Technical Master Cylinder choice

Ok here is what I have 63 C10 front disc(80 Camaro Calipers) rears are stock C10 drums with 1" bore wheel cylinders, I will be changing to a 31/32 rear wheel cyl
MC is a 68 Corvette with a 1" bore. brakes are bled well(I think)
I have a soft pedal. ***uming that it IS in fact bled properly and I want a little harder pedal, would a 1-1/8 mc work better. There is a corvette MC with that configuration.

 

Is this a manual or boosted system?

 

You are correct the bore is too small. The 1-1/8" bore master should work better. What size master cylinder was used for 80 Camaro? Does your truck use a booster? The rear wheel cylinders will help a bit if they don't cause the rear to lock up. What was the original master cylinder size?

 

Manual brakes, it looks like the camaro uses a 1" bore. The original was a drum/drum from a 67 C10 and was 1" bore. Oh, and thanks for the fast responses

 

From my understanding, and I am not the smartest out there, since your brakes are manual you definitely don't want to go any bigger than a 1" bore. If you're convinced the problem lies with the bore size of the master cylinder, go to a 7/8" bore from a mustang(?).

 

You never mentioned a proportion valve, I believe that may be where your problem lies. A factory Camaro should be sufficient.

 

Also make sure that you have the integrated master or in line residual pressure valves required. They have an effect on brake pedal feel as well.

 

I got the brake kit from POL, I am going to order the matching combination valve GM 172-1353, The rpv is built in

 

Curious why are you changing the wheel cylinder from 1"?
The 1" master should work OK with your brakes. The 1 1/8" will require more pedal efforts and is usually used with power ***ist, unless you have a lot a room for a low manual pedal ratio greater than 6:1.
Corvette dual masters were all disc/disc and never used an internal residual, so a 10 lb inline would be required with your rear drums.

 

According to my trusty Wagner brake bible the 80 Camaro had 2 15/16" front , 15/16" rear with a 1" manual bore, power was 1 1/8". Your 1" bore SHOULD get you a decent pedal.

 

I am going to keep the 1" MC do you think a 10# RPV for the rear drums will suffice as opposed to the combination valve?

 

You don't need the RPV with the MC above the wheel cylinders.

 

I am not sure but we're 80 calipers the metric ones ( low drag). You might need a quick take up master cylinder. I believe early s10 trucks had a manual brake option.

 

Most drum brakes up to the'70s really do need residuals, and later drum brakes will benefit also.