fj40 disc brake system theory (1 Viewer)

[randle]

this may seem like a crazy idea, or maybe i just haven't heard it before.

splash guards are made to keep water ( to a certain extent) off of brake friction surfaces.

with soft suspensions, 4 wheel disc brake systems commonly lock up the rear wheels before the front during hard braking/ low traction situations.

what if you allowed the rear brakes to more easily lose friction and gain traction on wet roads?

you could do it by removing the spalsh guards on the rear axle and leaving them on the front right?

i would guess the effect to be most reliable on wet freeways, a great time to not lock up the rear end .

what do you all think?

ridiculous?

 

[projektdotnet]

I thought that was the whole point of a proportioning valve

 

[randle]

good proprtioning valves are ride height sensitive. the ones used for cruisers are not, they are set to a static ratio right?

 

[projektdotnet]

IIRC yes they are there to regulate how much pressure is applied in the rear period

 

[randle]

i think i'm going to chalk it up to late saturday night brainiacism, as opposed to late sunday night realism

 

[agent orange]

good proprtioning valves are ride height sensitive. the ones used for cruisers are not, they are set to a static ratio right?

62s and 80s have load sensing proportioning valves. That is a good thing when stock, and an irritation when lifted.

 

[mr_manny]

I am only running guards on the front, and it does not help.

Other then adding an adjustable valve in the rear, has anyone tried adding 2lb residual pressure valves onto the front-circuit ONLY?

This should improve the responsiveness of the front...balancing the system?

 

[randle]

i thought it might be too simple to work. even if it did, it would only be in very specific circumstances.

i think (speculation) the real reason that some cruisers have rear brake lockup problems and others don't is due to weight transfer. there are so many differences in suspension setup, ride height and vehicle use. you guys that have problems with this: do you have a lot of nose dive upon hard braking?

i'm going to try to minimize nose dive while still having a nice cushy suspension if at all possible. maybe use adjustable or stiff shocks for city driving/rallyin' along with no shackle reversal.

 

[peesalot]

Manny, that is what I am runnin. I still have drum in the back but they stop as well as a disc. I left the res. valve in when I put the chevy brakes on and they work great , save for I used a 1/2 ton rotor where I shoulda used a 3/4 ton 6 lug. The pads just have to be modified slightly.

 

[Mark W]

The guards tend to trap mud and silt and other debris from sloppy trails in th brakes. Small rocks too. Lose them. They don't do anything positive in the real world.


Mark...

 

[projektdotnet]

Glad I diched mine while converting

I get major nose dive when braking as asked above so I have learned how far I can go before I gotta start pumping and even with the fronts putting lots on the ground for stopping I can still lock up all 4 wheels

 

[randle]

yeah, i was wondering if they would trap crap in there.

i am officially losing all of them,
thanks

 

[agent orange]

Mark, im assuming you arent referring to drum brakes though right?

 

[Mark W]

Splash guards on rear drums?

When you run in sloppy environments where the wheels are down in the mud and slop a lot, you do occasionally get small rocks/pebbles and commonly get mud and silt inside the rear drums. But it's not like you can do away with the backing plates to keep it from getting trapped. Unless of course you do away with the drums entirely and install discs.


Mark...