?

I`m struggling to find brackets/adaptors. Any advice?
I`m driving E30, 1989, 325i, 4 door. Restoring 1990, 4 door.
pacerpete
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Post Thu Nov 28, 2013 11:06 am

E38 calipers will not fit without loads of bodging / spacers etc. That is why they are nigh on worthless.
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Rob_farmer
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Post Thu Nov 28, 2013 11:09 am

I do understand that, they were never designed for E30, but any non E30 calipers will need custom fabrication of some kind of brackets/adaptors. I chose E38 as I can get them cheap and many available.
I`m driving E30, 1989, 325i, 4 door. Restoring 1990, 4 door.
pacerpete
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Post Thu Nov 28, 2013 4:04 pm

The reason they are worthless is because they are completely unsuitable. Unlike E31 840 Brembo calipers........
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Rob_farmer
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Post Thu Nov 28, 2013 4:05 pm

Why unsuitable ?
I`m driving E30, 1989, 325i, 4 door. Restoring 1990, 4 door.
pacerpete
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Post Thu Nov 28, 2013 4:14 pm

IIRC the 'pitch' and the disc clearance to mounting points are incompatible . I have seen them on a M3 , which is obviously different to a lesser 4 stud turd, and the install was shocking and epic for all the wrong reasons. IIRC there was 27 mm of 'spacers' going on and lots more medieval activity to allow them to 'fit' :eek:

Meanwhile 840 calipers would have bolted straight on and worked out of the box. Alas, 840 calipers cannot be bought for the price of a large mixed kebab :(
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Rob_farmer
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Post Thu Nov 28, 2013 4:22 pm

Damn :( What is the best kit then with least ugly mods and fabs +cheapest on stock 4 hole E30 51mm struts?
I`m driving E30, 1989, 325i, 4 door. Restoring 1990, 4 door.
jimbom30cab
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Post Thu Nov 28, 2013 6:31 pm

http://www.ebay.co.uk/sch/i.html?_trksi ... &_from=R40

would these be the correct ones then?
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Rob_farmer
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Post Thu Nov 28, 2013 6:34 pm

Yeah Jim, seems like. But how come 5L 8 series has such small calipers with just one piston, while E38 3L has huge 4 piston Brembos?
I`m driving E30, 1989, 325i, 4 door. Restoring 1990, 4 door.
jmc330i
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Post Thu Nov 28, 2013 6:50 pm

jimbom30cab wrote:http://www.ebay.co.uk/sch/i.html?_trksi ... &_from=R40

would these be the correct ones then?
Yes, they are 840 calipers, no they aren't 4 pot Brembos.

The Brembo 4 pots were an option on the E31 (and E38). If the option box wasn't ticked, then single pot sliders is what you got.
James
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'93 318i touring 16v
capnmchl
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Post Thu Nov 28, 2013 7:02 pm

jmc330i wrote:
jimbom30cab wrote:http://www.ebay.co.uk/sch/i.html?_trksi ... &_from=R40

would these be the correct ones then?
Yes, they are 840 calipers, no they aren't 4 pot Brembos.

The Brembo 4 pots were an option on the E31 (and E38). If the option box wasn't ticked, then single pot sliders is what you got.
Like these?

http://www.ebay.co.uk/itm/BMW-840CIA-85 ... 3a867f7a3c
jmc330i
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Post Thu Nov 28, 2013 7:44 pm

Looks like em.
You could still get them new from BMW (often cheaper than secondhand!), but they dont come with the BMW letters on them anymore.

They fit straight on to the E30 M3 front strut and you can use E46 M3 discs, but due to the E46 disc offset, you need a spacer to fit between the hub and disc to align the disc in the caliper (the spacer needs to be machined 100% perfect for the disc to run true). Or you can run a bell and rotor setup with a thicker bell to act as the spacer.
This set up will fit inside the standard E30 M3 16" BBS wheel but due to spacer required for the disc, you will need to run E36 offset wheels to keep the wheels inside the arch.
James
'91 325i Sport
'93 318i touring 16v