Brakes??????

[Big Blue J-10]

Is there any other upgrades or mods that can be done to improve braking performance besides the Hydro-boost set-up???
Such as better pads roters ect...Or are there any mods that you can do to exsisting rotots????

Adam

[illegalFSJ]

The dual-diaphram booster from a J-20 or late 80s GW is supposed to help a great deal.

[Big Blue J-10]

Is that a direct bolt in or do you have to fab????

Adam

[Big Blue J-10]

also is there any diference in size of the booster????

Adam

[J10/J20 Project]

I have a 83 J20 Booster/Master in my 78 J10 direct bolt in for me.

[napaman]

Better brakes on an fsj? Try this: 1. Use cailpers from a 79-86 Chevy c/k20. These have about a quarter inch bigger piston, which will multiply the current force excerted on the pads by about 15%. 2. Use the pads for the same vehicle. There will be two sets listed in the book. The larger set is what you want. This set has roughly 12% more braking surface. Napa part number is AE7084AM. 3. Replace your rear wheel cylinders with Napa part number 37080. I forget what these are supposed to fit, but the pistons are 1/16" larger. This multiplies the force exerted on the shoes by about 10%, helping to balance the braking with your upgraded front. I realize this stuff isn't exactly cheep, but it can be done in stages as your old parts die or as your funds allow. Lastly, you could try a set of performance rotors(the kind with the holes and/or slots). Napa has those for our rigs, but this becomes BIG money. I hope this helps you. I've done this upgrade to my '89, and it stops much easier. After the TFI upgrade, this should be next on everyone's list.

[Big Blue J-10]

Many thanks all of you!!!!

Adam

[ August 21, 2004, 09:02 PM: Message edited by: Big Blue J-10 ]

[Jlamb]

napaman,

I see what you are trying to achive with larger size cylinders on the corners but I would think that with all that extra room to fill the master cylinder would not be enough to fill the calipers and wheel cylinders.

I do like this idea but feel it has one flaw. The master cylinder needs to be bigger to provide a high and hard brake pedal. It all starts with the "master" and ends at the workers. If you do not have a good master that can keep the other cylinders filled it could make the pedal worse.

Let me give you an example. 1993-1995 Ford E250 and E350s. Have a common problem. Their pedal can sink. The problem is that the master cylinder bore is to small to fill the front dual piston calipers. The system will then equalize and cause a sinking problem. The fix for this problem is to install an updated master cylinder that has a 1 5/16" bore (old style is 1 1/8" bore) This will bring the pedal high and hard.

Do you know if napa has a bigger bore master cylinder that will bolt on to a FSJ?

[napaman]

Justin, The pedal hieght decreases by no more than 3/8 to 1/2 inch. The system works fine. As a matter of fact, the part number for the fsj master cylinder is the same for the 79-86 c/k20 truck that the calipers are used on. (I checked that before doing mine, thinking the same thing you were.) The new wheel cyls are also the same size. To notice the increace in pedal travel, you have to measure it. It's that small.

[Jlamb]

Good to know napaman, but is there are larger master out there that will bolt on? I only ask because I would like to get a firmer pedal and all my hoses, calipers, wheel cylinders, and the current master is good.

[JeepsAndGuns]

I heard that the chevy one ton MS bolts right on. But I havent done it so I'm not for shure.

[bmearl4]

As far as cheap upgrades, look at the pad material. Softer equates to better grip. Be warned, like tires, better grip equals less service-life.
Another change would be an upgrade to all braided stainless steel lines.
If anything, perhaps pull your stock cylinders and calipers to rebuild them. Yes, its sounds silly if they aren't broke, but new rings and freshly honed bores will help quite a bit.
Bleeding out all the old fluid and adding new (if the old fluid is really old and black)will help too.
Echoing Jlamb, you can only fudge the size difference a little. Carmakers only made the parts for the vehicles as big as the rest needed to rely on. Nothing more, costs money you know. So swapping in parts from other vehicles to work with existing is high wire act, mistakes have painful and expensive consequences (and will occasionally require a mop).
So, with that cheery thought out there, good luck.