Additional information and recommendations, Balancing the brake bias on 4 wheel disc vehicles – Wilwood Forged Narrow Superlite 6R Big Brake Front Brake Kit (Hub) User Manual

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Additional Information and Recommendations

•Fill and bleed the new system with Wilwood Hi-Temp° 570 grade fluid or higher. For severe braking or sustained high heat operation,

use Wilwood EXP 600 Plus Racing Brake Fluid. Used fluid must be completely flushed from the system to prevent contamination.
NOTE: Silicone DOT 5 brake fluid is NOT recommended for racing or performance driving.

•To properly bleed the brake system, begin with the caliper farthest from the master cylinder. Bleed the outboard bleed screw first, then

the inboard. Repeat the procedure until all calipers in the system are bled, ending with the caliper closest to the master cylinder.
NOTE: When using a new master cylinder, it is important to bench bleed the master cylinder first.

•If the master cylinder is mounted lower than the disc brake calipers, some fluid flowback to the master cylinder reservoir may occur,

creating a vacuum effect that retracts the caliper pistons into the housing. This will cause the pedal to go to the floor on the first stroke
until it has “pumped up” and moved all the pistons out against the pad again. A Wilwood in-line two pound residual pressure valve,
installed near the master cylinder will stop the fluid flowback and keep the pedal firm and responsive.

•Test the brake pedal. It should be firm, not spongy and stop at least 1 inch from the floor under heavy load.

If the brake pedal is spongy, bleed the system again.

If the brake pedal is initially firm, but then sinks to the floor, check the system for fluid leaks. Correct the leaks (if applicable) and
then bleed the system again.

If the brake pedal goes to the floor and continued bleeding of the system does not correct the problem, a master cylinder with
increased capacity (larger bore diameter) will be required. Wilwood offers various lightweight master cylinders with large fluid
displacement capacities.

NOTE: With the installation of after market disc brakes, the wheel track may change depending on the application. Check your wheel

offset before final assembly.

•On some models of disc brake spindles there are “ears” where the OEM calipers were mounted and these “ears” interfere with the

assembly of the Wilwood disc brake kit. If it becomes necessary to remove these “ears”, remove as little as possible being careful not
to cut away any of the mounting holes that may be required to bolt on the caliper mounting bracket.

•If after following the instructions, you still have difficulty in assembling or bleeding your Wilwood disc brakes, consult your local chassis

builder, or retailer where the kit was purchased for further assistance.

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Balancing the Brake Bias on 4 Wheel Disc Vehicles

OE Style or Single Mount Race Pedal with Tandem Outlet Master Cylinder:

Front to rear caliper piston sizes, rotor diameters, and pad compounds must be initially configured to provide the correct range of
vehicle bias when using a single bore / tandem outlet master cylinder. If excessive rear brake bias is experienced, an inline adjustable
proportioning valve can be used to decrease the rear line pressure to help bring the vehicle into balance. If excessive front brake bias
is experienced, first consideration should be given to increasing the rear brake bias to bring the vehicle into overall balance.

Race Pedal with Dual Master Cylinders and Balance Bar:

Master cylinders must be sized to match the calipers and allow the pedal balance bar to operate near the center of its travel. If it is not
possible to fine tune the bias within the adjustable range of the balance bar, then consideration must be given to changing a master
cylinder bore size or some other aspect of the brake system to bring the car into balance. Larger bore master cylinders will generate
less pressure while decreasing pedal travel. Smaller bores master cylinders will generate higher line pressures with an increase in
pedal travel.

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