Viper Conversion Kit For 11.75 Rotors

This AR Engineering kit allows you to use the high technology Viper caliper on the factory 11.75 inch diameter rotor. The Viper caliper is lighter than the factory cast iron caliper and it provides better braking feel due to the four piston design. Since the Viper caliper is a modern high performance design, the pad selection is quite broad. This kit works with the front calipers from any 2002 or earlier Viper.

The AR Engineering kit contains the brackets and pad spacers necessary to hang the Viper calipers onto ’73 to ’76 A body drum brake knuckles. These knuckles will fit any 1962 to 1972 B body, and any E body car. They will also fit earlier A body cars if the upper control arm is changed to the ’73 or later style.

The Viper calipers can be purchased new from any Dodge dealer, or you might find them for sale used. AR Engineering does not sell these calipers. You will also need to acquire the proper pads, the Viper caliper mounting bolts and suitable brake hoses.

The AR Engineering brackets come pre-assembled so all that is required is to bolt the brackets onto the knuckles. Use the supplied 3/8 flathead bolts to attach to the knuckle as shown. The lower attachment is made by re-using the existing lower ball joint bolts. Tighten the lower ball joint bolts to the specification called out in your service manual. (usually 125 ft-lbs for B or E body cars). The 3/8 diameter bolts should be torqued to 45 ft-lbs.

The AR Engineering Viper conversion kit uses the late B body rotor. These rotors are 11.75 inches in diameter and 1.00 inches thick. They came factory installed from 1976 to 1979 on cars such as the Cordoba, Charger and Fury.

Since the Viper caliper is designed for a 1.250 thick rotor, pad spacers need to be installed behind the pads when used on the 1.00 thick B body rotor. These pad spacers simply slide in behind each brake pad and are retained by the pad retention pins. WARNING - Do not put the pad spacers between the rotor and the pad! If you do that, your brakes will not work. The pad must be contacting the rotor.

We recommend hanging the Viper calipers to the rear of the knuckle since that is the way they are originally designed to work. If you front mount them, the crossover tubes will need to be relocated to the bottom so that the bleeders are at the top. The Viper calipers come in passenger or driver side configuration and they must be mounted on the correct side. They cannot be swapped from side to side since they use differential piston sizes to even out pad wear. When installed correctly, the 38 mm piston is the leading one (bottom piston when rear hung, top piston if front hung) while the 42 mm piston is trailing. If you mount them incorrectly, the pads will wear in a taper shape.

The AR Engineering kit is designed to use the factory Viper caliper mounting bolts. Those bolts are not supplied in the AR kit so you’ll need to source them at the same time you buy the Viper calipers. The Mopar part number for the bolts is 6101 964. These factory bolts are designed for an installed torque of 85 ft-lbs.

This picture shows the hose routing as well as the pad spacers properly installed. We recommend Goodridge hoses since they are DOT compliant and reasonably priced. www.goodridge.net  The hose in this illustration is a 17 inch Goodridge part with a 20 degree banjo fitting on the caliper end. Part number for this hose is D330317. The banjo bolt is a 10x1mm bolt. The factory Viper bolt is too long to work with the narrow Goodridge banjo fitting, but it can be cut down in length. In this application we used a new bolt from Goodridge, part number 992-03-31P. There is also an adapter mounted on the frame that converts the brake line flare fitting to a #3 braided hose fitting. This is Goodridge part number FM10324-03P. All of these parts came from Oil Filter Service in Portland OR. www.oilfilterserviceco.com Their phone number is 1-888-232-5126 if you cannot find a local source for Goodridge products.

As shown above, the Viper conversion kit comes with two mounting brackets and hardware, as well as the necessary pad spacers. All parts are made from cold rolled steel and then zinc plated for corrosion protection.  A good source for slightly used Viper calipers and pads is Archer Racing. www.archerracing.com

The Viper caliper is larger than the factory caliper and may cause interference with your existing wheels.  Many original 15 inch wheels will fit this kit but some will not.  In general, wheels from late model cars that came with disc brakes will fit while wheels from earlier drum brake cars will not.  From what we have seen, the 15 inch "cop car" wheels will fit as will the 15x7 JJ wheels from late model disc brake cars.  We have also been told by customers that the 15x7 rallye rims from Wheel Vintiques will fit if a thin spacer is used.  The best plan is for the customer to test fit a rim after installing the Viper kit and to carefully observe for any interference.  Rims are mass produced and may vary from batch to batch so make sure that your rims do clear the calipers before driving.