Need some help/advise on my Manual brake setup

[64LS1Nova]

Hi Guys, My brakes are driving me nuts! They seem to be the only part of my car that is not working up to snuff. Here is my setup. I have a Chevy II with Mustang II front suspension. The front brakes are 11" SSBC with 4 piston calipers (1 3/4" pistons), Rears are factory 95 Camaro disc brakes with the pbr calipers (the ones with built in e-brake). I am running a Wilwood pedal assembly with dual master cyl. under the dash. .7 bore for front and .75 for the rear. Pedal is 6.25:1 ratio


I am in the process of upgrading my front brakes. I'm looking at different 13" setups and trying to figure which one is best for me. I'm looking at the Wilwood 140-9801, the SSBC 13" 3 piston, and the Kore3 with Corvette calipers. I'm also considering buying hubs, adding 13" rotors and making my own bracket for my existing 4 piston calipers.


Seems like no matter how I adjust the bias bar I just can't get this thing to stop well. Is there anything you guys can see with my setup that is off? Should I be running a 5/8" bore on the fronts?

Thanks for any input,
Frank

[a67]

Likely need better pads.... Front caliper bore area is 4.8", which is more then enough.

Bob

[Payton King]

Hey Frank, Have you spoken to Ron about this? Pads will make the biggest difference as stated above, but not sure what pad shape you are running or the compounds available.

Are you going to try and autocross/road race that beast?

[64LS1Nova]

Thanks Bob. These Hawk 9012 pads did make an improvement, but I can't live with the amount of dust driving around on the street.

Payton, I have talked with Ron about it. We are at the point where we think a pressure reading is in order. The front pad shape is the rectangular style like the old wilwoods. It's the kind that has 2 pins that you pull, then the pads slide out without removing the caliper. Not allot of surface area on these, which is another reason I would like to upgrade.

I have every intention of doing a race with you guys this year. I need to see if I like it as much as I do drag racing. I hope I don't get bit with the bug as bad as Ron has! haha

[Classic Nova & Performance]

Frank,

I think you are on the right track on doing a pressure check. That will give you some numbers & an idea of what is going on.

Re: Autocross vs Drag Racing: I had a blown 67 Nova & am building another full tube chassis 66 Nova to replace it. After riding w/DSE at Columbus I shelved the drag car until a later date so I could put together a pro-touring car. It is a kick in the a##!!

[64LS1Nova]

Thanks Walt. I'm going to attempt to do both with the same car. I should be able to de-tune it down to 750hp or so, which takes allot of the white knuckle experience out of it. lol These brakes have really been keeping me away for now. I hope to have them figured out this winter!

[chevyshack]

Why not get a booster and make it power brakes?

[64LS1Nova]

The resivoir is the only thing on my firewall. I have a dual Master cyl. setup hidden under the dash. Not much room under there for a booste since I have the vintage air heater and wiper motor under there also.

https://static1.pt-content.com/images/noimg.gif

[Payton King]

From what I have found out, you will need a fairly aggressive pad when you are running manual brakes to get them to stop. Then you have a fair amount of dusting. I really liked the AX6 (bobcat) pads from Carbotech. They are an autocross pad that I ran on the street with my yellow car. They are dusty, but have great cold bite and made a huge difference. Only other thing would be have power brakes so you can run more of a street pad with less dust but still get the braking you need. Would still need to change pads if you got on a road course.

Look here, not cheap but works great. http://www.abspowerbrake.com/ehpm.html

[64LS1Nova]

Thanks Payton. What is you opinion of going to a 5/8" bore for the front brakes.

[Payton King]

It makes for a longer pedal but does generate more pressure. What style master are you running? I have that size in a tilton that I could send you to try. I sent Ron my caliper brake pressure gauges. Tell him to bring them over and see what kind of pressure you are making before you change anything.

I also noticed I said the AX6 were the bobcat pads. I was wrong. That is their street pad I ran on my wife's M3.

[64LS1Nova]

Thanks a ton Payton! I am running the Tilton 75 series masters. We are going to do the pressure check tomorrow night. I will post up the results afterwards.

[Payton King]

That is the same series I have. Let me know if you need it or any other sizes...took me a while to land on the correct ones and I have one of every size except .70 and 3/4.

[64LS1Nova]

Payton. How do I know what pressures to look for when I check it? Your kit has 2 guages, I'm assuming you put one in the front and one in the back and press on the brake pedal with a good bit of effort. Is that right?

Thanks,
Frank

[Payton King]

Take the bleader out and screw those in. You are looking for about 1000 to 1200 psi in the front and 850 to 900 in the rear assuming your calipers are sized correctly for your application. SHould take about 100 or 120 lbs of leg pressure to generate those numbers.

[64LS1Nova]

Well, I gave it a shot Payton. The front brakes have a different size bleeder than your guages. The thread size on the bleeder is bigger than the thread size of the guage. No big deal though. I ordered a set of Wilwood 13" 6 piston superlites today. I will put them on, then check the pressure. I did also find that I have the 3/4" MS on the fronts and the 7/10" on the rear. So it looks like I'm backwards. I will swap them and install the new Wilwoods and hope for the best.
Do you think it's even worth me swaping since I have a bias bar setup? Or would I be wasting my time?