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Discussion Starter #1
I finally finished with my Granada front disc brake conversion. I am really disappointed in the stopping power I have vs the drum brakes. It seems as if the discs are not as good as my drums were. I have to really put the pressure on the pedal to stop quickly. I used the Maverick master cylinder and the calipers, rotors and all else was new except the metering/proportional valve. What could be the problem? I have heard that the pads will seat and get better is this correct. I had a leak at the line connector on the M/C for the front brakes and when I first took the car out the brake pedal would ease down. I tightened this up and stopped the leak. Maybe I should bleed the front again, would air get back in system with the small leak I had? Anyone else have trouble with their Granada brakes not working as good as drums? I have no power assist just manual discs.
 

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I have Versailles (Granada) on the front of SWMBO`s vert. They seem to work fine to me. maybe even as good as the brakes on my `91 Foxbody ;) Although I do have a power booster
Do you have the correct prop valve?
 

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Steve, if fluid gets out, air can get in. Definitely re-bleed. I love my granada setup, are you sure you have the lines plumbed correctly on the proportioning valve? All the bleeders are seated good and snug after opening? If you need any help give me a call, I can drop by this weekend...gary. If all else fails, I'll gladly swap my pos 66 for your gorgeous Mach! ::
 

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I also have an extra proportioning valve if you need to try it, in case that is the problem... :p Brake problems do suck! ::
 

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Are you saying it doesn't stop as well or that it takes more pedal force to produce the stopping power? I have manual Granada discs also (on a lighter '65 though). Pedal effort is substantial, but it stops well. What procedure did you use to bed the pads? What pads are you using? As another poster mentioned, if you leaked fluid you may have pulled air into the lines. Please provide more information about your problem.
 

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This will be an interesting post to follow for I was just about to go out and start looking for Granada parts. Hmmmmm.........
 

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Discussion Starter #8
It just seems as if I don't have a full pedal and it takes a lot more pressure to stop, but I only drove it about 2 miles What is the procedure for bedding the pads? I think it's air in the lines.
Gary:I plumbed the lines per the Ford service manual.

Thanks
 

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Hmm...
Something does not sound right. I converted a drum setup to disc using vintage Mustang parts and the Maverick master cylinder. I am quite pleased with the results in terms of stopping power and pedal effort. I realize that it is not the exact setup you have, but the brake differences (as opposed to the spindle/geometry/tie rod end differences) should be minimal.

I am suspicious of air being in your front system, although not from the minor distribution block leak you had. It would help to know if you also worked on the rear brakes or simply converted the fronts.

Try to get someone to watch you as you lock up the wheels from about 20 MPH to see if you are locking up the fronts or just the rears...

Also with Mustang calipers it is possible to install the calipers on the wrong side and end up with the bleeders facing the wrong way (up instead of back) which will not allow a full bleed. I don't know if this applies to Granada calipers or not.

You did bench bleed the MC before bleeding the lines, didn't you?

I encourage you not to despair about having converted to disc brakes and having worse performance; there is almost certainly a problem to be fixed prior to your final judgement.
Good luck!
 

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Discussion Starter #10
No I did not bench bleed the master cylinder. I should have but I have installed many in my time with and without doing it.
 

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I was just going to post whether or not you had bench bled! 2ndGen beat me to it :eek: Remove and bench bleed and your problems will go away. I have been thru this before, myself. You are not going to get as much action pushing the pedal as you will with the mc sitting in the vise (gently) where you can really stroke that puppy. Then all the air will be expelled! I know this is just what you want to hear...to have to twist into several pretzels and bust some more knuckles to get it back off and then on, but you have to do what you have to do... ::
 

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One other thing Steve. I once got an mc for my blazer, from autozone, and that puppy never did work great. I finally took it off after about a year and returned it for another. The new one worked great. I think it was just too worn for the rebuild and leaked fluid by the piston on the inside. If the one you have is a rebuild unit, it could be a bad one...just fyi...
 

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As a first order approximation, do not remove your master cylinder. Go to Autozone/Kragan/Pep Boys/NAPA and buy the Raybestos MC bleeder kit for $1.59. It consists of two short pieces of tubing, plastic fittings, and a clip to hold the tubes in place. Disconnect the main feeds to the distribution block, insert the plastic fittings into the MC, and loop the tubes up into the reservoir. Use the clip to hold the ends of the tubes UNDER the fluid in the reservoir. Now pump the pedal with long strokes until no more bubbles appear... not quite as good as a bench bleed because you can not usually get full strokes , but this works fine MOST of the time and keeps you out from under the dash.

If you feel you are not getting reasonable stroke length, you can disconnect the brake pedal and do the full equivalent of a bench bleed with the MC still mounted in the car.

I agree that brake parts are not the area to economize; buy the best components you can afford.

Good luck!
 

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That would certainly be worth a try. Also, his mc probably came with the kit for bench bleeding as you described.
 

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I totally disagree with the need to bench bleed the MC. If it's working at all, then bench bleeding will yield very little or no results. BLEEDING still needs to be done, but it's related to the front system not the MC.

Also, there SHOULD be increased pedal effort if you swapped from drum to disc brakes (and didn't add a power booster). There arne't too many all drum cars with power boosters (compared to disc brake cars) because drum brakes take less effort than do disc.

On a side note: I had Granada brakes on my car and after spending $500 and $700 at two different brakes shops, I gave up trying to make them work. I can't tell you how many times I tried on my own as well. The car either pulled, took TOO much effort for little results, or just didn't have the stopping power. I hope your set up finds different results but I'd start with bleeding the front lines and expecting extra effort. (also: if you're pads are brand new, it takes about 100 miles of regular driving to wear them in. A little longer the more metallic they have in the pad)
 

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Disc brakes dissapate heat better and therefore resist fade much better than drums; but they are not self energizing, so they require more effort to get to the same level of stopping.

A benefit of that characteristic is that since it is so much harder to get them to full lock the driver has much more modulation control with disc brakes.

Another related benefit is that the pressure applied to each disc on the front will be even because it is hydraulic pressure all the way to the piston. Drum brakes can grab and pull to one side since the hydraulic pressure is transfered through a mechanical pivot point before getting to the pads. If the drum brakes are not adjusted to match very near perfectly then the mechanical pivot will apply uneven pressure when comparing the amount applied to the right versus the left.

IMNSHO it is also why power brakes became the default standard after front discs became the default standard on most cars.

John Harvey
 

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Agreed, and also and probably most imporantly to the consumer, easy of replacing parts. Changing a rotor and set of pads requires almost no mechanical experience, while taking the drums off and replacing spring loaded shoes, the springs, etc. can be daunting.
 

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So does it sound to me that if you go disc, you should go power disc brakes? I'm working on my daughter's first car ('65 couple) and was planning to do disc on the front, but if it takes more strength to stop.........
 

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In reference to the original Kelsey-Hayes 4 piston '65 front disc brakes, I haven't noticed a real big increase in pedal effort over the stock drum brakes. I used to drive my dad's 4 wheel drum '65 Mustang and don't have a problem adapting to my '65 GT with a T's brakes afterwards. Going from Friggin' Futura's power discs (when she used to run) to the GT's was night and day! I like the feel of the GT's brakes better.

Just some more info bits.

Dean T
 
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