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Weld-On Rear Disc Brake Kit, 1978-88 GM Caliper, 3 Inch Backspace

Specs
Centerline of Holes:
5.50
Material Type:
Cast Iron
Sold in Quantity:
Kit
Finish:
Natural
Bolt Pattern:
Multi: 5 on 5"/4.75"/4.50"
Thread Pitch:
7/16"-20
Hardware Included:
Yes
Rotor Diameter:
11.75
Caliper Pistons:
Single
Rotor Thickness:
.81
Caliper Finish:
Natural
Parking Brake Provision:
No
Rotor Construction:
Vented
Rotor Hat Bolt Pattern:
8 x 7.00"
Garage Sale:
No
Rotor Location:
Rear
Rotor Shape:
Round
Drilled:
No
Slotted:
No
Notes
Includes rotors, rotor hats, caliper brackets, calipers, pads, and hardware.
Weld-On Rear Disc Brake Kit, 1978-88 GM Caliper, 3 Inch Backspace

Click image to enlarge

Please NOTE the following about this product:

  • This item is sold as a kit.

Details

Reviews

Q & A

What's in the Box

Replace those old drum brakes with modern rear disc brakes. Mounts .81" x 11-3/4" Pro-lite vented iron rotors and calipers to 3" tube rear end. Complete with rotors, hats, metric calipers (7/16"-20 inlets), brackets, brake pads, caliper brackets and slider bolts. 

Steel hat fits 5 lug hubs with 4-1/2", 4-3/4", or 5" bolt circle.

910-31931 Instructions (PDF)

Specs

  • Caliper Brackets (2)
    • Weld onto a 3" axle tube
  • Rotors (2)
    • GM-style .81" x 11-3/4", 8 on 7" bolt pattern
    • Straight vanes, 8 lbs. each
  • Rotor Hats (2)
    • Stamped steel, 3" backspace
    • 3.06" center hole, 6-1/4" I.D., 1/2" stud holes, 2 lbs.
  • Rotor Bolt and Nut Kit (2)
  • Caliper Slider Bolts (4)
  • Brake Pads (2 sets)
    • Street compound, little metallic, long rotor and pad life
  • Calipers - 1978-88 GM Metric (L & R)
    • 7/16"-20 inlet
    • Cast iron body, 2.38" single piston
    • Saves 3.5 lbs. per side compared to '69-'77 GM calipers

Customer Reviews

Rated 4 out of 5 by 2 reviewers.
RATING BREAKDOWN
2 reviews
5 Stars
0
4 Stars
2
3 Stars
0
2 Stars
0
1 Star
0
RECOMMEND THIS PRODUCT:

mean green
Verified Purchaser
chehalis wa
Product Rating

all in all a good kit

August 31, 2011
the only issue i had with this kit is that it was missing some of the clips for the pads.
No, I would not recommend this product.
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Was this review helpful? 0 0

elcomeano
Verified Purchaser
Fostoria, OH
Product Rating

does a great job

February 04, 2011
used this item on my drag car... I did have to grind on the caliper so the wheel didn't hit it.
Pros:
  • Lightweight
  • Decreased Stopping Distance
  • No Fade
Yes, I recommend this product.
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Page 1 of 1

Product Q&A

7 questions : 7 answers

Is there a option for drilled and slotted rotors with this kit? Is there a option to upgrade to drilled and slotted rotors with this kit?

1 answers
nate31
Kokomo
December 19, 2014

Is there a option for drilled and slotted rotors with this kit? Is there a option to upgrade to drilled and slotted rotors with this kit?

Answers

December 20, 2014
EricM
We offer drilled rotors 10698506121 or slotted rotors 1066640104 and 1066640105 that can be substituted into this kit for the difference in the cost of the rotors. We do not recommend drilled rotors on street vehicles. Drilled rotors will certainly crack and must be inspected on a frequent basis. When rotors crack it can cause catastrophic failure.

will this kit work with 15" wheels

1 answers
x37v
June 11, 2014

will this kit work with 15" wheels

Answers

June 12, 2014
EricM
Yes this kit will work with 15" or larger wheels.

will this work on a 1964 impala

1 answers
jeremiah47j
March 25, 2014

will this work on a 1964 impala

Answers

March 26, 2014
EricM
Yes this kit should work on a 64 Impala but you will want to measure to be sure that the 3" offset of the steel hats provided in this kit will locate the caliper so that it has clearance to the frame, suspension, and bracketry on your rear end. Also the flange on your axle can be no larger than 5 3/4" OD for the hat to fit over it.

What is the torque spec on the 5/16 bolts that hold the rotor on? Should the nuts face in or out? A picture in the instructions would be a LOT of help

1 answers
victor906
Gladstone, MI, USA
August 06, 2013

What is the torque spec on the 5/16 bolts that hold the rotor on? Should the nuts face in or out? A picture in the instructions would be a LOT of help

Answers

August 07, 2013
Jason
The recommended torque value for 5/16-24 socket head bolts is 30 foot pounds dry and 26 foot pounds if oiled. The bolts can be installed from either direction.

Is this kit fits on my chevy 80 with dana 30 axle?

1 answers
Garagem39
February 10, 2013

Is this kit fits on my chevy 80 with dana 30 axle?

Answers

February 11, 2013
Jason
This weld on disc brake kit will work with rearends that have 3" axle tubes.

Can this rear disc brake fit a 1974 Vega with 5 lug 4 3/4 inch axle? Does it come with a parking brake and can the disc /calipers be reduced to 9 or 10 inch disc?

1 answers
August 10, 2011

Can this rear disc brake fit a 1974 Vega with 5 lug 4 3/4 inch axle? Does it come with a parking brake and can the disc /calipers be reduced to 9 or 10 inch disc?

Answers

August 12, 2011
John
These kits come as pictured in our catalog and on the website. Only available with the 11 ¾” rotors and the center hat is tri patterned for bolt pattern. If wanting an E-brake application we offer kits number 91031933 or 91031934 with similar looks and function but with the E brake calipers. We have several other bolt on brake kits available also to ease assembly and eliminate the weld on brackets if interested.

Can I get a hat with a 5 lug on 5.5" hole circle?

1 answers
AAshby
April 10, 2015

Can I get a hat with a 5 lug on 5.5" hole circle?

Answers

April 13, 2015
EricM
Sorry we do not offer brake hats for 5 on 5.5" bolt circle.
Page 1 of 1

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