looking at my options for brake upgrades, and figured i might as well copy a setup i know works- 12" C4 front brakes with stock rear drums with a 15/16" bore manual master cylinder from a late 70's Chevelle.. i used that setup on my 71 Nova and it was perfect in every way as far as pedal feel and stopping power, and it sure did open up a lot of room under the hood..

i did some looking on my car (86 Camaro), and there isn't a hole on the pedal for a manual master cylinder- but holes are easy to drill.

 

No third gens came with manual brakes. I use an aluminum master cylinder from an S10 that had manual brakes. I have no idea what size the piston is but it works for me. I have disk brakes on all 4 corners and a manually adjusted proportioning valve for the rears.

As for the pedal, you drill a hole 1" higher that the original hole. Since the master cylinder won't be attached to a brake booster, it will sit more level. The higher hole will increase the mechanical advantage of the brake pedal and make the pushrod more inline with the master cylinder pushing straight instead of upward.

The third gen's master cylinder also has the outlet ports on the engine side. Just about every other GM master cylinder has the ports on the fender side so all your lines will need to be switched around. I'm not sure if your 86 will have standard double flare fittings or the metric bubble flare fittings. Metric lines will need adapters to go into that old cast iron master cylinder.

To properly attach a master cylinder directly to the firewall, you should use an adapter plate.

 

that's what i thought.. thanks..