Patrol Diffs

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5th March 2013, 05:32 PM
350RRC

Quote:

Originally Posted by Dougal

All brake lines are braided. All lines also swell under pressure (basic physics). Lines with stainless external braiding are just for looks and are less damage tolerant than lines with internal braiding and a tough rubberised outer.
Any line can have a teflon liner regardless of it's exterior.

Where do I find these factory performance cars with stainless braided lines? Race cars are not a good measuring stick for recreational 4wd's.

Hi Dougal et al,

I have Goodridge 2'' extended braided lines on my POS, came from Paddocks. Been on for maybe 60 to 80 thousand k's. With the exchange rate now they'd cost around $100 Aus ......................................

..................for all five. Not $100 each like the ones here.

They are legal in Qld according to one of the Qld hot rod sites. (mine must have been fitted there)

They are guaranteed for life and look like something that came from the space shuttle. So skinny, no room for rubber I presume.

cheers, DL
5th March 2013, 11:44 PM
Davo

I have the same ones from the same place. I didn't notice a great improvement in braking, but the old ones had cracks on the outsides and weren't long for this world. The new ones were a great price, and should last for a very long time.
6th March 2013, 08:41 AM
Camo

Seriously brakes were the least of my worries when I had GQ diffs on my old rangie. Good luck trying to get rid of the shocking vibrations from the rear driveshaft. Felt like the wheels were about to fall off at speed:eek: Have you seen the angle:confused:
6th March 2013, 12:56 PM
Dougal

Quote:

Originally Posted by Camo

Seriously brakes were the least of my worries when I had GQ diffs on my old rangie. Good luck trying to get rid of the shocking vibrations from the rear driveshaft. Felt like the wheels were about to fall off at speed:eek: Have you seen the angle:confused:

A double-double-cardan shaft (DC joint at each end) should do it. If you can fit one in length-wise. A double CV shaft may be an option.

With single universals it could probably be made to run smoothly, but you'd have no margin for error or suspension motion.:D
7th March 2013, 12:03 PM
rick130

Quote:

Originally Posted by Dougal

IMO braided stainless lines are the brake equivalent of pod filters. Poorer function than most stock setups, less damage tolerant and more likely to damage other parts.

I disagree Dougal.

Proper SS braided hose, eg. Earls, Goodridge, Aeroquip -2 and -3 stainless braided teflon hose has less swell under pressure than any standard rubber/fabric reinforced road going brake hose, that's why they are used in aircraft and all motorsport applications.

SS braided hoses are legal in Oz if made by a certified builder.
The ends are crimped, aircraft style reusable olive, nipple and barb fittings are technically illegal, and a rubber 'shield' is fitted on/near the fitting to prevent kinking during the whip test.

I've had them fitted to the Deefer for ten years now.
Rubbed one line through on a radius arm though :angel:

Now have polyester coated hose and plastic spiral wound 'wire' around the outside for better security from 'stuff'.
7th March 2013, 12:05 PM
rick130

Quote:

Originally Posted by Dougal

A double-double-cardan shaft (DC joint at each end) should do it. If you can fit one in length-wise. A double CV shaft may be an option.

With single universals it could probably be made to run smoothly, but you'd have no margin for error or suspension motion.:D

Pretty sure Hardy Spicer here supply a DC setup to specifically fix this.

TW in the US can do it too.
8th March 2013, 08:53 AM
Camo

Quote:

Originally Posted by rick130

Pretty sure Hardy Spicer here supply a DC setup to specifically fix this.

TW in the US can do it too.

Yer 1k later. Could just buy HD rover axles for that. I don't get it.

I tried 3 types of driveshafts on mine. I'm not sure a twin DC shaft could work. I had a single DC shaft made and the DC end was at its max already. Would only get worse if you had twin DC. Might be able to get a high angle DC.. not sure. I gave up trying after spending so much money.

Rover HD axles, steering and lockers are cheap these days compared to when I had my GQ conversion done. Can safely put 35's on and not worry about breakage (pending driving style of coarse)

My brakes were mushy.. worse than the rover ones. Didn't really care though. Car was crap to drive until I put an 80 series rear in it.
8th March 2013, 10:10 AM
Dougal

Quote:

Originally Posted by rick130

I disagree Dougal.

Proper SS braided hose, eg. Earls, Goodridge, Aeroquip -2 and -3 stainless braided teflon hose has less swell under pressure than any standard rubber/fabric reinforced road going brake hose, that's why they are used in aircraft and all motorsport applications.

The fabric braiding in my bike brake lines are kevlar. This is about 50% stiffer on a volume basis than stainless but also gets an anti-chaff cover. I have a goodridge hose set for one of my bikes that I bought about 5 years ago (factory hose too short). I still haven't installed it.
On my bike brakes the lever is firm but I can still squeeze it into the grip. Visually you can see the caliper spread, the lever blade flex and the lever body flex.
Hose flex is such a small factor that I'm not worried about it at all. I am worried about the goodridge hose eating the frame and fork crowns. Yes it has a clear protective cover, but the shimano/grimeca/xsiv brakes did some awful damage back in the day.

On my rangie I get a firm pedal without the booster, but can push another two inches. Flexing the firewall mainly.
The other point, a system without much compliance can be difficult to modulate for some drivers. Stiffening everything up too much results in a lot of over-braking that some drivers can't get their head around. The whole force based or movement based brake response.

Of course if line compliance was the biggest concern, we could drop line pressure by fitting bigger bore MC and caliper pistons.

Quote:

Originally Posted by rick130

I've had them fitted to the Deefer for ten years now.
Rubbed one line through on a radius arm though :angel:

Now have polyester coated hose and plastic spiral wound 'wire' around the outside for better security from 'stuff'.

Ouch. Yes I specced the spiral wire around the extended brake lines I had built for that reason too. I should get read the hose specs off them one day.
8th March 2013, 07:30 PM
rick130

Quote:

Originally Posted by Camo

Yer 1k later. Could just buy HD rover axles for that. I don't get it.

I tried 3 types of driveshafts on mine. I'm not sure a twin DC shaft could work. I had a single DC shaft made and the DC end was at its max already. Would only get worse if you had twin DC. Might be able to get a high angle DC.. not sure. I gave up trying after spending so much money.

Rover HD axles, steering and lockers are cheap these days compared to when I had my GQ conversion done. Can safely put 35's on and not worry about breakage (pending driving style of coarse)

My brakes were mushy.. worse than the rover ones. Didn't really care though. Car was crap to drive until I put an 80 series rear in it.

Yep, and I wouldn't bother either, I like my shaved Sals, just offering options. :D
8th March 2013, 07:46 PM
rick130

Quote:

Originally Posted by Dougal

The fabric braiding in my bike brake lines are kevlar. This is about 50% stiffer on a volume basis than stainless but also gets an anti-chaff cover.
[snip]

Stiffening everything up too much results in a lot of over-braking that some drivers can't get their head around. The whole force based or movement based brake response.

Of course if line compliance was the biggest concern, we could drop line pressure by fitting bigger bore MC and caliper pistons.

Ouch. Yes I specced the spiral wire around the extended brake lines I had built for that reason too. I should get read the hose specs off them one day.

I still use the original hose on my old Hayes MTB stoppers too :D

Aramid coverings (Nomex and Kevlar) are only used for anti-chafe and weight savings on oil hoses, etc in race cars.
All the brake hoses AFAIK are still .040" wall Teflon liner with a HD Stainless braid.
F1/Sports Cars may be using something really trick as their line pressures and the stiffness of everything is so great (even though they aren't allowed to use Beryllium any more)
I've been out of it all way too long to know definitively, but I remember they used limited amounts of flex hose, hard line was run as much as possible.
We just ran SS braided hose everywhere, it was just easier :angel:

Brake modulation was, and I'm guessing is a still a big issue.
I went out to the track once with a car and driver and spent all day swapping out brake pads to get the best combination of bite/modulation/retardation.
Racing is exxy :(

When I lost that hose I didn't pick the wear on the line, and I periodically checked them for stuff like that as I made them so long ago. :angel:
There's barely a mark on the radius arm too, I highly doubt I could pick where it occurred now.

It was a touch over twelve months ago during our yearly rego check/brake test here in NSW and the tester came back in using the handbrake on the Deefer to stop :confused:
He was ashen faced when he walked back into the workshop........
Luckily it hadn't happened to me on an emergency stop out on the road somewhere :eek:

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