I recently purchased a 85 GT with a hard pedal and assumed no vacuum to the booster , but I don't know where the supply is located in the engine compartment .Can anyone help with some info .

Center of the front firewall in the engine compartment. it runs through the console to the front.

Thanks for the info , as usual for a 31 year old car it has a few mods and rearranged lines .I have one large metal line by the air cleaner that is not hooked up that I'm trying to figure out as well .

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[This message has been edited by tshark (edited 09-08-2018).]

quote Originally posted by Lafiero357: I have one large metal line by the air cleaner that is not hooked up that I'm trying to figure out ... ... vacuum to the booster... I don't know where the supply is located in the engine compartment .

That metal line originally connected the valve valve cover to air cleaner.
(part of PCV system) It was disconnected during recall (new pipe installed).
See here: https://www.fiero.nl/forum/Forum2/HTML/137873.html

The brake vacuum line is connected to the upper intake manifold near the thermostat housing.
It runs between runners of the middle intake above the rear valve cover and connects to a hose from the firewall.
A metal tube then runs through the car to the front firewall where it connects to the booster.



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[This message has been edited by fierosound (edited 05-01-2016).]

Thanks guys , I found both lines . The vacuum line for the brake booster was hooked up and functioning properly , while the other line was disconnected at both ends . I guess they just left it there after the recall you mentioned . This site is invaluable for people needing info on Fieros .

quote Originally posted by Lafiero357: I recently purchased a 85 GT with a hard pedal ....

Consider yourself lucky... Most Fieros have a soft pedal and the owners try everything they can think of to firm it up. The Stock Fiero brakes when functioning 100% are barely adequate by today's standards. Most of them are not functioning 100% at this point due to worn out parts and are scary dangerous. Calipers are notorious for going bad due to corrosion, flex lines bulge out and can fail catastrophically, brake booster leaks, and the emergency brake almost never works, (I've had all these happen to me). What I usually do it replace everything except the metal lines.

[This message has been edited by jscott1 (edited 05-02-2016).]

quote Originally posted by jscott1: Consider yourself lucky... Most Fieros have a soft pedal and the owners try everything they can think of to firm it up. The Stock Fiero brakes when functioning 100% are barely adequate by today's standards. Most of them are not functioning 100% at this point due to worn out parts and are scary dangerous. Calipers are notorious for going bad due to corrosion, flex lines bulge out and can fail catastrophically, brake booster leaks, and the emergency brake almost never works, (I've had all these happen to me). What I usually do it replace everything except the metal lines.

My brake pedal is quite soft ('85 duke auto) but I can lock up the wheels anytime. Are my brakes "good" if I can lock up the wheels or are there more requirements for brakes to be good? The braking distance is not so great without locking up.

It sounds like your tires may be a bit hard and slick, not holding the road. Some tires get so hard they are almost like hard plastic!

quote Originally posted by cebix: My brake pedal is quite soft ('85 duke auto) but I can lock up the wheels anytime. Are my brakes "good" if I can lock up the wheels or are there more requirements for brakes to be good? The braking distance is not so great without locking up.

quote Originally posted by White84SE: It sounds like your tires may be a bit hard and slick, not holding the road. Some tires get so hard they are almost like hard plastic!

That's possible. The tires I bought new though and they have only 4 years and have seen less than 10000 miles.

quote Originally posted by cebix: My brake pedal is quite soft ('85 duke auto) but I can lock up the wheels anytime. Are my brakes "good" if I can lock up the wheels or are there more requirements for brakes to be good? The braking distance is not so great without locking up.

From a physics standpoint locking up is not the best case. What you want is to get just to the point of locking up but continuing to roll. Once you lock up you lose control. A front wheel can't steer unless it's rolling. A rear wheel not spinning is going to want to swap ends, neither is a good scenario.

Most likley cause of a soft pedal is air in the brake line. A good bleeding might help, but if a bad seal somewhere is letting in air the bleed isn't going to last long. Throwing parts at a car is usually not the best solution, but on a 30+ year old car I go and replace all the wear items if I can, (new master, new calipers, new flexlines, new pads, new rotors, etc).