DISC BRAKE COVERSION

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Frankenchevy

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All this is my opinion and you can tell me to suck it if you like. Half of the cars/trucks I build I do rear conversions, but only if it adds up.

Other than wet environment there is almost no benefit on the rear.

Pros:
Easier to change pads then drums

Possible braking improvement but since your rears do about 30-40% of the braking and unless you are upgrading to a 14" rotor and 4-6 piston $3k rear set-up, you'll only get a maybe a 10-20% over a drum, the net return will be maybe, maybe 3-5% better. Only in the right environment. If you tow, you'll overheat a small pad much quicker than a large shoe.

Cons:
Ineffective parking brake on most set-ups.

Rear disc suffers from knock back issues unless it's a full float. Have to drag or pump brakes to keep pad to disc if road racing.

Reduced gas mileage. Disc brakes usually outweigh drums when you add up bracket, calliper, rotor. Increased unsprung weight and more rolling resistance as pads frequently in contact.

Increased lining changes. How often you change shoes vs. Pads? I would bet 2-3x as much.



Racing-yes
Off-road only-yes
Rain every day and you don't know how to pump-yes

Daily driver-no

If it's a 1/2 ton. Better return is the larger 1/2 ton drum set-up. Increased performance without all the hassle. Cost $50-100 at junkyard and another $100 for all new parts for it.
There’s no way my 14ff cucv brakes outweighed my disc conversion. All of the disc components are less than half the weight of my drums alone.

edit: now I see you’ve already addressed this point.
 

Rhett Croley

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I have them on a 14ff and two 14sfs. They look great but not worth the trouble. I have lock-up issues on the rear after changing to hydro boost, even with the prop valve turned all the way down on the 14ff. The 14sf has el dorado calipers and they were a **** to bleed and set up and I beleive they are the reason for the pulsation I feel in that truck's brakes. My research through indicates is that this is common and I'm going to have to go to half ton front calipers instead of el dorados to make it stop.
 

Ricko1966

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Was that title supposed to read disc brake coercion?
 

84 M1008

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Maybe disks weigh more on a 1/2 ton axle,not sure,but I know I’m about 75 lbs lighter on the full float 14 bolt with out drums...

I did the conversion on my M1008/K30 and there was no way the disc conversion out weighs the gigantic drums on that truck.
 

LSX K10

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I did a conversion on the rear of my 86 k10 from Little Shop MFG using wilwood calipers and drilled slotted rotors. Love it so far but haven’t finished the truck yet. Here’s a pic of front and rear
 

Keith Seymore

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All this is my opinion and you can tell me to suck it if you like. Half of the cars/trucks I build I do rear conversions, but only if it adds up.

Other than wet environment there is almost no benefit on the rear.

Pros:
Easier to change pads then drums

Possible braking improvement but since your rears do about 30-40% of the braking and unless you are upgrading to a 14" rotor and 4-6 piston $3k rear set-up, you'll only get a maybe a 10-20% over a drum, the net return will be maybe, maybe 3-5% better. Only in the right environment. If you tow, you'll overheat a small pad much quicker than a large shoe.

Cons:
Ineffective parking brake on most set-ups.

Rear disc suffers from knock back issues unless it's a full float. Have to drag or pump brakes to keep pad to disc if road racing.

Reduced gas mileage. Disc brakes usually outweigh drums when you add up bracket, calliper, rotor. Increased unsprung weight and more rolling resistance as pads frequently in contact.

Increased lining changes. How often you change shoes vs. Pads? I would bet 2-3x as much.



Racing-yes
Off-road only-yes
Rain every day and you don't know how to pump-yes

Daily driver-no

If it's a 1/2 ton. Better return is the larger 1/2 ton drum set-up. Increased performance without all the hassle. Cost $50-100 at junkyard and another $100 for all new parts for it.


As a former brake engineer for GM Truck (and having given this a lot of thought): That's kind of where I'm at.

The rears are throttled down via the proportioning valve. If one needs more rear brake, why wouldn't you just kick up the line pressure to the rear?

Otherwise, putting discs on is like putting in a bigger motor to overcome a 2bbl carb, at least the way I see it.

K
 
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Bennyt

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For those of you do decide to put discs on the rear on lifted trucks, I prefer to mount them upside down with the bleeders facing down. You'll have to bleed them off the truck with a piece of wood in the caliper, but you'll be able to run the parking brake cables over the axles for better ground clearance possibly eliminating cable extensions and or custom cables.
 

BBBURB

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My back brakes where not working at all. They were leaking, the axle seal was bad, they needed a complete overhaul. I said to myself, I am not overhauling this trash. If I am going to spend my precious time on getting some rear brakes working its going to be upgraded. Also im in California where "brake checking" happens every mile or so. It took me about 3 days to do this job. It was a total PITA but Im happy now. I stop on a dime. I opted for the giant caliper rather than the Cadillac Caliper with e brake. Im telling you, I can stop on a dime. Very happy. Product from Lugnut 4x4 who was very supportive by email when I had some install problems not related to his product. I do need to dial down the brake pressure so it doesnt overpower the fronts. But im enjoying it for now as is.



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BBBURB

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For those of you do decide to put discs on the rear on lifted trucks, I prefer to mount them upside down with the bleeders facing down. You'll have to bleed them off the truck with a piece of wood in the caliper, but you'll be able to run the parking brake cables over the axles for better ground clearance possibly eliminating cable extensions and or custom cables.

The reason the bleeders are supposed to be at the top is because air bubbles rise up. It makes it easier to bleed the brakes and not have trapped air bubbles.
 

Curt

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The reason the bleeders are supposed to be at the top is because air bubbles rise up. It makes it easier to bleed the brakes and not have trapped air bubbles.

I believe he knows,just trying to give out pointers to help with ground clearance and protect the parking brake.
 

Powerhouse Ranch

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The reason the bleeders are supposed to be at the top is because air bubbles rise up. It makes it easier to bleed the brakes and not have trapped air bubbles.

Always remember that! haha learned that the hard way on an early 2000s POS Ford PowerJoke at work one time. Flippin gay setup i'll tell ya. I swear Ford just likes them boys i don't know what else to tell ya
 

Powerhouse Ranch

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I did the conversion on my M1008/K30 and there was no way the disc conversion out weighs the gigantic drums on that truck.

oh i'm sure that made those sexy trucks 200% sexier
 

Bennyt

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I believe he knows,just trying to give out pointers to help with ground clearance and protect the parking brake.


Correct. Thank you sir!
 

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