Hello All,

I'm getting ready to install the C4 rear brake calipers. But need some help. I purchased the C4 adaptors from Chris. Which will require (8) 12M 1.75 x 20mm Hex Head Cap Screws (rear) (Still Need to Purchase)

Do I need tap the existing Fiero mounting holes to M12?

Do I need to grind away any tabs\ears from the existing brakets? See Pics below.

Do I need to purchase longer wheel studs?


I purchased set of rebuilt rear C4 calipers with adaptors. I have a set of new 12" corvette rotors that came with the car when I purchased it. While test fitting, I noticed that caliper opening is 24.5MM where as the rotor thick ness is 26.32MM.

Rotor numbers are Centric 127.62062R and Centric 127.62061L from what I can tell these are C5 Rear rotors.

C5 Rotor Info

Which sucks...

I have a few options now, purchase new C4 rotors and have them drilled to 5X100. I can get a set of drilled and slotted Power Stop Rotors at RockAuto for $100 for the pair.

or

Does anyone sell a rear C5 rotor adaptors?

The car also came with a new set of C5 rear calipers. I know that I would lose my Emergency brake going this route. But the car so came with after market rear E brakes.

[This message has been edited by str8maxn (edited 01-16-2022).]

You live in a state where there are very strict vehicle inspection laws. Eliminating the eBrake will probably make your car fail inspection. If you are going through with this brake swap anyway you must give also thought to using a compatible master cylinder with the capacity to support the caliper wheel cylinders that you will use

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quote Originally posted by Dennis LaGrua: You live in a state where there are very strict vehicle inspection laws. Eliminating the eBrake will probably make your car fail inspection. If you are going through with this brake swap anyway you must give also thought to using a compatible master cylinder with the capacity to support the caliper wheel cylinders that you will use

Dennis, CA doesn't do a safety inspection. As long as the car ain't polluting and hasn't had an engine change they don't worry here.

quote Originally posted by reinhart: Dennis, CA doesn't do a safety inspection. As long as the car ain't polluting and hasn't had an engine change they don't worry here.

Yep .. only need to work about smog in Cali.

Do you know who made the adapters? Some of the swaps work only with a specific rotor like non heavy duty of that year.