![]() |
|
![]() |
#1 |
Registered User
Join Date: Sep 2003
Location: Temecula, Ca.
Posts: 64
|
rear disk conversion
This is my first post, but i've managed to keep my truck running thanks to the experts on this board. I converted my 67 to front disk brakes but my question is what about the rear? I read somewhere that you can use the stock brackets from a 77-79 cady deville. Can I use the stock brackets from a 79-81 eldorado. These type cars I can find. If not, what other type vehicle should I try. I really want to thank all the experts who freely share their knowledge. My wife thinks I'm a genius.
|
![]() |
![]() |
![]() |
#2 |
Account Suspended
Join Date: Feb 2005
Location: Yoncalla Oregon
Posts: 775
|
Converting to rear disk is something I looked into long and hard and decided not to do it. Hooking up a set of calipers and finding a set of rotors is the easy part, correctly biasing your brake system is another completely different problem that can be expensive to do properly. Properly installing an emergency brake in the rear is also another hurdle to overcome.
It can be done ghetto style for a couple hundred bucks, but if you want to do it right and have a completely functioning and properly operating system then it gets pricey. I know there are adjustable proportioning valves available and thats fine if you never load your truck or adjust the bias everytime you drive with a different load. But again this is a truck where the rear end is very light and can easily go into a rear end slide. Can anybody say 360s on a wet stretch of Oregon freeway after a Ferd has cut you off, I can. Something to chew on: The manufacturer didn't offer 4 wheel disk until after they had perfected anti-lock brakes (ABS) this is because the weight of the rear of a truck can vary several hundred pounds depending on the load it is carrying, unlike cars which stay relatively constant. In order to properly bias a trucks brakes you would have to figure out a way of controlling the rear wheel lock-up threshold under all of these load conditions as well as varying road conditions. The ABS system does this and made the switch to 4 wheel disk a no-brainer for GM. Without a computer or automated control system it seems to me that retro fitting a fully functioning system is unadvisable. Just my $.02 |
![]() |
![]() |
![]() |
#3 |
member #16
![]() Join Date: Dec 1999
Location: Yuba City Ca.
Posts: 3,618
|
Heres an article about cad or chev parts. Also I think 9" lincoln diffs have been used. John
http://www.classicperform.com/tech_a...kes-trucks.htm
__________________
john http://67-72chevytrucks.com/vboard/showgroups.php board vendors ![]() http://www.flickr.com/photos/1745471...7602865984234/ Last edited by john; 04-01-2005 at 09:05 PM. |
![]() |
![]() |
![]() |
#4 | |
Got Light Emitting Diode?
Join Date: Apr 2004
Location: Newberg, OR
Posts: 2,485
|
Quote:
__________________
1968 1/2 ton 2wd lwb 6 lug disc and bags up front. Next c notch and rear bags '02 Chevy Silverado LT ext cab short bed 2WD 5/7 drop on 22's ![]() 1993 Cherokee work ride/weekend wheeler |
|
![]() |
![]() |
![]() |
#5 | |
Account Suspended
Join Date: Feb 2005
Location: Yoncalla Oregon
Posts: 775
|
Quote:
Ya gotta luv living between California and Washington, It's like Nascar every damn day. "He didn't hit ya he rubbed ya, and rubbin' is racin son" ![]() |
|
![]() |
![]() |
![]() |
#6 | |
Got Light Emitting Diode?
Join Date: Apr 2004
Location: Newberg, OR
Posts: 2,485
|
Quote:
![]()
__________________
1968 1/2 ton 2wd lwb 6 lug disc and bags up front. Next c notch and rear bags '02 Chevy Silverado LT ext cab short bed 2WD 5/7 drop on 22's ![]() 1993 Cherokee work ride/weekend wheeler |
|
![]() |
![]() |
![]() |
#7 | |
Registered User
Join Date: Dec 2003
Location: Stockton, CA
Posts: 1,579
|
Quote:
![]() ![]() ![]()
__________________
For every person with a spark of genius, There are a hundred with ignition trouble. ![]() |
|
![]() |
![]() |
![]() |
#8 |
Designated A-hole!
Join Date: Mar 2003
Location: South Mississippi
Posts: 36,450
|
Welcome to the board from South Mississippi! What I want to know is how did you go this long without posting?
![]()
__________________
"If it ain't broke, fix it 'til it is!" Being stupid ain't illegal. ![]() We're Still Debt Free Except for the House!!! www.daveramsey.com 70 GMC SWB Stepside project "Green Booger" soon to be 6.0l/4l80e 93 S-10 "Poppaw's Truck" |
![]() |
![]() |
![]() |
#9 |
Senior Member
![]() Join Date: Mar 2004
Location: Somewhere
Posts: 985
|
here's what i'm going to go with:
![]() http://www.steeltechsolutions.com/RE...PAGE_CODE.html the brackets are $89 and use the same rotors and calapers as everyone elses. i figure why buy a kit when i can build one by going to carquest or autozone for half the price. ondrew Last edited by roj2323; 04-01-2005 at 09:50 PM. |
![]() |
![]() |
![]() |
#10 |
Join Date: Dec 1999
Location: Eastern - Manitoba Canada, Winnipeg
Posts: 4,369
|
Welcome and here's some info and links.
![]() Haven't looked up how this swap works in a while but its Cadillac Seville maybe 77-79 era parts you want as it give you an emergency brake cable option that way also. Anyway I had some of these swap pages book marked and there still good..so happy reading. one says use seville the other for cars says use deville..so whatever works. There are kits, but hey, I like scronging around a little. ![]() http://www.geocities.com/motorcity/6765/page11.html http://home.pacbell.net/bigiron/Arti...rRearDisc.html
__________________
Senior active founding member. 70 3/4 ton GMC Suburban 4x4 250/4 spd. 71 1/2 ton Suburban Chevy 4x4, 350/350 72 Chev 1 ton tow truck 402BB w/Holmes 440 wrecker on propane 2005 FLSTSCI Harley Springer 85 FXSB Harley Lowrider 72 Triumph 650 Bonneville 5spd "Poor people don't have hobbies" Quote from wife. |
![]() |
![]() |
![]() |
#11 |
Registered User
Join Date: May 2000
Location: Petrolia,Ontario,Canada but working in Port Huron,Mi.
Posts: 1,771
|
Here's a parts list for when I did my rear disc brake swap onto my 71 Blazer.
Master cylinder-1978 Corvette Napa part # UBP39052 non-napa part#m82071 $81.49,no core charge Dual diaphram booster(no really needed but I put one on) Napa part# 5471007-$113.99 $4.00 core charge. TSM rear brake kit. Includes rear disc mounting brackets,redrilled rotors and short rubber brake lines. Part# 2531 $239.95 Stainless flexable lines are available for $50.00 extra part # 3702-8 Rear disc brake calipers with integral emergancy parking brake for a 1984 Cadillac Eldorado Auto Zone part # C243 and C242(remanafactured) $39.99 each with $80.00 core charge. Proportioning valve- 1984 Cadillac Eldorado Obtained from auto wrecker for less than $10.00(free if you stick it in your pocket) ![]() ![]() ![]()
__________________
71 blazer,350SBC,approx.375HP,700R4,factory GM TPI.Dual electric fans,33x12.5x15 ATR on stock suspension. Petrolia,Ontario,Canada but working in Port Huron,MI. See ALL my Blazer pic's HERE |
![]() |
![]() |
![]() |
#12 |
'70 GMC C-25 LWB
Join Date: Oct 2004
Location: Binghamton, N.Y.
Posts: 273
|
Hey screamin, what's up... (DTerry's dad again)
I don't disagree with your post, in fact for a long time I kinda thought the same way. But then I got thinking about the fact that there are drums in the back - and that doesn't cause problems. The drums don't have any sort of load compensating device. There is a proportioning valve on both disc and drum setups, and I realize those valves are different for each. They both just proportion the pressure allocated to the rear. So what gives? There must be something I'm missing. I can tell you that on our race car, where we know the exact weights, and test brake bais regularly, it (rear discs) makes a huge difference (good thing). We have an adjustable bias controller. I'm not saying that the controller we have is good on the street (and would not recommend one - too dangerous) My thought is that until the manufactures came up with anti-lock or load compensators (chevy, maybe others) everyone just lived with the fact that trucks had brake issues with load variations. Thoughts anyone?
__________________
1970 GMC C-25 LWB (middle of frame up) 5-7 drop with 3in drop spindles, flip kit with blocks and still keeping the 3/4 ton. Shaved drip rails and marker lights, rear roll pan, cowl induction hood. 1987 Camaro z28 350, vortec 305 heads. 10:1 comp, t5 trans. Street terrrorizer. 1988 Monte Carlo (Super Stock ashpalt race car) My Truck |
![]() |
![]() |
![]() |
#13 |
Registered User
![]() Join Date: Aug 2001
Location: SOMERSET KY.
Posts: 6,427
|
![]() SCEAMIN_C10.....THIS IS THE FIRST TIME I'VE EVER HEARD OF ANYONE EVER SAYING THAT DRUMS WERE BETTER. ![]() ![]() ![]()
__________________
junkyardjohn 69 1 TON TOW TRUCK // 84 4WD CUCV BLAZER// 85 1 TON 4WD STAKE TRUCK// 86 M1031 5/4 TON 4WD CUCV// ALOT OF OLD TRUCKS FOR ONE OLD MAN TO DRIVE. ![]() LIFE MEMBER OF P.E.T.A (PEOPLE EATING TASTY ANIMALS) DON'T RENT U-HAUL ALWAYS TELL THE TRUTH IT WILL AMAZE PART OF THE PEOPLE & ASTONISH THE REST |
![]() |
![]() |
![]() |
#14 | |
Account Suspended
Join Date: Feb 2005
Location: Yoncalla Oregon
Posts: 775
|
Quote:
I don't recall saying that drums are better than disks, I suggest you re-read the post, and refrain from putting words in my mouth. I said in a nutshell that unless you spend a few bucks and know exactly what you are doin then leave well enough alone. Disks are a better setup than drums for most occasions, but only if properly designed into a system. I think it unwise to "rig" a braking system together and take your own and other peoples lives in jeopardy on the interstate. I live in a state full of hillbilly's (present company excluded) and NO inspections. You ought to see the sh!t on the road here, usually 'cause Bubba thought it was a good idear, his 9th grade education outways the PHD that originally designed the system. I also stated that if you design the system into a vehicle that will not vary alot in rear end weight ie. cars, blazers, trailer queen trucks, and what not thaen you could probably get away with it safely on the cheap (brackets, calipers, proportioning valve, and MC) This may have been the first time you thought you heard drums are better than disks. This is not a black and white "Drums good/ Disk bad" statement. There are certain conditions in which both have outstanding attributes. Drums fade and don't grab as well as disks in panic stops, I would prefer that in the rear of a non ABS truck. As far as adjusting your driving style, that is a load of crap in my book. There is no time to adjust anything in a panic situation. You either give it the brake, give it the gas, or take the ditch. Your vehicle should be ready for either of the first two. Brakes are not something you screw with, especially if you are a novice. Just my $.02 By the way, the Caps Lock key is on the left side of the keyboard, consider yourself enlightened. ![]() Last edited by screamin_c102; 04-03-2005 at 03:36 PM. |
|
![]() |
![]() |
![]() |
#15 |
Registered User
![]() Join Date: Aug 2001
Location: SOMERSET KY.
Posts: 6,427
|
[QUOTE=screamin_c10]I don't recall saying that drums are better than disks, I suggest you re-read the post, and refrain from putting words in my mouth.
I said in a nutshell that unless you spend a few bucks and know exactly what you are doin then leave well enough alone. Disks are a better setup than drums for most occasions, but only if properly designed into a system. I think it unwise to "rig" a braking system together and take your own and other peoples lives in jeopardy on the interstate. I live in a state full of hillbilly's (present company excluded) and NO inspections. You ought to see the sh!t on the road here, usually 'cause Bubba thought it was a good idear, his 9th grade education outways the PHD that originally designed the system. /QUOTE] I THINK YOURE ABSOLUTLEY RIGHT .... I THINK PEOPLE THAT HAVE ABSOLUTELY NO IDEA (OR AS YOU & BUBBA WOULD SAY "IDEAR) HOW A BRAKING SYSTEM OPERATES SHOULD LEAVE THE BRAKING SYSTEM ALONE. I NEVER RECOMENDED "RIGGING" A SYSTEM. (PLEASE REFRAIN FROM PUTTING WORDS IN MY MOUTH) THE ORIGINAL DESIGN OF THESE TRUCKS IS OVER 40 YEARS OLD, & BELIEVE ME... THEY HAVE IMPROVED SINCE THEN. I DONT HAVE ANY CONTROLL OVER THE WAY PEOPLE "RIG" VEHICALS UP BY YOU. FOR YOU TO COME OFF LIKE YOU DO AFTER BEING ON THIS BOARD LESS THAN A MONTH , SAYS AN AWFUL LOT ABOUT YOU. I HAVE A REASON FOR TYPING IN ALL CAPS, BUT SEEING AS HOW YOU'VE BEEN ON HERE FOR LESS THAN A MONTH.. I GUESS YOU WOULDN'T KNOW NOW WOULDYA. MAYBE YOUR TRUCK WASN'T RANDOMLY VANDELIZED, BUT HAD THE SH!T KICKED OUT OF THE TAILGATE, AS A RESULT OF YOU'RE SPARKELING PERSONALITY. AFTER ALL.. YOU JUST CALLED EVERYONE IN YOU'RE STATE A BUNCH OF MOUTH BREATHING, INBREAD JED HILLBILLYS (MOST CALLED BUBBA) EXCEPT YOU OF COARSE. OH WELL .. WELCOME TO THE GREATEST TRUCK BOARD ON EARTH. STICK AROUND. EVEN THE MOST EXPERIANCED & KNOWLEDGABLE PERSON ON THESE TRUCKS CAN LEARN SOMTHING. ![]() ![]()
__________________
junkyardjohn 69 1 TON TOW TRUCK // 84 4WD CUCV BLAZER// 85 1 TON 4WD STAKE TRUCK// 86 M1031 5/4 TON 4WD CUCV// ALOT OF OLD TRUCKS FOR ONE OLD MAN TO DRIVE. ![]() LIFE MEMBER OF P.E.T.A (PEOPLE EATING TASTY ANIMALS) DON'T RENT U-HAUL ALWAYS TELL THE TRUTH IT WILL AMAZE PART OF THE PEOPLE & ASTONISH THE REST |
![]() |
![]() |
![]() |
#16 | |
Account Suspended
Join Date: Feb 2005
Location: Yoncalla Oregon
Posts: 775
|
Quote:
![]() I didn't realize I was gettin' bashed around on this one so much ![]() I figured the guy is young, has a wife (maybe a kid) and lives in California. ![]() Thanks again....Bill |
|
![]() |
![]() |
![]() |
#17 |
68cst_ss490
Join Date: May 2001
Location: edmonton,canada
Posts: 1,363
|
a little tid bit on disc brakes for ya
Though disc brakes rely on the same basic principles to slow a vehicle (friction and heat), their design is far superior to that of drum brakes. Instead of housing the major components within a metal drum, disc brakes use a slim rotor and small caliper to halt wheel movement. Within the caliper are two brake pads, one on each side of the rotor, that clamp together when the brake pedal is pressed. Once again, fluid is used to transfer the movement of the brake pedal into the movement of the brake pads. But unlike drum brakes, which allow heat to build up inside the drum during heavy braking, the rotor used in disc brakes is fully exposed to outside air. This exposure works to constantly cool the rotor, greatly reducing its tendency to overheat or cause fading. Not surprisingly, it was under racing circumstances that the weaknesses of drum brakes and the strengths of disc brakes were first illustrated. Racers with disc brake systems could carry their speed "deeper" into a corner and apply greater braking force at the last possible second without overheating the components. Eventually, as with so many other automotive advances, this technology filtered down to the cars driven by everyday people on public roads.
__________________
Dean edmonton,canada a winter wonderland 2005 Chevrolet Avalanche LT cold air intake, performance exhaust, Comp cams cam, jba shorty ceramic headers. http://www.cardomain.com/ride/3090973 |
![]() |
![]() |
![]() |
#18 |
Registered User
Join Date: May 2000
Location: Frankfort, Kentucky, USA
Posts: 2,163
|
Here is my setup. I took the entire rear out of an old Imperial with rear discs. There rear end is one hefty peice. Draw backs are I had to redrill the axles for the truck bolt pattern, weld on saddles, and the rotors and parking brake parts are discontinued. Didn't know that till after I bought it, but i've got good stuff now, so I should be alright. I originally went that route to have rear discs and have something that I could get parts for at any auto parts place. If I did this over again, i'd use a Lincoln rear end, cuz they have discs, 5 on 5 pattern, closer to same width, and you order a stump built however you want and bolt it straight in. Live and learn.
What is meant by load variations? You mean haulin stuff? What difference does disc or drum make? Friction is friction. If the rear is set so they don't lock up unloaded, then any additional load on the rear would give the tires more bite and you should be able to apply more pedel pressure without them locking. Whenever you haul anything they brake, steer, and handle different, so you adjust with your driving right?
__________________
'69 CST Short fleetside Lowered, 400 small block, 700R4, 4 wheel disc brakes, front sway bar & rear camaro sway bar (in progress) '87 V10 4x4 Short Fleetside Quad Suspension and Dual Tanks |
![]() |
![]() |
![]() |
#19 | |
'70 GMC C-25 LWB
Join Date: Oct 2004
Location: Binghamton, N.Y.
Posts: 273
|
Quote:
I don't know how other newer trucks did it (excluding anti-lock). In my opinion, disk brakes work a whole lot better, and if you install the correct proportioning valve, it's a good idea. The catch here is "the correct proportioning valve" because nobody ever made one for trucks without some sort of antilock or load compesation device. You'll need to do some research to find one close to what you need (depends on what the parts came from). I think that screamin_c10 is absolutely correct in his statement on this, and you should consider his advice. But if you don't plan on hauling alot, or you're confident you can adjust your driving style, or you can find a proportioning valve (maybe adjustable - I don't advise it) that works... go for it. One last thing, unless I'm miss interpreting something, nobody said that drums are better than disc's.
__________________
1970 GMC C-25 LWB (middle of frame up) 5-7 drop with 3in drop spindles, flip kit with blocks and still keeping the 3/4 ton. Shaved drip rails and marker lights, rear roll pan, cowl induction hood. 1987 Camaro z28 350, vortec 305 heads. 10:1 comp, t5 trans. Street terrrorizer. 1988 Monte Carlo (Super Stock ashpalt race car) My Truck |
|
![]() |
![]() |
![]() |
#20 |
just can't cover up my redneck
Join Date: May 2004
Location: Columbus OH
Posts: 11,414
|
I will....... with a few qualifications "drums are better than discs". As far as pedal effort to braking power drums are better. Discs are the reason that power boosters were added. It take far more line pressure to operate disc brakes. Drums are "self-energizing", so the pedal pressure doesn't have to increase as much to shorten stopping distance. It is kind of like a snowball rolling down a hill.........it takes less additional pressure to increase stopping power.
Drums don't have the fading with heat problems or the wet performance problems of discs either. Look at dump trucks and semi trucks/trailers. The real advantage of disc brakes has to do with the lazy and mechanically inept average driver. They are far more forgiving as far as adjustment and mechanically simpler. Disc brakes were first used in the front of cars to combat the "pulling during braking" that improperly adjusted drums can cause. Personally I am not sold on the concept of discs on the rear....especially if you are expecting better stopping. They may look great...if that is all you are looking for. I'm not saying don't do it, it can be done, and done safely...just don't expect a great difference in stopping power. Discs will clean better on a 4x4 but they will act odd (slippery) when the are wet. I do remember working on many mid/late 80's trucks with the self adjusting rear proportioning valve. The main thing about it at the time is that it had to be adressed when lifting 4x4s. |
![]() |
![]() |
![]() |
#21 | |
Registered User
![]() Join Date: Aug 2001
Location: SOMERSET KY.
Posts: 6,427
|
Quote:
Drums don't have the fading with heat problems or the wet performance problems of discs either. Look at dump trucks and semi trucks/trailers. I GUESS YOU'VE NEVER DRIVEN A DRUM BRAKE VEHICAL THRU A BIG WATER PUDDLE?? The real advantage of disc brakes has to do with the lazy and mechanically inept average driver. THAT DOESN'T EVEN JUSTIFY A REPLY ![]() ![]() ![]() with a few qualifications "drums are better than discs". EVERYONE IS ENTITLED TO THERE OWN OPINION.... AFTER ALL... ALOT OF PEOPLE THOUGHT PENICILLIN WAS BAD JU JU & FROM THE DEVIL .. BUT IT TURNED OUT O-K. ![]() ![]() ![]() SORRY BUT I'LL STILL HAVE TO CALL B/S ON YOUR WHOLE ARGUMENT
__________________
junkyardjohn 69 1 TON TOW TRUCK // 84 4WD CUCV BLAZER// 85 1 TON 4WD STAKE TRUCK// 86 M1031 5/4 TON 4WD CUCV// ALOT OF OLD TRUCKS FOR ONE OLD MAN TO DRIVE. ![]() LIFE MEMBER OF P.E.T.A (PEOPLE EATING TASTY ANIMALS) DON'T RENT U-HAUL ALWAYS TELL THE TRUTH IT WILL AMAZE PART OF THE PEOPLE & ASTONISH THE REST Last edited by junkyardjohn; 04-03-2005 at 10:54 AM. |
|
![]() |
![]() |
![]() |
#22 |
Questionable
Join Date: Mar 2005
Location: Atlanta
Posts: 13,376
|
Anyone have a picture showing how the brake lines are run naturally in the rear for one of our trucks? It looks like BobbyK welded some brackets to hold the lines in his. I don't know if I would be comfortable doing the same with mine knowing it's so close to the u-bolts and my truck is going to be so low to the ground.
__________________
If I've got anything up for grabs, it'll be here: 7-hole gauge cluster for a 67-72 p/u FREE (link) I can't check the forum daily. If I don't reply to you within 24 hours, drop me a PM! I'm (hopefully) still alive and will reply faster to a PM. |
![]() |
![]() |
![]() |
#23 |
Registered User
![]() Join Date: Dec 2004
Location: Gypsum Kansas 67448
Posts: 1,681
|
i love the rear disc brakes.i have them on mine,and would never ever go back to drums,you can do it cheap,or u can put a couple of dollars into it,it just depends what your budget will let u do.but i have had nothing but good luck out of mine,this damn thing stops on a dime
__________________
21 2500hd duramax 58 apache HILLJOB GRAPHIX--for all your graphic needs My build thread http://67-72chevytrucks.com/vboard/s...d.php?t=542497 LS ENGINE SWAP INFORMATION THREAD http://67-72chevytrucks.com/vboard/s...d.php?t=377348 4l60 to an NP205 http://67-72chevytrucks.com/vboard/s...43#post3697343 |
![]() |
![]() |
![]() |
#24 | |||
just can't cover up my redneck
Join Date: May 2004
Location: Columbus OH
Posts: 11,414
|
Quote:
Quote:
I didn't say that drums were perfect, I even listed some disadvantages, but the point still prevails most big trucks are drum and may have discs on the front. Quote:
W/O your power booster your discs would get old pretty quickly. I didn't blanketly state that drums were better, just that there is certainly nothing wrong with them and that there is no stopping advantage to rear discs. Rear discs are purely a bling thing............nothing wrong with that either. |
|||
![]() |
![]() |
![]() |
#25 |
Account Suspended
Join Date: Jun 2000
Location: over yonder
Posts: 14,270
|
The ORIGINAL reaon the car manufacturers switched to disc brakes is pure economics. There are less parts in a disc brake system versus a drum brake system.
|
![]() |
![]() |
![]() |
Bookmarks |
Thread Tools | |
Display Modes | |
|
|