Manual master cylinder
 

I'm sure this topic has been beat to death, but I cant find the answer I am looking for. I want to use a manual master cylinder and stock 98 Camaro front and rear disc brakes. So far all I have found is guys with drag brakes front and rear run the 1.125 bore and guys with stock fronts and race rears are using 1.032 bore master. What master are guys with stock front and rear brakes using? Anyone using the 1.032 bore master cylinder with stock disc brakes?

I have 6 piston Wilwood brakes front and stock LS1 F-body in back, and I have a 1" bore manual master. It stops the car repeatedly (road race) without issue.

I would hope it stops the car repeatedly. I think the original poster is asking how hard the pedal is, how much pedal travel, etc.

That is correct, I don't want to buy the 1.032 master and have the car not stop and have to go looking for a 1.00 bore master. 1.032 and 1.125 bore master are the only 2 I've found for a 4th gen F-body manual brake conversion kits. Neither of them say they work with stock disc brakes front and rear brakes.

It's harder than the power brakes were, but it gets the job done. By "repeatedly" I meant that it will do several 20-25 minute sessions a day with a lot of 130+ to 40ish slowdowns and not fade or make my leg tired. In my case, pedal travel is dictated by the master cylinder - it bottoms out on the master before the pedal hits the floor, and the brakes lock just before I get that far. My car weighs @2950 without me in it.

For giggles, I checked Rock Auto, and 4th gens appear to all have a 1" bore from the factory. So unless you have a shorter bore in your manual master (shorter pedal travel), the 1.032 will be roughly similar to stock. It will probably feel a bit harder, but it will move the same volume of brake fluid. The 1.125 will feel much harder than the smaller bores, but it will also move more fluid and would have a better safety margin.

Another thing to consider: look at using a really aggressive brake pad.

What master are you using? Wilwood?

yes, I have a Wilwood master cylinder

Well, which one for stock brakes and lines?

I used Wilwood PN 260-8555 for mine. But honestly, I'd call them and have them suggest something. While I have LS1 brakes and bigger calipers on front and I'd have no problem suggesting it to another 2nd gen guy, RobZ28 has a forth gen and unforeseen things might be different, like bolt pattern on the firewall, firewall angle or master cylinder bore depth.

I used an FJ Smith Race Cars kit on mine. Comes with the master cylinder, mounting plate, and instructions showing where to drill the brake pedal to correct the ratio. Been using it for about six years now. Works great. He is located know Canada.

Damn Ed, where you been?
Haven't heard from you lately.

I have used our kit with factory brakes. It works but don't expect a power brake like pedal. A lot more pedal effort is needed to achieve the same effect as with power brakes or drag brakes.

What size bore is your's?

Don't really see too much interesting here anymore.

Are you using that master cylinder kit with stock F-body brakes or aftermarket drag brakes?

Pretty sure it still had brakes to begin with. Six or eight years ago.
Don't remember the bore size. I would ask them about it.

You will need to change the pedal ratio like Ed said for best results. According to the strange website the 1.032 bore ratio is 5.5:1, and the 1.125 bore ratio is 6.5:1. Just do the quick math and re-drill the pedal. If i remember correctly, its about an inch off the existing hole. I can easily build 1200 lbs brake pressure without any problems.

Still don't know which bore to get for stock brakes.

Stock bore is 1". That works fine for stock brakes. Unless you have bigger calipers than stock OR the aftermarket master has a shorter bore/pedal travel, you don't need a bigger bore. However, I strongly advise talking to Wilwood or FJ Smith and picking their brains a bit. We're all just guys on a forum. They "live" in the performance brake world.

I called and talked to the guys at FJ Smith Race Cars about their manual master kit, they use the 1.032 master and said they have people using that master with stock disc brakes without any complaints. Steve at Burkhart has also said they have used their master conversion kit with stock brakes. I'm going to try the 1.032 master and hope for the best.