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Disc o tech - blues....my 4 wheel drums were better. #1692649 10/30/14 10:49 PM 10/30/14 10:49 PM
Joined: Aug 2003 Posts: 643 Toronto, Ontario, Canada plazomat OP mopar
plazomat OP mopar Joined: Aug 2003 Posts: 643 Toronto, Ontario, Canada	Just finished off a disc conversion using.. 10.9 inch rotors - new 72 ebody pin calipers - new 72 ebody spindles (w/bearing adaper) - new 1 1/32 master - new all new lines and hoses 10 * 1/3/4 drums out back, not new but in great shape. no combination or proportioning valve. Brakes just suck - low but hard pedal and I gotta stand on it to stop the car.. Brakes are bled I guess - no spongy but low and hard as hell pedal. I know a combination valve is in order but will that fix the feel of the brakes? - which year/body valve should i get? Will a generic under master cyl gm unit work? I guess I need a residual pressure valve in the rear lines as well - will that fix the pedal height? What steps should I take to resolve this - I don't want to just throw a bunch more variables into this system and never get it right.. Thanks Plaz

Re: Disc o tech - blues....my 4 wheel drums were better. [Re: plazomat] #1692650 10/30/14 10:55 PM 10/30/14 10:55 PM
Joined: Dec 2007 Posts: 18,157 Mass DAYCLONA I Live Here
DAYCLONA I Live Here Joined: Dec 2007 Posts: 18,157 Mass	No mention of what type of master your using?, drum/drum?, disc/drum?, OEM?, aftermarket? You'll need a proportioning valve...OEM or aftermarket, your choice Power assist?, non power? What pedal set up was used? Are the rear drums adjusted properly? (travel)

Re: Disc o tech - blues....my 4 wheel drums were better. [Re: plazomat] #1692651 10/30/14 11:05 PM 10/30/14 11:05 PM
Joined: Feb 2005 Posts: 28,312 Cincinnati, Ohio Challenger 1 Too Many Posts
Challenger 1 Too Many Posts Joined: Feb 2005 Posts: 28,312 Cincinnati, Ohio	Quote: Just finished off a disc conversion using.. 10.9 inch rotors - new 72 ebody pin calipers - new 72 ebody spindles (w/bearing adaper) - new 1 1/32 master - new all new lines and hoses 10 * 1/3/4 drums out back, not new but in great shape. no combination or proportioning valve. Brakes just suck - low but hard pedal and I gotta stand on it to stop the car.. Brakes are bled I guess - no spongy but low and hard as hell pedal. I know a combination valve is in order but will that fix the feel of the brakes? - which year/body valve should i get? Will a generic under master cyl gm unit work? I guess I need a residual pressure valve in the rear lines as well - will that fix the pedal height? What steps should I take to resolve this - I don't want to just throw a bunch more variables into this system and never get it right.. Thanks Plaz What makes you think they will work without either valve in there? How do you have the lines junction ed together now?

Re: Disc o tech - blues....my 4 wheel drums were better. [Re: DAYCLONA] #1692652 10/30/14 11:07 PM 10/30/14 11:07 PM
Joined: Aug 2003 Posts: 643 Toronto, Ontario, Canada plazomat OP mopar
plazomat OP mopar Joined: Aug 2003 Posts: 643 Toronto, Ontario, Canada	Thanks so much for the response..here's more info Disc/Drum 1 1/32 unit for an 85 dippy - new parts store purchase coni seal brand Manual - no power Manual pedal setup that was in car since new - 4 wheel drums Rear drums adjusted to slight drag Only a proporting valve or a combo valve (prop/metering functions) Just throw all parts at car or take in stages? Plaz

Re: Disc o tech - blues....my 4 wheel drums were better. [Re: Challenger 1] #1692653 10/30/14 11:17 PM 10/30/14 11:17 PM
Joined: Aug 2003 Posts: 643 Toronto, Ontario, Canada plazomat OP mopar
plazomat OP mopar Joined: Aug 2003 Posts: 643 Toronto, Ontario, Canada	Quote: What makes you think they will work without either valve in there? How do you have the lines junction ed together now? The stock drum/drum unit is in there - its just a distribution block and does not provide any valving or metering.. Plaz

Re: Disc o tech - blues....my 4 wheel drums were better. [Re: plazomat] #1692654 10/30/14 11:22 PM 10/30/14 11:22 PM
Joined: Sep 2007 Posts: 14,889 up yours Supercuda About to go away
Supercuda About to go away Joined: Sep 2007 Posts: 14,889 up yours	You really didn't follow the disc-o-tech instructions, now did you. The M/C is too larger of a diameter. They say there are no such thing as a stupid question. They say there is always the exception that proves the rule. Don't be the exception.

Re: Disc o tech - blues....my 4 wheel drums were better. [Re: plazomat] #1692655 10/30/14 11:24 PM 10/30/14 11:24 PM
Joined: Nov 2005 Posts: 15,118 85086 moparpollack Lil Herman
moparpollack Lil Herman Joined: Nov 2005 Posts: 15,118 85086	Pad material can affect stopping ability. My 64 Polara had the lifetime autozone pads that didn't stop for anything. 56 Plaza 63 D100 step side 67 Coronet, 68 Roadrunner, 69 Super Bees, 69 Coronet 500 convertible, 70 Roadrunner Post, 79 D150 360, and a severe case of Mopar a,d,d

Re: Disc o tech - blues....my 4 wheel drums were better. [Re: Supercuda] #1692656 10/30/14 11:30 PM 10/30/14 11:30 PM
Joined: Aug 2003 Posts: 643 Toronto, Ontario, Canada plazomat OP mopar
plazomat OP mopar Joined: Aug 2003 Posts: 643 Toronto, Ontario, Canada	Quote: You really didn't follow the disc-o-tech instructions, now did you. The M/C is too larger of a diameter. Doesn't he recomend a master from a 76-8 F body? and aren't they 1 1/32? What am I missing here?

Re: Disc o tech - blues....my 4 wheel drums were better. [Re: plazomat] #1692657 10/30/14 11:46 PM 10/30/14 11:46 PM
Joined: Dec 2007 Posts: 18,157 Mass DAYCLONA I Live Here
DAYCLONA I Live Here Joined: Dec 2007 Posts: 18,157 Mass	Quote: Thanks so much for the response..here's more info Disc/Drum 1 1/32 unit for an 85 dippy - new parts store purchase coni seal brand Manual - no power Manual pedal setup that was in car since new - 4 wheel drums Rear drums adjusted to slight drag Only a proporting valve or a combo valve (prop/metering functions) Just throw all parts at car or take in stages? Plaz Feedback,...if you repeatedly pump the pedal, does it gain noticeable height?, or maintain about the same height, does maintaining depressed pedal pressure cause the pedal to slowly sink?

Re: Disc o tech - blues....my 4 wheel drums were better. [Re: DAYCLONA] #1692658 10/31/14 01:11 AM 10/31/14 01:11 AM
Joined: Aug 2003 Posts: 643 Toronto, Ontario, Canada plazomat OP mopar
plazomat OP mopar Joined: Aug 2003 Posts: 643 Toronto, Ontario, Canada	Pumping does not change pedal feel at all. Holding pedal down hard with foot, no sinking what so ever.. Plaz

Re: Disc o tech - blues....my 4 wheel drums were better. [Re: plazomat] #1692659 10/31/14 01:39 AM 10/31/14 01:39 AM
Joined: Nov 2003 Posts: 36,040 Lincoln Nebraska R RapidRobert Circle Track
RapidRobert Circle Track R Joined: Nov 2003 Posts: 36,040 Lincoln Nebraska	Quote: no combination or proportioning valve. Brakes just suck - low but hard pedal and I gotta stand on it to stop the car.. I think the low pedal is key & others have had to stand on the pedal (at normal height tho) with the wrong bore MC. In my case: 65 dart with 74 A discs (76-2.75 calipers) with aftermarket (ceramic? pads) and a 1&1/8 dual alum MC with adapter plate & 10" (7&1/4) rear drums and OE drum splitter (mismatched system) and it would put me in the windshield if I stood on it. I would put it up on stands have a helper spin the fronts as you work the pedal and idle it in gear & see how the rears act. Holler with any news. I'm thinking inadequate psi (line restriction somewhaere) if there is no mechanical malfunction at the corners but there is something going on/wrong with the low pedal (find/fix that). I had that exact same symptoms (height was OK tho) on the stock car from a braided line bent at too severe of an angle. EDIT Is the MC adapter plate what is making the pedal too low and post what the pedal ratio is Last edited by RapidRobert; 10/31/14 01:49 AM. live every 24 hour block of time like it's your last day on earth

Re: Disc o tech - blues....my 4 wheel drums were better. [Re: RapidRobert] #1692660 10/31/14 02:30 AM 10/31/14 02:30 AM
Joined: Aug 2003 Posts: 643 Toronto, Ontario, Canada plazomat OP mopar
plazomat OP mopar Joined: Aug 2003 Posts: 643 Toronto, Ontario, Canada	Thanks for the input RR. I was wondering about the adapter plate as well. I think its an AR engineering one with a step where the master bolts to..http://arengineering.com/products/master-cylinder-adapter-four-studs/ I will double check the lines for kinks and what not and figure out how to measure the pedal ratio.. Plaz

Re: Disc o tech - blues....my 4 wheel drums were better. [Re: plazomat] #1692661 10/31/14 03:20 AM 10/31/14 03:20 AM
Joined: Feb 2010 Posts: 18,493 Granite Bay CA Kern Dog Striving for excellence
Kern Dog Striving for excellence Joined: Feb 2010 Posts: 18,493 Granite Bay CA	Maybe I missed something but I don't recall the car you are working on....In addition, there are a few mistakes I see here. NO Diplomat came with manual brakes. The master cylinder from a Diplomat is sized for power assist. Any disc/drum system needs an actual proportioning valve. The front calipers use a much greater volume of fluid as compared to the rear. The stock Mopar disc/drum proportioning valve held off pressure to the rear until the FRONT built up pressure. By using what is known as a "distribution block", (No metering, just a junction for the brake lines) your calipers are only getting the volume and pressure that the old front wheel cylinders received. NOT good and nowhere near enough. I have a bunch of actual disc/drum proportioning valves that would work. The ones from mid 70s A body cars are pretty easy to find and work well. PM me if you want a screaming deal on a used Prop valve.

Re: Disc o tech - blues....my 4 wheel drums were better. [Re: Kern Dog] #1692662 10/31/14 03:29 AM 10/31/14 03:29 AM
Joined: Feb 2010 Posts: 18,493 Granite Bay CA Kern Dog Striving for excellence
Kern Dog Striving for excellence Joined: Feb 2010 Posts: 18,493 Granite Bay CA	These are often called the "Texas" valve for obvious reasons. They are the ones I mentioned from a 73-76 A body. 8316762-June12243.JPG (203 downloads)

Re: Disc o tech - blues....my 4 wheel drums were better. [Re: Kern Dog] #1692663 10/31/14 03:53 AM 10/31/14 03:53 AM
Joined: Jan 2003 Posts: 1,043 Slidell, La. D doctor_mopar super stock
doctor_mopar super stock D Joined: Jan 2003 Posts: 1,043 Slidell, La.	I would say a smaller bore master cylinder is in order. Of course the proportioning valve also. Take not that a rebuild kit and instructions for the proportioning valve is available cheap from Muscle car research online. ------------------------ It doesn't matter what you do.........As long as you look good doing it !

Re: Disc o tech - blues....my 4 wheel drums were better. [Re: doctor_mopar] #1692664 10/31/14 11:52 AM 10/31/14 11:52 AM
Joined: Jan 2003 Posts: 21,067 Niles , Ohio T therocks oh wait.but hey.lets see.oh yeah.
therocks oh wait.but hey.lets see.oh yeah. T Joined: Jan 2003 Posts: 21,067 Niles , Ohio	I use nothing but 70C body masters.I run Ceramic pads with my pin types on the 65.Stops great and good pedal.The stock spliter will work if you use an adjustable PP valve to the rear.I use 5th Ave PP valves.Mine have been on at leats 15 years and no problems even at 120 it stops great.Rocky Chrysler Firepower

Re: Disc o tech - blues....my 4 wheel drums were better. [Re: plazomat] #1692665 10/31/14 02:15 PM 10/31/14 02:15 PM
Joined: Dec 2007 Posts: 18,157 Mass DAYCLONA I Live Here
DAYCLONA I Live Here Joined: Dec 2007 Posts: 18,157 Mass	After reading some of your feedback, and updates as to what the actual parts are, that are involved in your swap,...IMHO if you want to retain the 2 bolt aluminum F body master, put a booster behind it, and add a proportioning valve to the system, or if manual brakes are your desired goal, then toss the F body master and adapter plate and use a 70 B body or 70-4 E body master designed for manual disc brake application, and add a proportioning valve, if you wish to try/run the B/E body masters, just say so, and I can supply you with the PN# and specs so that you can make an informed choice regarding the proper sizing/application....I'll assume this is for your 69 Coronet? mike

Re: Disc o tech - blues....my 4 wheel drums were better. [Re: DAYCLONA] #1692666 10/31/14 02:41 PM 10/31/14 02:41 PM
Joined: May 2005 Posts: 4,718 Florida BDW master
BDW master Joined: May 2005 Posts: 4,718 Florida	Isn't the factory manual disc/drum set-up a 1 1/16" MC? Can't imagine it would make up the problems mentioned. Why switch back from the nicer 2- bolt set- up?

Re: Disc o tech - blues....my 4 wheel drums were better. [Re: BDW] #1692667 10/31/14 04:48 PM 10/31/14 04:48 PM
Joined: Jan 2003 Posts: 16,376 D dogdays I Live Here
dogdays I Live Here D Joined: Jan 2003 Posts: 16,376	First things first, you need pads that actually work. Sounds like your pads aren't doing the job. They're easy and cheap to switch, unlike some of the other suggestions here. DO the easy things first! Less than $10 at Rockauto. R.

Re: Disc o tech - blues....my 4 wheel drums were better. [Re: dogdays] #1692668 10/31/14 05:53 PM 10/31/14 05:53 PM
Joined: Jan 2003 Posts: 21,067 Niles , Ohio T therocks oh wait.but hey.lets see.oh yeah.
therocks oh wait.but hey.lets see.oh yeah. T Joined: Jan 2003 Posts: 21,067 Niles , Ohio	10 buck pads cant be too good.My ceramics were 30 bucks like 8 years ago and that was shop price.They work better that the Bendix that cost more 15 years ago.Cheap pads are just that cheap period.Saw too many problems with cheap sets at the shop.Rocky Chrysler Firepower

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