Let's talk about brake systems

Let's talk about brake systems for 3800lb race cars, 2500lb race cars, etc. 12 sec, 11 sec, 10 sec and then some. Disc brakes up front everyone wants, but not everyone has gone there, what is the best master cylinder to use? Mine is a manual replacement, that is leaking, so needs to be replaced! I know alot of you use the '80s truck master cylinder, do you buy a new one at the parts store, is it a reliable way to get one. I'm not sure we know the exact reason for Bobb's accident, but if it was a brake issue, we need to discuss it here, just as we have the other safety related stuff. So let's hear your thoughts. Thanks Roberta

 

roberta,

i'm glad you brought it up. this is one of biggest pet peeves. BRAKES or lack of.

everybody builds cars to GO, but they really don't the extra mile for WHOA part.

whether its restored or racing, you need the best brakes for you, the other person and your car. it certainly is not worth lawyer time.

there are plenty of places we can find out which product will do the best job for our needs. time for everybody to start looking and report back to all.

our car has 4 wheel disc, but the master is going to get thrown out for a new one. am going to see if i can have an e-brake setup for it. also going to look into a master kill switch that does the motor and fuel pump at the same time. maybe there is a mercury switch available or something similar to use in a rollover where it shuts everything down. certainly would be easier if the car had a computer and you could build right in to it.

john

 

Good topic Roberta,

After now being able to drive my Skylark, it can be an event to slow it down with the manual drum brakes while testing WOT shift points!

 

You mean my 4 wheel alunimum drums arent enough?????

 

You have aluminum!?

Man, how do you rate? ou:

 

I've got Wilwood discs all around. Since my firewall is aluminum and won't support the master, mine is mounted thru the floor about 8 or 10 inches in front of my seat. It's a mid-90s Camaro master cylinder. If the brakes were to fail, I'd pull the chute. I tried it out a few times last season and it slowed the car down quite nicely. It's a little bit of a pain to pack up, so I don't use it on a regular basis. No real need for it. I'll just use it often enough to keep it limber.

 

Here's a thread of a test I did just two weeks ago. I put new ceramic pads on my car. Now I had rebuilt my entire brake system two years ago. But I was looking to improve the car's braking ability. I do believe I was successful. Just bare in mind that our Buicks are HEAVY cars. You'd probably need some big disc brake all around to really slow it down quickly.

http://www.v8buick.com/showthread.php?t=56693

Here is also a thread on putting rear disc brakes on our cars for cheap $$$.

http://www.v8buick.com/showthread.php?t=54348&highlight=rear+disc+conversion

Just another note to most here, our old rear drum brakes need to have the emergency brake used once in a while to help adjust the shoes back there. I found this out after doing all this research on braking systems. Just apply the emergency brake, not real hard, and then release it. That will adjust the bottom of the shoes out so that they are close to the drums and activate quickly when you apply the brakes. Don't mash it down too hard or you could actually adjust them too far and the shoes will drag on the drums for a while. Just thought I'd pass that along.

 

i had 4 wheel alum. drums on the race car until i upgraded to wilwood front discs last year. at 125 with the drums the brakes would fade, now with the wilwoods they dont fade and i can stop in half the distance.

i think i may have talked dad into putting front discs on "Scat" and Randy putting discs on "Outrageous". :TU:

after Bobb's mishap, i am also thinking of installing a hand e-brake. Dad also lost the brakes on "Thumper" years ago and put the car into a cornfield. ou:

 

Brakes, I had the stock setup for years on my 71, front disc,rear drum.
last year i went with Willwood disc brakes all around, and have been happy with the stopping power, it is the setup for the heay car, as mine weighs 3880 with me in the car, master cylinder is manual and from master power brakes as Willwood told me to buy.

Bruce

 

for street use converted from 4 wheel drum non power to, front factory disc and rear drum power assist. Night and day diffrence between the two. I also drive my car every day (less white stuff) and I just did factory conversion. yes you still get brake fade when you have fun and get out on an open widing road but they come back rather quickly.

Nate

 

Dot 5 Brake Fluid

Years ago when I first got my GS running after the body off restoration I installed new everything in the brake system and went with Dot 5 silicone fluid since it doesn't eat paint when spilled on it. As it turns out that is true but it also doesn't absorb the moisture that collects in the system over the years. Once the brake system is used hard (ie. several passes at the drag strip with hard braking), the moisture works it's way to the wheel ends, then you lose your pedal. Moral of the story is to either bleed your brakes every season or just don't use Dot 5. Fresh fluid every year is always a good idea. I had changed the master cylinder once but when I lost my pedal the second it started me thinking. Simple bleeding of the rear solved the issue.

Hope that helps.

 

Anybody ducting air to cool their brakes?
I used to drive an MGB, and it made a real difference on it. Oughta be much easier on a big ol' Buick...

 

Obvious but true

Lines should be inspected carefully.

Main failure points are corroded hard lines or blown soft lines. New lines are very cheap insurance compared to the potential disasters that can happen.

Be especially careful after having a car towed. I had some manic mechanic break the hard line on the third member when he hooked onto the rear axle to tow my car home.

 

I have factory front disc, w-std pads, and rear drums. Using a GM Truck aluminum master, after 4 years of stoping my 3500lb race car i am getting brake fluid inside the the car..replacing it this winter..i have always been able to stop the car effortlessly. My concern is the connection of the brake rod and the master cylinder, those of you who use the brake light switch mount with a bolt and nut in it to stop the neg travel of the brake arm could be in for a BIG surprise.

Personally even the BEST brakes can fail under extreme circumstances, im thinking a backup plan is the only way to be safe......chute...e-brake,,,,anchor and chain........what ever.


You could throw a balancer weight and take out a brake line, or throw a rotating engine part into the brake line or regulator....thats why they call them "freak" accidents.

Plan B!!!!!!! Second set of braking devise!!!!

My 2 cents.........food for thought......have a safe day!

 

I use a stock front disk brake setup with drilled "Power Master" rotors (from Summit cheaper than stock) and metalic pads.

Strange disk brake setup in the rear.

The master cylinder is a stock manual disk brake setup (came OEM on Olds Cutlass 70-72). Filled with Castrol Dot 4 fluid.

The big improvement came from the Russell stainless brake hoses that replaced the factory rubber hoses.

All hard and moving parts were replaced with the exception of the spindles, backing plates and caliper mounts.

This system will lock up my brakes at 140mph if I want it to and has little or no brake fade.

Mike
carcrazy455@yahoo.com

 

Dot 5 ..... Nooooo

Rob,

Be very carefull running the DOT 5 brake fluids. Eventhough this brake fluid can handle the heat better than DOT 3 or DOT 4 it still has a serious drawback. It EATS some of the seals throughout your braking system. When I had the old car I talk with wilwood. They said dont run DOT because it will eat the seals in the brake cylinder. We just finished up our new car that has Lamb brakes all the way around the car. So... I called Lamb. There response was "NEVER run DOT 5 brake fluid. It will eat the seals in our brake components." So that is two for two.

Be Carefull

 

You can also get a dual master cylinder that makes the front and rear brakes totally separate. That way even if you do lose a brake line, you will still have half of your braking system.

 

Great stuff!

And I have heard the same about DOT 5, was going to put in the '73 Vette, because the 4 piston disc brakes were very prone to corrosion, but never did it cause of the seal issue. I have aluminum drums on the front, and still steel on the back, was about to put aluminums on the back but the ones I found wouldn't fit, so MG, what are you using for aluminum drums on the back. I think Bobb had Wildwood discs all around, but I don't know what he was using for a master cylinder or where it was mounted. I see where Doug has his, and I know Scott McConnell(aka Big Bad Buick, '65 GS, that ran 9s back in the day) had his in the same place as Doug. And so do many other fast cars!

 

Berta -

I have aluminum rear drums from an eighties G body on my car. Monte Carlo, I think. They bolted right up and used the stock shoes and linings.