I'm trying to get more brake and stopping out of my 87...since the rebuild, its been a little weak on stopping. Even before the rebuild, I remember it never stopping on a dime, or being able to really lock the brakes up on the car.....
So... after I installed the rear end with disk brakes, I knew I needed an adjustable prop valve.... I installed it this week, and I now have rear braking, but its the same quality as I had before, not really great in the stopping dept.. I bled the out of the lines, and now I'm wondering if maybe I need to re-bleed the master cylinder, or perhaps maybe the MC was going before I did the rebuild.
maybe I should just upgrade the MC, and plan for larger calipers down the road?
any ideas , tests, or thoughts on this situation would be great
also keep in mind that I also added some extra weight to the car, and the tires are larger then stock on turbine rims
How does the pedal feel right now?
Is it spongy and soft or hard with little travel
depends..... backing out of the garage going slow, it feels hard and stops quick.... driving, the pedal feels about average, (not supper hard, and not super spongy). it's def not stopping the car quick enough for it to be safe though. I tested the back brakes with the rear end in the air... the brakes stop the wheels during idle, unlike before the adjustable prop valve.. they also dont seem to hold them tight enough. a small touch of gas and they will spin.....
it def feels all 4 wheel related, and not a front to back adjustment.
i just had a thought that maybe the MC ran dry while I was working on the car, but I never removed it, and I have pics of it still full of fluid while working on the car
Do you still have stock brakes up front or did you upgrade to 11" Mustang/Turbo Coupe rotors and calipers? My Thunderbird still has the stock brakes up front and 10" drums in the back. It will lock the tires in a panic stop.
I still have stock brakes up front .. Calipers, and pads are also new with the rebuild, along with all the brake lines. Calipers in the rear were still working when I got the 8.8 rear.. They also have new pads , and lines
can I do a pressure test on the MC?
Dude you built a tank! At least put stang brakes up front. You will improve it some. I put the adjustable prop on mine and ending up opening up almost all the way to get it to what I liked.
You put a lot of steel and weight in that car.
How much weight in weld was added.lol
Get a set of 11 inch spindles, followed by this.....
http://ssbrakes.com/i-10092994-disc-brake-kit-front-1-single-piston-with-11in-rotor.html
I have that very kit on my front end minus the master cylinder. It uses the 73 mm calipers as opposed to the fox Mustang's 60's. I have 10 inch drums out back. Personally I'd use a master that has a reservoir and low fluid switch. You could always call SSBC and see what they would sell the kit without the master for....
That's some crazy shiznit.
I was into my 2nd roll of wire........ 5 pounders plus all that frame steel. Think that was an extra 70lbs right there...lol
Paul, as much as I would love to do that...right now isnt the time....the vert is the project for now...EFI, and paint by winter..
I have another MC out of the parts bird...I think I should try that next if I cant remedy the brakes...
Kitz, I also had to crank the adjustable prop all the way to get rear brakes too
It sounds like your current master cylinder is a bit wore out
If you plan to swap it out I would also consider swapping in a 93 cobra brake booster, it will give you that extra braking power you need
Agreed.
You can pick one up for about $100 from most places. You will need a 2 port to 3 port line addapter setup. I know you're quite resourceful and could most likely make your own if needed. MM sells a setup as well. http://www.maximummotorsports.com/Master-Cylinder-Installation-Kit-1993-Cobra1994-95-GT-mc-in-1987-93-Mustang-P673.aspx
Cardone apparently carries a remanufactured version, however you would need to supply the reservoir. The reservoir carries a different part #, but I
THINK you can use one from a standard fox Cougar/T-bird/Stang.
http://shop.advanceautoparts.com/p/cardone-master-cylinder-remanufactured-10-3706/20351773-P#fragment-2
Dorman makes one as well. I believe it's new. It DOES come with the MC. Part # M390125
Best price I can find is Summit. http://www.summitracing.com/parts/dhb-m390125
$60 isn't bad at all.
You don't have to run the adapter if you use a MC from a 85 Lincoln Towncar. SAE threads, 1" bore, and it bolts up. Granted its the older style of MC but you avoid making lines or buying a kit.
When you added the adjustable proportioning valve did you gut the proportioning valve side of the combination valve (brass block on the drivers side all the brake lines go into) or did you just eliminate it? You have to gut the proportioning valve side of it if you use the adjustable proportioning valve for the rear brakes.
Darren
I removed the the stock block... I gutted it before, but I still wasnt getting rear brakes, so I just decided to get rid of it al together... I wouldnt mind an older style MC...
First I think I'm going to try the other one I have. If I still have a problem, I'll have to try another MC
Just to clarify you have the 10" brakes up front, basically TC brakes in the rear, stock MC and stock booster with the factory combination valve removed and a manual proportioning valve installed, correct?
Darren
for what its worth,,
all wheels **except** the front driver go through the stock proportioning valve which to this day still I don't understand.
even If you added a couple hundred pounds of steel, the brake system should be sufficient or safe feeling yet everyone here seems to have the same problems with stopping,, atleast all still running stock ,, which leads me to believe a brake booster might fix some of our issues.
ive never had to change a brake booster but also , I don't understand really what it does other than its very name which "boosts" the brakes,, maybe that's bad ?
I would start over again and bleed at each wheel,,, I use to think that you could stop when you heard no more air ,, that aint the case actually.. after the air is out a half dozen more bleeds on each zirk fitting especially for a system that's been disconnected for a while. My son and I will have to deal with this as well.
IMO, until the anemic Fox brakes off a Fox car have been swapped over to the base SN95 brakes (I'm not even bringing up the Cobra/Mach 1 brakes) a person thinks that the Fox brakes are sufficient. When the swap is made over to the SN95 brakes it is very apparent that the Fox brakes were at best but when that is all that is offered and a person does not know better it becomes adequate. The Fox brakes were never meant for these cars with 100, 200, 300 more hp than the factory put in them but yet we will go and spend countless hours and $$$ on the hp, wheels, stereo, etc. but more often than not the brakes remain the same which makes no sense to me.
Brakeology 101:
http://www.winbrake.com/training_autofundamentalsbrakes.html
Darren
correct.... I just ordered a cobra MC. it may be time to do some upgrading anyway..
If the booster and master were still available for the TEVES system in the Mark VII for cheap I'd swap a Mark VII brake setup into the Cougar yesterday.... The brakes on my Mark inspire MUCH more confidence then any other factory fox body setup.
To make your system work you and if you want to stay four lug then move up to the 11" front rotors and use the stock style 60mm calipers from the likes of an 87-93 5.0 Fox Mustang. From there install the 93 Cobra MC and 93 Cobra booster. This will match up well with your rear TC brakes and give you the exact same brakes that the 93 Cobra came with so your brakes should be really good. I would also suggest installing a manual proportioning valve and gutting the proportioning valve section of the stock combination valve if you still have that installed so you can fine tune the brake bias. If you still feel that the brakes are not quite up to snuff then work your way up to some better brake pads like the Hawk HPS. The fronts would be the HB263F.650 and the rears should be the HB580F.627 but I would call Hawk and verify. I run them on both my cars and love the feel and low brake dust for the added stopping power.
I am not trying to sway you one way or the other. I have had just about every imaginable stock Ford brake configuration between my two cars and I am going off of experience. If I had to do it all over again I would have just moved up to the SN95 GT parts and been done with it. When I had the stock SN95 GT brakes on my Coupe with the '99 PBR calipers and the Hawk HPS pads that thing would put you through the windshield if you did not have your seat belt on. I stepped up to the Cobra setup due to brake fade when having a little too much fun on the twisties.
Darren
Darren, what car would the 4 lug 11" rotors, and calipers be off of?
Sorry about that, I have added that info into my previous post. Basically the '93 Cobra used existing brake parts from the 87-93 5.0 Fox Mustangs and the 87-88 TC. The front brakes were the 87-93 5.0 Fox Mustang 11" rotors and 60mm single piston calipers. The rear brakes were off the 87-88 TC which are 10" calipers and I believe are 45mm single piston calipers. The brake booster and the MC were the only thing that was specific to the Cobra in that it did not come from the Fox Mustangs, Birds, or Cougars.
You could also opt to add the 73mm single piston calipers to this system which the 93 Cobra MC will support. If you decide to go this route make sure you order the 73mm calipers that have the steel piston and not the ceramic one. Maximum Motorsports also sells stainless steel caliper sleeves but I'm not sure how much a street car would need these or the calipers with a steel piston. I put all of it on my Coupe and again I am really hard on brakes so that was why.
http://www.maximummotorsports.com/Stainless-Steel-Brake-Caliper-Sleeves-1987-93-P666.aspx
I will tell you that I had the SVO calipers, MM SS sleeves, Performance Friction pads, and 11" rotors up front on my Coupe with stock drums in the rear and it stopped okay. This was all with the Mark VII rotors and Ranger axles for the cheapo five lug conversion running 97 Cobra wheels. I swapped over to the brakes off of a 1995 Mustang GT but I swapped over to the 99+ PBR calipers and it was like the car never had brakes before. The reason for using the 99+ PBR calipers is that they are dual piston calipers and have a higher clamping force than the 94-98 single piston units.
Darren
the spindles will have to be changed too?
nevermind, I was just at coolcats... guess its time to start collecting parts
You got it man. IMO the 93 Cobra setup was what should have been the stock 5.0 brakes and the 5.0 brakes should have been the stock four cylinder stuff. Good luck with it, I think you will be more than happy.
Darren
thanks for the help and info
I installed the Cobra MC today...... The car stops really well now. Still have to do some final front-rear adjusting, but its 1000% better then it was. Guess I'll save up for the larger brake upgrade for my next mod.
Glad you got that figured out. Nothing worse than mushy brakes.
Darren
I couldn't believe how big of a difference a new wheel cylinder, new pads and master cylinder changed my 86. Brake pedal still feels a bit vague at times, but i can lock up the tires and the car won't pull either direction.
i'm going to bleed the lines again, just to be sure I got all the air out
I bought one of those motive power bleeders, works great and it was well worth the $50-$60.. there's instructions on-line to make one too if your looking to save $$ or just feel like making your own.
I never understood why you forced air bubbles from the highest point of the braking system to the lowest point instead of the other way around.
I think I'm gonna try the old school hold the pedal down method this time...I already gravity bled, and suction bled them before the MC change...
whats really strange...is that then I got the old MC off and did a bench bleed to see if it had trapped air in it, I couldnt even push the piston in
Nice it sounds like it really needed the master cylinder
I've always used the old school method with someone working the pedal while I work the bleeding screw and it's always worked great
I've thought about using those bleeders with the check valve though, they seem pretty nifty
So on this topic, I understand that my setup is just a little different but the problem is relatively the same so I'm interested to see what you guys have for suggestions. I have a 5 lug conversion. 95 mustang gt spindles up front with 97 gt axles in the back. I have the 97 gt rotors and calipers all the way around. I ran new brake lines the whole way up to the proportioning valve, which is also from the 97 gt. Now, I am running the factory 88 cougar Mc and booster. My pedal goes halfway to the floor before it starts applying. It will stop, but I need ample room. Obviously my Mc isn't cut out for the job. So which do I go with? A 97 mc? Even though my car isn't abs? Or should I go with a 95 gt mc? Or a cobra mc? And should I upgrade the booster as well? Any help is appreciated. Thank you
Well if you went with a 97 GT master cylinder it would be a nice combo, problem is the 97 GT used a hydro boost setup so it would complicate things somewhat
A 95 GT master cylinder and a 93 cobra brake booster would result in basically a full brake setup from a 95 GT on your car, the 93 cobra brake booster would also be a bolt on to the master cylinder and your car
I believe the 95 GT master is 15/16" bore while the 93 cobra master is a 1" bore so the 93 cobra Mc will yield a firmer pedal with less fluid force, Vise versa with the 95 GT.
I would opt for a manual proportioning valve for the rear bias rather than stick with the one designed for a 97 GT Mustang
Also note that you'll need a 3-2 line kit for the MC and to fit the larger brake boosters you might need to either slot the holes on the firewall or bash in the shock tower to make it fit
Okay great. So why would I need a 3-2 conversion kit? Couldn't I just throw the adjustable valve in the rear line and gut the original pv?
I think you might be able to actually
The way I setup my manual PV I just eliminated the stock one
IIRC I did that because my 3-2 kit came with the master cylinder I bought
Well, could I opt to stay with the 88 xr7 brake booster and just run a 93 cobra mc and adjustable pv, and just have a stiffer pedal?
Okay, I will explain this again. You now have SN95 brakes on the car which are the size that the V8/V6 cars run and you are running a booster and MC that were for the anemic Fox brakes...they do not mix well. This is due to you changing the braking bias on the car as well as the needed fluid volume displacement by the MC and the overall force to work the brake pedal. You can come this far so why not just get the 93 Cobra MC and 93 Cobra booster and make it work right? This will also set you up for the Cobra brakes if you so choose later on down the road.
Gut the proportioning valve side of the combination valve and get the block off nut for the combination valve from Late Model Restoration Supply. Install a manual proportioning valve on the rear brake line to dial in your brake bias.
Darren
I installed the Cobra MC on my 87, and replaced the factory prop valve, with an adjustable prop valve.... like night and day stopping now... I will do the same on the vert, plus add the booster...it stops ok right now, but theres always room for improvement seeing it has a 5 lug swap on it too
I never do it any other way.
to bleed I use a machete
pump up the brake, while holding pressure..........then......
put the blade down on the pedal
tilt the steering wheel all the way down
now bend the machete till the handle is under the lowest part of the steering wheel and walk away.
loosen bleeder and the machete pushes brake pedal down and holds it there... acts like another person.
wash rinse and repeat
protect pedal with something under the blade
i do the same thing but have a small crowbar that will fit between the pedal and the seat
I just got that $30 pneumatic bleeder from harbor freight. Woot woot
Machete? I use a big wooden dowel. Less chance of me cutting something in the car ;)
lol... I was wondering who else caught the machete comment