Just Purchased #2096, a 71 that has been hidden away, the subject of a full
retoration by the previous owner of over a twenty year period. The car has
22,000 original miles. Just a few items to sort out. The most important is
getting the car to stop. The brake pedal is very hard ( read stand on the
pedal with both feet) and brakes are marginal to frightening at best. I have
bled everything twice with no improovement. What would be your step by step
to sorting this out.

Fred Cook
Original Post
Pull up a chair- brakes are the second-most modified system on a Pantera (after tire sizes). First, if they haven't been changed, the 29-yr-old rubber brake hoses should be instantly replaced, either by new OEMs, or by Aeroquip braided-stainless. Second, the OEM non-adjustable proportioning valve should be discarded; it routes full pressure to the rear brakes and drops pressure to the fronts- where most braking is done. It is designed for bias-ply 185-70x 15 fronts and 205-70x15 rears. Either use a manual proportioning valve, or no valve at all. Be careful in rerouting this plumbing- the stock setup is a dual circuit so the frt & rears are separate; combining them will remove a safety feature. Third, there is a 'brake warning light shuttle valve' under the power brake unit. This ass'y has a brass slider inside that moves with brake fluid flow and if the pads are worn too far, turns on the brake warning light on the dash. The slider sometimes gets stuck at one end of its travel and effectively cuts off either the front or rear brakes! This can happen during bleeding, too. To fix this, either use an air compressor to recenter the slider, or disassemble the unit and clean the brass slider. Finally, you may want to look at the brake pads. If the pads were not broken in properly, they may have glazed, which will form a gas bearing between the pads & rotor. If so, scotch-brite the pad surfaces and rotors.
I agree with the other responses. The first thing to do is make sure everything is moving freely and that your lines are replaced. This will sound obvious, but is yur vacuum booster line hooked up? If not, your engine wouldn't be running properly unless there is somehow a clog or kink in the line. But even if you restore your brake system to factory perfect, it's still a marginal brake system at best. There are many brake upgrades from Hall's, pantera international, and many others. I'll choose not to endorse any particular brand. If, however, you wish to keep your car as stock as possible, you can make great improvements without a lot of money. The usual pantera outlets will sell booster and master cylinder sets in the $600 range. These will greatly reduce peddle pressure. Next, get rid of your stock pads. I'm sure you've found out that they're hard as a diamond and squeal louder than my newborn son. I'm very satisfied with the porterfield peformance street pad (they make a race pad, but they produce more dust and noise). These can be obtained through several outlets (do an internet search on porterfield brakes). Front and rears can be purchased for around $200-$250. Hope this and the other responses help out.
Thanks for all the advice on the brake system on #2097. Here's an update.

1. Primary cause of the braking problem was that the vacuum booster was toast. Replaced with new booster and master cylinder combo.

2. Old brake hoses were soft and in marginal condition. These are being replaced with braided stainless steel lines.

3. In the process of removing the hoses, I noticed corrosion on fittings and sediment in the bottom loop of the hard lines. All hard lines and fittings will be replaced with new 3/16" lines.

4.The brake warning light manifold was in good condition. The shuttle inside and the warning switch function properly. I plan to retain this fitting as it simplifies the plumbing, provides a safety feature and keeps things a bit closer to a stock look.

5. Removed the old porportioning valve on the front lines. It did not appear to be defective, but so much negitive discussion about this fitting convinced me to replace it with a simple "T" connection to the front wheel lines. Does anyone have a pro or con on this direct set-up verses an adjustable valve?

6. At this point I have not decided on the necessity of 2psi residual check valves in forward and rear lines. Again, any comments would be appreciated.

So far, finding all the required fittings and adapters at the local speed shop has been fairly easy. In any event, time is on my side as the car is on jacks in the garage and it's getting very cold in the Boston area.

Thanks again: Fred Cook
2nd update.

1. All the brake lines are out of the car. There was serious corrosion on the lines in where the plastic split hoses were used to prevent chafe in the clamps. If you own a Pantera with original lines I suggest you take a look as this could kill you!

2. I added a porportioning valve to the rear lines after the shuttle valve. I have yet to test the wisdom of this $85 investment, but it's the way most race cars are set up. Even if not required now it's there if I change the wheels and tires in the future.

3. I retained the old shuttle valve but the differential warning light switch is now leaking. What a pain in the....Anybody know where I can get new "O" rings and seals?

4. It snowed here ( South of Boston ) yesterday and the roads are covered with salt and the car is up on jacks for the next three months, so there is all kinds of time to solve my problems.

Best to all. Fred Cook #2096
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