about to go disk fronts in the 40 to power or not to power???

[dohcdelsol93]

current plans

1976 fj40 disk axles (already have)

1978 dual circuit master cylinder (already have)

4 runner 4 piston calipers (already have)

master cylinder adapter to early 40 tub (already have)

25 ft of new brake lines(already have)

2 brand new 76 fj40 disk rotors (already have)

also already have extended SS braided brake lines



Keeping drums in back

planning on ordering a prop valve for rear and adding a 10 lbs residual valve

and putting a 2lbs residual valve to front with no prop valve.


I'll buy some 10mmx24 thread stock to make a custom brake push rod.



But while i have her apart for a few hours should i add power brakes.

IIRC a mini truck power brake booster of around 1980 will fit my new dual circuit master.

I've heard many people say manual disk brakes are fine but also heard if you go disks you need to go power.


What experience have you guys had?

As many of you know i will be towing a lot of boats with this rig.

My bass boat really pushed my finely adjusted drum brakes.

My sail boat will be of about equal weight but longer.

I've towed boats with short wheel base vehicles for years, about 10 with an bronco II and with the ex wife's liberty.

I'm thnking...build an adapter/spacer and power her. But if it doesn't make much difference i might as well not worry about it.

This week i plan on ordering a 2lbs residual valve for front disks

 

[Trollhole]

Knowing your luck I'd go power and make sure your parking brake works really good.

 

[dohcdelsol93]

I love power brakes but the only thing that worries me is stalling out and needing brakes. Wheeling is not much of an issue because I don't go often but when pulling a boat out of a steep. Ramp with seasonal low water could be dangerous. All swb. Vehicles I have previously owned were automatic

 

[BELMONT148]

Brakes still work without power.

 

[Southeast Overland]

Brakes still work without power.

Not nearly as well. I had a stalling problem in my Pig (now fixed) and when you lost power your brakes suck. Especially when trying to stop a Pig from about 45 mph.

 

[BELMONT148]

I meant on a trail or a boat ramp, not going 45 mph.

The advantages of power far excedes the off chance of a high speed power loss. IMO

Jeremy

 

[Southeast Overland]

I meant on a trail or a boat ramp, not going 45 mph.

The advantages of power far excedes the off chance of a high speed power loss. IMO

Jeremy

? You are in a good mood.

 

[BELMONT148]

I'm in a great mood. Just got notice that the Tacoma lift shipped and looking at how I am going to fit 35" General Grabber ET's in the wheel wells. Body mount chop comes to mind.


Didn't mean to come off rude. Let's all hold hands and a take a deep breath.

Getting siced for URE and some snow wheeling this winter.

Jeremy

 

[Trollhole]

I love power brakes but the only thing that worries me is stalling out and needing brakes. Wheeling is not much of an issue because I don't go often but when pulling a boat out of a steep. Ramp with seasonal low water could be dangerous. All swb. Vehicles I have previously owned were automatic

Should have never gotten a 40 if you were planning on towing a boat or relying on brakes.

 

[dohcdelsol93]

If my bronco 2 could pull a boat I can get the40 to pull it well. Power brakes suck when you lose power on a steep incline with a boat even in an f250. If non power brakes will be better than the drums I have now is my question

 

[Trollhole]

If you lose power and get hit by a nuclear bomb then yes non power brakes are better.


There is a reason why non power brakes were dropped by all manufacturers in the early 70's.

 

[dohcdelsol93]

Have any. Of you driven a disk brake converted fj40 with manual brakes? If so how did it stop comparedall drums.

 

[BELMONT148]

Never tried it here. I say do it. Just make sure you get a good dual master cylinder. The old chevy corvette cylinders come to mind. They had disc brakes without a booster back in the day. I hear the master cylinder takes a lot of leg work out of the braking.

Like this http://compare.ebay.com/like/270631499640?var=lv&ltyp=AllFixedPriceItemTypes&var=sbar&_lwgsi=y


Jeremy

 

[Trollhole]

Have any. Of you driven a disk brake converted fj40 with manual brakes? If so how did it stop comparedall drums.

Cluck has this setup.

 

[dohcdelsol93]

my 4 wheel drums work fine after doing a hell of a lot of work to them.

I've got a new master cylinder (single circuit)

new wheel cylinders in back and i keep the adjusted regularly.

However it lacks stopping power when towing.

With disk brakes up front, 4 piston calipers in front to be exact i'm hoping for more braking power.

The dual circuit master cylinder is for saftey. If a wheel cyinder was to give i still have braking power.

The corvette master is dual circuit but IIRC still has only one resevrior meaning that if you lose brake fluid in the rear you will eventually lose it in front. And it lacks a clear container where it's easy to check level.

I have a few fiero dual circuit master cylinders and power boosters laying around. I'll pull one and keep it in case i still need more braking power. These were also made for rear drum/front disks and are small in size because of the small front compartment given in the front of the body.

Guess i'll document as i go!!!

 

[CruisinTiger]

I love my Corvette MC....you just have to fab up a simple bracket that goes from a 3bolt MC to the 4 bolt firewall....its on mud...when I did mine I actually had the guy make one for me cause I don't have a welded....but I have had zero problems out of the setup.

 

[Trollhole]

I love my Corvette MC....you just have to fab up a simple bracket that goes from a 3bolt MC to the 4 bolt firewall....its on mud...when I did mine I actually had the guy make one for me cause I don't have a welded....but I have had zero problems out of the setup while it's been sitting in the back yard for the past 3 years.

Fixed it for you chuck.


And Josh it sounds like your dead set on using a non boosted system. Make sure to post up when you will be on the road so I can make sure I'm off.

 

[dohcdelsol93]

Fixed it for you chuck.


And Josh it sounds like your dead set on using a non boosted system. Make sure to post up when you will be on the road so I can make sure I'm off.

my 40 has had a non boosted system since 1967. No issues as of yet....well...no issues since i got it. When i got the rig it was truely a death trap!!!! Was scary to have to pump the brakes to stop.


While i'm at my parents place fabing up a mounting bracket to install the one of my long jump seats as a forward facing foldable rear bench seat i may fab up up spacer/adapter to hook my GM master/booster up to my firewall.

If i put her together and don't like the brake pressure it will take half an hour to remove the LC dual circuit master and install the GM master/booster.

I'm obviously not going to drive myself/family around in something unsafe.

Even on the old T/birds/muscle cars my shop builds carbs/engines for they have over 100K in the vehcile.

And they will have over 500 hp with 4 wheel drum brakes. And they stop on a dime.

ONly they are self adjusting. and down tow