E32 front brakes

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AndyS

E32 front brakes

Post by AndyS »

I've got hold of some E32 735/750 front calipers to fit to my '89 UK 635.

Reading the various posts & articles I gather that fitting these won't affect pedal travel too much, especially if I fit braided hoses at the same time.

I know I'll need a 750 master cylinder if I fit E34 540 rears but can I do this upgrade in stages?
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Re: E32 front brakes

Post by ron »

AndyS wrote:I've got hold of some E32 735/750 front calipers to fit to my '89 UK 635.
I think you will need the discs as well.
They are ALWAYS rustier than you thought!!!!!!
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'87 M #367
'88 High line.
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dividedbydrew

Re: E32 front brakes

Post by dividedbydrew »

AndyS wrote:I know I'll need a 750 master cylinder if I fit E34 540 rears but can I do this upgrade in stages?
You do not need a 750 master cylinder if you upgrade front and rear brakes. This is a common misconception. A 750 master cylinder will reduce pedal travel but maybe you don't want that. Maybe you want more brake feel and not just instant on brakes. Read some of the links I posted in this thread viewtopic.php?t=11847&highlight= It probably comes down to personal preference for brake feel but don't just assume you need to swap a part. I'd upgrade just the calipers (and rotors) first and see how it feels to you and then decide if you think the MC upgrade is worth it. Just my 2 cents.
Drew
AndyS

Post by AndyS »

That's good news.

Replacing the m/c on a pre '87 rhd is ok because everything lines up (m/c is on the left). Post '87 rhd have the m/c on the right. This gives them a head start in brake feel but makes fitting the 750 m/c a pain since the pipes are on the "wrong" side. This means replacing the brake pipes round the back of the engine all the way across to the other side.

Braided hoses tighten pedal feel so I may do those at the same time.
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Brucey
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Post by Brucey »

the pipes are V tight on the RH side MC type if the E32 MC is fitted; best solution I have seen is to make up new hard lines in copper, this way they can have a mega-tight bend just before the MC side entry and you can still get at the spark plugs etc. I saw an installation like this recently and I was impressed with how tight the bends were.

I suppose you could get stainless flexibles made up with a right-angle connector on the end but I doubt it would run as tight as the copper can.

I's stick with the E24 MC + braided hoses unless it was really bad though....

cheers
~~~~~~~~~~~~Brucey~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
AndyS

Post by AndyS »

Think you're right.

I'll see how it goes with the fronts then try the 540 rears before I worry about the m/c.

Life's difficult enough without complicating it.
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Post by ron »

Brucey wrote:...the pipes are V tight on the RH side MC type if the E32 MC is fitted; best solution I have seen is to make up new hard lines in copper, this way they can have a mega-tight bend just before the MC side entry and you can still get at the spark plugs etc. I saw an installation like this recently and I was impressed with how tight the bends were.
As per this:-

Image
Image
They are ALWAYS rustier than you thought!!!!!!
'85 M #228
'87 M #367
'88 High line.
'10 X5
‘84 Alfasud 1.5 ti
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Post by ron »

AndyS wrote: .........this means replacing the brake pipes round the back of the engine all the way across to the other side.
Not too bad a job with the cylinder head removed! A nightmare otherwise!!
They are ALWAYS rustier than you thought!!!!!!
'85 M #228
'87 M #367
'88 High line.
'10 X5
‘84 Alfasud 1.5 ti
wattsmonkey
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Post by wattsmonkey »

As per the above: try it first and see.

I've got 540i brakes on the front and E34 525i brakes on the rear (i.e. not vented rear) with braided s.s. hoses and Greenstuff pads, using DOT5.1 brake fluid and I love the brakes, especially compared with the old set up.

I've also got a brand new 750i MC which I simply haven't bothered to fit as I - personally - don't feel the need: the brakes feel fine.

The only reason I'd do so would be to make the sixer more drivable for people used to modern cars (i.e. my wife), but seeing as she's never wanted to drive the car at all it's not an issue!

Having said this, I had a drive in a newish 325i and could not believe how light the steering was, and how sharp the brakes were!

Rob
"Most of it necessary; all of it enjoyable." LJKS
'84 635CSi, dogleg...itbs and supercharger????? Eaton Mess
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