Brake master sizing

[jerome]

I'm under time pressure to order stuff, and just don't have the time or energy to research this stuff on my own, hopefully you guys will have the answers to this.

1982 S10, roughly 3000 lbs and just a tad forward of 50/50 weight distribution (lots of redistribution).

Front: ats spindles with OEM C5 disc brakes



Rear: Ford 8.8 with OEM Explorer disc brakes, no clue...

I will be using a manual wilwood pedal setup
http://www.wilwood.com/Products/005-...dual/index.asp
6.25:1 pedal ratio

Questions:
1. What master sizes (front & rear)? I've heard 1" for front? rear no clue.
2. What size lines, I'm planning on bending hard line (front and back), and what kind of flare to use. 3/16 i've heard?
3. What flexy front brake hoses (rubber vs. ss) and for what application...stock c5 vette?

Again, I apologize for not researching and finding the answers myself, I was just hoping someone had experience with this kind of stuff, so that I could call up wilwood tomorrow and confirm that they recommended the right sizes, I've heard stories about how bad they are.

Thanks,
Jerome

[35spline]

To calculate piston area, use the following equation: πr2 (3.14159 x radius squared.)
·If using calipers with more than one piston, calculate the area for each piston, and then add the areas together. If the caliper has pistons on both sides of the rotor, disregard one side.
Caliper Piston Area (in2) Master Cylinder Bore Diameter (in)
Up to 3.6 ⅝
3.6 to 4.2 7/10
4.2 to 4.5 ¾
4.5 to 4.7 13/16
4.7 to 5.5 ⅞
5.5 to 5.9 15/16
5.9 to 6.3 1
6.3 to 7.6 max 1⅛


I can't remember where I got this from (Wilwood, Tilton, CNC?) but hope it helps. I am looking to do something similar on my 68 Camaro but there is a real packaging obsticle to overcome with the Wilwood pedals on my project. If anyone has pulled this off on a 1rst gen please share the details.

[Crossupbill]

According to another post on here the C5/C6's use 2 40.5mm pistons so this would put you in the 3.6-4.2 category. That is if my caluclations are correct. .700" diameter seems small to me but whatever.

[jerome]

thanks for the help guys. my calculations ended up with 13/16 or 7/8 for the front master...went with 7/8 because wilwood carries it.

went with 1" for the rear explorer brakes (this was Wilwood's recommendation)

and 3/4 for the clutch (stock LS1 hydraulic throwout for T56)

used Earl's speedflex SS 10mm banjo to -3AN hoses
using 37 degree flares for 3/16 hard line and AN tube sleeves and nuts
bought clutch line from speedway with quick disconnect and -3AN fitting

[35spline]

As I mentioned I have been going through this exercise as well. I was most impressed with Tilton Engineering's Tech Dept. They ask you about a dozen questions (rotor size, pedal ratio, caliper size, tire diameter, weight of the car and distribution etc) to calculate the proper MC bore size. The answer was not what I expected but I will go with their recommendation.

[Payton King]

use as 7/8 master for the clutch you may be a little small.

I am running smaller masters on my twin set up but my pedal ratio is not as good as yours.

Once you get it up and running and if you feel there is still too much pedal effort to get yours to stop. Move the front 7/8s to the rear and get a 3/4 for the front. Pedal effort is a personal choice and most like a little easier pedal to push.