I have also installed Corvette C4 calipers and rotors into my 1987 GT.
Both Fiero and C4 use similar configurations for their handbrakes but cable lengths and style of end links are different. The Fiero’s factory handbrake cabling cannot be directly connected to the handbrake levers on the C4 rear calipers.
There are several documented solutions but I just decided to go my own way. I adapted the cable system from the C4 Corvette.
First, I pulled the parking brake cabling - from handbrake lever to calipers - from a 1987 Corvette at a junkyard. The cables are also available new and are inexpensive (e.g. Rockauto currently has them).
There are three cables:
• One cable that runs from the handbrake lever to the center of the car rearward of the engine. I reused this factory Fiero cable and did not modify it.
• Another cable connects to this cable and goes to the passenger side rear brake caliper. I removed the factory Fiero cable and installed the C4 cable after shortening the outer sheath about 8 cm.
• The third, driver’s side, cable is weird. The inner cable (conceptually) stays stationary while the system moves the outer cable to cause the inner cable to tighten. I shortened the inner cable about 5 cm by wrapping it around a cable clamp.
• I also removed the tightly wound springs around the C4 inner cables at both the calipers.
The last thing I did was remove the connector joining first and second cables and replaced it with a turnbuckle. This allowed me to fine tune the pull on the calipers so that both brakes clamped as fully as they can.
I consider the installation to be quite elegant. The thing I like is that the C4 outer cables (the sheaths) are flexible but stay in place when bent. I was able to shape them to make a smooth curve upward to the calipers thereby reducing friction in the cabling.
This is my first technical post on PFF so forgive me if this newbie is posting a solution that has been done many times before, or if there are better, simpler solutions.
This is what the stock C4 handbrake cable system looks like:
This is the passenger side C4 handbrake cable modified for installation on the Fiero. Note the bend in the sheathing near the caliper end and note the different end link than what Fiero uses. Note also the 5 cm of outer sheathing that I will remove.:
This photo shows the driver's side cable below the reversed passenger side cable. I bent the outer sheathing of the driver's side similar to what I did to the passenger's side and also shortened the driver side inner cable by wrapping it around a cable clamp. Unfortunately, I did not take a photo.
To adjust the length of the cables so that they pull both caliper levers uniformly, I installed a turnbuckle between the two sides of the car. Using the turnbuckle, I adjusted the passenger's side until there was no slack, then I used the C4 factory adjuster to take the slack out of the driver's side cable.
Here is a photo of a C4 cable routing to the brake caliper. It stays nice and high to the frame and does not have sharp bends.