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Brake line diameter
Tigers - 9/3/05 at 11:23 AM

Hi!
Does brake line dimater is the same for "metric standard" cars and imperial ones?
And what is the standard brake line diameter for production cars?

Hellfire - 9/3/05 at 11:44 AM

Our internal diameter looks about 3mm which is a gnats c0ck off being 1/8" (3.15mm) I wouldn't give it too much grey matter room as it seems to be pretty incidental - it's the master cylinder which is the crucial part. Capacity flow etc...

Course I'm prolly incorrect!!!

David Jenkins - 9/3/05 at 11:49 AM

I believe that the same line is used for both types of fixings - it's all you can buy in the motor factors anyway!

Of course, the fittings themselves are different, and sometimes they require a dfferent flare shape on the end of the tube. You'll have to look in your donor manual for details (or ask again here).

Happy plumbing!

David

Tigers - 9/3/05 at 01:14 PM

Thanks!
I was considering ordering copper/nickel brake lines from Frost and there are options: 3/16, 1/4 and 5/16. I messure donor car (BMW) and it uses aprox 4.9mm outside diametter. So it looks more like 3/16... I'm just wandering if I'll be able to plumb metric type fixings on 3/16 pipe...

David Jenkins - 9/3/05 at 01:16 PM

I think 3/16" is the standard (it's been a while...)


David

Danozeman - 9/3/05 at 05:30 PM

3/16 is the standard used on most cars and the heavies is 5/16.

clbarclay - 9/3/05 at 06:51 PM

'BMW'

I would find it odd if a german car used anything other than metric.

I may be wrong but i would be surprised if it was not metric.

Mark Allanson - 9/3/05 at 07:19 PM

Metric standard is 4.75mm, 3/16 is 4.76mm, is anyone still worried?

clbarclay - 9/3/05 at 07:24 PM

Aghhh
0.01mm thats ruined my chassis build completely.

at 0.01 it will probably be the most acurate thing on my car.

britishtrident - 9/3/05 at 09:03 PM

quote:
Originally posted by clbarclay
'BMW'

I would find it odd if a german car used anything other than metric.

I may be wrong but i would be surprised if it was not metric.


Bendix and Girling were the two companies that first established hydraulic brake manufacture and standards. In continental europe and japan brake manufacturers simply adapted US and UK standards and designs to thier needs and a system evolved where all the manufactuers cross licensed from each other, this ethos remained dominnant until at least the early 90s.

I should I am biased I have a very strong distrust of continental european brake and clutch hydraulic system.

[Edited on 9/3/05 by britishtrident]

[Edited on 9/3/05 by britishtrident]

Peteff - 9/3/05 at 09:18 PM

Don't mention the war......
if I'll be able to plumb metric type fixings on 3/16 pipe. They are only metric type fittings because of the thread pattern.

Mark Allanson - 9/3/05 at 09:20 PM

..and the shape of the flare

Tigers - 10/3/05 at 08:01 AM

OK, thanx guys!
3/16 already ordered!