Reply to "Brake Upgrade: Done, but Bugs to Work Out"

Scott,

Since your braking imbalance is side-to-side, as opposed to front-to-rear, I suspect you have a maintenance issue rather than a parts selection issue. A piece of "crap" in a brake line can create some serious problems! You could also have multiple problems. A piece of "crap" blocking the left front brake line and a front-to-rear brake imbalance (too much braking at the front) would create the exact problem you're experiencing.

As Jan suggested, it could also be a corner weighting issue but your problem seems to be too severe for that to be the cause. It's also possible that the shuttle valve and pressure reducing valve are incompatible with your new front calipers but that would not explain your side-to-side imbalance.

Are you sure it's your brake pad wear warning light that's on, rather than the emergency brake/shuttle valve warning light? If so, it's a pretty simple circuit, so finding the cause shouldn't be too difficult. I'm not too familiar with this circuit in the Pantera but with many cars, the brake pad warning light illuminates when the circuit is broken as opposed to being completed.

As a general comment, in putting larger than stock calipers on the front of the car only, you've made the front to rear brake balance worse than on a stock Pantera. If you really want to improve the car's braking, you'll need to install larger calipers on the rear as well. At that point, you'll probably require a larger master cylinder, removal of the pressure reducing valve in the front line and the installation of a proportioning valve in the rear line. When it comes to brakes, balance is the single most important factor, so you shouldn't upgrade one end without upgrading the other (IMO).

Call SACC and they'll help you out. Just make sure you know the sizes of the pistons in your new front calipers before you call.