Courier Brake Line Question

[Theorangetiger]

I'm fitting Wilwoods all around with a Courier master cylinder and of course, all new brake lines. On the master cylinder, which line feeds the fronts and which feeds the rears? I read an account here regarding fitting a Nissan mc and they crossover - front line feeds rear brakes. Is it the same with the Courier unit or does it matter?

 

[boss-tiger]

usually the larger brake master cyl reservoir is for the front brakes as a best guess - I used a Courier back in the 80's and worked well using stock Sunbeam front disc's and rear disc swap from another Datsun (back in those good old days - ha). FYI, banjo fittings at master cyl will simplify install and look cleaner IMO.

 

[Theorangetiger]

Thanks. The Courier unit I bought has equal sized reservoir for each circuit and I modified it with larger independent reservoirs.
I figure with the same size bore and the same amount of movement, the output must be identical. Thanks for the tip on the banjo fittings. That's the only part of the plumbing I hadn't really mapped out.

 

[boss-tiger]

I would bet there is a difference, but unknown. FYI, I am out of town now but believe I may still have an old original Courier brake master from 80's. From memory it had a single large rectangular reservoir (internal divided) which may help answer your question. FYI I will be able to look for it next weekend. Banjo fittings are much easier to plumb brake lines to and more forgiving with angles. Most people these days are using the Datsun Z brake master (which is what I am using now and it works great FYI). Also suggest you look into the 6:1 pedal upgrade (yep, it's easy to spend spend spend on these cars).

 

[0neoffive]

I would bet there is a difference, but unknown. FYI, I am out of town now but believe I may still have an old original Courier brake master from 80's. From memory it had a single large rectangular reservoir (internal divided) which may help answer your question. FYI I will be able to look for it next weekend. Banjo fittings are much easier to plumb brake lines to and more forgiving with angles. Most people these days are using the Datsun Z brake master (which is what I am using now and it works great FYI). Also suggest you look into the 6:1 pedal upgrade (yep, it's easy to spend spend spend on these cars).

The rear is the front output .

 

[Theorangetiger]

Doing a little internet reading, other than the larger reservoir point, it seems the difference in functionality is most pre-ABS systems want the rear brakes working just slightly before the fronts because rear lockup is preferable to front. So the fluid flow to the rears happens milliseconds before the fronts. A proportioning valve will reduce the rear lockup if it is excessive.
I still wonder about the front line to rear brakes logic when it easily could have been done the more logical front to front if the mc was designed that way.
I've given this too much thought but did get a satisfactory answer and will plumb them from front outlet to rear brakes.

 

[Hoghead]

The rear is the front output .

Brakes are my project over the next couple of weeks and also have a courier MC.
Plumbing the rear to the front brakes is counter intuitive

Theredtiger reports that the bore and stroke are the same. Is that the case, and if so why does it matter which output runs where?

 

[Austin Healer]

Doing a little internet reading, other than the larger reservoir point, it seems the difference in functionality is most pre-ABS systems want the rear brakes working just slightly before the fronts because rear lockup is preferable to front. So the fluid flow to the rears happens milliseconds before the fronts. A proportioning valve will reduce the rear lockup if it is excessive.
I still wonder about the front line to rear brakes logic when it easily could have been done the more logical front to front if the mc was designed that way.
I've given this too much thought but did get a satisfactory answer and will plumb them from front outlet to rear brakes.

that seems counter intuitive as in all cars the bias is on the front wheels under braking... the front brakes do the majority of the work. this is because the majority of the weight is in the front in the vast majority of cars..

 

[0neoffive]

that seems counter intuitive as in all cars the bias is on the front wheels under braking... the front brakes do the majority of the work. this is because the majority of the weight is in the front in the vast majority of cars..

One more time. The rear goes to the front. Go look at a Currier.

 

[Theorangetiger]

that seems counter intuitive as in all cars the bias is on the front wheels under braking... the front brakes do the majority of the work. this is because the majority of the weight is in the front in the vast majority of cars..

I agree that the front brakes do the majority of the braking, mostly because all of the momentum is going to the front of the car. We all know that from changing pads. But as far as either the fronts or rears locking up first, rears is preferable because the car will skid but not spin out so systems are engineered this way.

 

[Austin Healer]

One more time. The rear goes to the front. Go look at a Currier.

I agree completely! The port closest to the firewall is for the front brakes, the one towards the front of the car is for the rear circuit... every dual circuit master cylinder I have ever seen in 40 years of wrenching is this way. What I meant by "counter-intuitive" was, it's the FRONT brakes that get activated first as they are doing the majority of the work.. engaging the rear brakes first would adversely affect both the braking performance and the handling/directional stability of the car. (severe understeer under rear wheel locking) This is due to the changes in weight bias under braking. under braking the weight gets transferred to the front of the car as a result of momentum... the less the loading over the rear of the car, the less effective the rear brakes are. it's just physics...

 

[boss-tiger]

Sorry this took so long, turns out this Courier brake master cyl was in the storage garage that I usually do not store Tiger parts in - it's always something. I agree port closest to firewall woudl be for front but FYI there are no markings such as F or R on the master cyl pictured. I know the datsun master cyl I have used have front port near firewall.

 

[Austin Healer]

Sorry this took so long, turns out this Courier brake master cyl was in the storage garage that I usually do not store Tiger parts in - it's always something. I agree port closest to firewall woudl be for front but FYI there are no markings such as F or R on the master cyl pictured. I know the datsun master cyl I have used have front port near firewall.

View attachment 15589

View attachment 15590

the port next to the firewall is always for the front brakes

 

[Hoghead]

the port next to the firewall is always for the front brakes

the port next to the firewall is always for the front brakes

Plumbed mine like that yesterday............