Solid or braided line to the rear brakes

[alangbaker]

I've heard differing opinions on this.

I've got an 89 Van Diemen that has a braided line from the rear master cylinder all the way to the tee fitting for the two lines to the calipers. Is this a problem? Will the pedal be unacceptably soft with that much braided hose or will it be fine?

Your thoughts?

P.S. -3 lines; AN3 fittings (that's right, isn't it?)

[BLS]

Might want to mention the line size, -3, -4 etc. -3 usually not considered a problem, but never better than solid.

[alangbaker]

Might want to mention the line size, -3, -4 etc. -3 usually not considered a problem, but never better than solid.

Right you are!

-3 lines. AN3 fittings.

[Tiago Santos]

It'll be fine.. Braided is easier to install, but a lot more expensive!

[Steve Davis]

I use steel line for the long run from front to rear, mostly because it's CHEAP and probably better as well. You can get the steel line from any autoparts store... and it stands up to a LOT of crap and it does NOT expand .. AT ALL .. under hard braking.

Yes - Aeroquip is "almost" as good for braking, but costs over 10 times as much.

Why? Why NOT (steel) ??

Steve, FV80

[Tiago Santos]

I use steel line for the long run from front to rear, mostly because it's CHEAP and probably better as well. You can get the steel line from any autoparts store... and it stands up to a LOT of crap and it does NOT expand .. AT ALL .. under hard braking.

Yes - Aeroquip is "almost" as good for braking, but costs over 10 times as much.

Why? Why NOT (steel) ??

Steve, FV80

I agree! However.. The last time I had to replace a brake line on my car (which had a braided line to begin with..), it was a lot easier to buy a braided line and be done in 5 minutes, rather than having to figure out how to bend and route the solid line through the car.. I'd also have needed flare tools, bending tools, etc.

Were I to do it again today, I'd probably have saved the almost $100 I paid for that line and figured out how to bend the solid line. But at the time, I think I made the right choice

[Zonker]

I agree! However.. The last time I had to replace a brake line on my car (which had a braided line to begin with..), it was a lot easier to buy a braided line and be done in 5 minutes, rather than having to figure out how to bend and route the solid line through the car.. I'd also have needed flare tools, bending tools, etc.

Some years ago I got a deal on some braided line so I did my sports racer that way all the way back. No adapters to fool with and no flaring.

IMHO it is worth the money just to simplify things. You only buy it once.

[alangbaker]

I use steel line for the long run from front to rear, mostly because it's CHEAP and probably better as well. You can get the steel line from any autoparts store... and it stands up to a LOT of crap and it does NOT expand .. AT ALL .. under hard braking.

Yes - Aeroquip is "almost" as good for braking, but costs over 10 times as much.

Why? Why NOT (steel) ??

Steve, FV80

Well the thing for me is that I've already GOT braided installed. The previous owner is trying to suggest that his soft pedal problems were caused by that, rather than by how well the system was bled, etc.

So for me the question is:

Is the braided long run to the back a real problem that I need to address?

[Steve Davis]

...
So for me the question is:

Is the braided long run to the back a real problem that I need to address?

I don't think so....
Steve, FV80

[alangbaker]

I don't think so....
Steve, FV80

It's what I thought, too, but good to hear from someone else.

[ianashdown]

Does anyone use -2 hose for the brake system?

[Neil_Roberts]

Even top echelon pro cars have been plumbed with braided brake lines as standard practice for decades, because it's quick and easy. It's not a problem for pedal stiffness. Hard lines are a little bit stiffer than braided, but not much. A downside of braided lines is that vibration makes them act like a dull saw, so they will erode through wiring insulation eventually. It's best to sleeve them in heat shrink tubing before final installation.

I prefer to minimize the number of fittings and joints in the system because each one costs money, time, and weight, and it is a potential leak source.

[DanW]

Ron Chisholm said some of the atlantics he prepared used -2.

[alangbaker]

Even top echelon pro cars have been plumbed with braided brake lines as standard practice for decades, because it's quick and easy. It's not a problem for pedal stiffness. Hard lines are a little bit stiffer than braided, but not much. A downside of braided lines is that vibration makes them act like a dull saw, so they will erode through wiring insulation eventually. It's best to sleeve them in heat shrink tubing before final installation.

That's not a bad thought... I might be able to get that done before I finalize everything...

I prefer to minimize the number of fittings and joints in the system because each one costs money, time, and weight, and it is a potential leak source.

Makes sense to me!

[DaveW]

Well the thing for me is that I've already GOT braided installed. The previous owner is trying to suggest that his soft pedal problems were caused by that, rather than by how well the system was bled, etc.

So for me the question is:

Is the braided long run to the back a real problem that I need to address?

I have braided front to rear and all throughout the braking system (F2000 with Alcon disk brakes front and rear). My brakes are VERY firm. So, braided line is not the cause of spongy brakes, IMO.

[Brian.Novak]

We generally have run braided for the ease of use, but have ran steel on many of our F500s.

I always heat shrink my lines now, much better from a durability point of view and just nicer overall. Learned that, and many, many, other tricks, from Mr. St. Clair.

[alangbaker]

I have braided front to rear and all throughout the braking system (F2000 with Alcon disk brakes front and rear). My brakes are VERY firm. So, braided line is not the cause of spongy brakes, IMO.

Thanks. I believe I see a consensus emerging.

We generally have run braided for the ease of use, but have ran steel on many of our F500s.

I always heat shrink my lines now, much better from a durability point of view and just nicer overall. Learned that, and many, many, other tricks, from Mr. St. Clair.

Is it possible to get heat-shrink tubing on over top of brakes lines that already have fittings on the end? I like the idea, but I don't want to have to start over.

[DanW]

Thanks. I believe I see a consensus emerging.



Is it possible to get heat-shrink tubing on over top of brakes lines that already have fittings on the end? I like the idea, but I don't want to have to start over.

Its worth a try. The Wurth heat shrink is pretty good.

[Neil_Roberts]

Thanks. I believe I see a consensus emerging.



Is it possible to get heat-shrink tubing on over top of brakes lines that already have fittings on the end? I like the idea, but I don't want to have to start over.

McMaster has numerous varieties, with the shrink ratio listed. There must be a winner in that group.

[ghickman]

I use .5" shrink tubing which will slip over a -3 fitting and it easily recovers down to the diameter of -3 hose.....5/8" works also.

Just did my new car this way, ran the brake lines thru the A Arms with shrink tube on it where it passed thru the A Arm then put the ends on. A bit of a PITA but it looks bad ass.

[KevinFirlein]

I have used braided -3 as standard, -2 at owners request on every car I have ever built. And yes the Champcar and Indycars I've tested also used the braided line as well. Hardline will provide a slightly harder pedal but its hardly noticeable.

Its is a good idea to insulate the long runs of braided line because as noted they are abrasive when they vibrate and rub agaisnt items. When I build Formula Atlantics I use a heat shrnk material on the brake and clutch lines going to the rear so that they dont carve away at the tub were they pass thru.

The previous owner is likely parrotting incorrect info that was given to him at some point and he stopped looking for the real cause of his problem. Either bad bleed, caliper seals, or master cylinder seals.

[george schilling]

I'm fairly new to C-mod so I appreciate this forum greatly. I have braided line throughout my RF-84 and last weekend had some problems with the AN-4 clutch line that I could not remedy. Not knowing I had .030 wall thicknesses, I had only olives to fit .040. I'm considering my options and hopefully can get some expert guidance here.

My brakes are plumbed using AN-3 stainless flex tube. The clutch line is plumbed using AN-4. The AN-4 tubing has the .030 walls. I'll be using mechanical fittings as opposed to crimped.

Here are my questions.

1. Is there any reason why the clutch line can't be AN-3 so I can carry fewer spares?
2. What are the advantages of using the .030 wall thickness? the .040 wall thickness?
3. Is there a need to periodically replace all the braided tubing in the car?

Thanks in advance for the help!

[Steve Demeter]

The clutch line is bigger because it has to move more fluid than the brakes.

I can not speak to the wall thickness of hard lines. My car has braided lines from the MC's to the other end.

Never heard of a braided teflon line going bad unless there was some sort of damage. Say from a wheel coming off in a crash.

They are pretty tough.

[Rick Kirchner]

you can get goodrich line covered with tubing in a variety of colors. I found a potential drawback with the clear tubing - I had a slight fluid leak at a fitting (use ATE blue) and the braid wicked the fluid way up under the clear tubing. I eventually fixed the leak but the fluid continues to leach out from under the tubing, making me think I still have a leak........

[Brian]

Many cars use -3 for the clutch. -4 is considered better (and I use it) since the fluid moves very fast and can cavitate with -3 more easily than with -4. I have no idea what your issue with wall thickness is - I've never encountered an incompatibility with hose dimensions and since they originated with NATO AN standards, I wouldn't expect to. I don't know what a "mechanical" fitting is, so I can't comment on that either.

Brian