BMR Suspension TAS010 - Manual (Page 14)

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should angle upward slightly from rear to front (front mount higher than rear mount). If they are
level or angled oppositely, lower the rear mounting point. This angle helps determine weight
transfer upon acceleration. Each vehicle, depending on front-to-rear weight distribution will
vary slightly and favor a “sweet” spot but a slightly upward angle of 1-2 degrees generally is
optimal.
3. Driveline angle. Driveline angle should not have changed however, for long u-joint life
and a quieter driveline it is important to make sure. If the angle is more than 2-3 degrees,
refer to the BMR torque arm instructions for the proper adjustment procedure.
4. Shock settings. An entire book could be written on this subject but we will just touch on
the basics. A lot of shocks have adjustments for both compression and rebound. It is
important to understand that a shocks job is to control the motion of the spring. For
optimal control, you never want the spring to collapse or extend too quickly.
Determining those settings will differ for everybody since vehicle corner weights, desired
ride quality, driving behavior, etc. play a role in finding what is optimal for that particular
individual. It is generally best to start with softer settings and work your way up. The
idea is to keep the tire firmly planted to the asphalt. Too much of either adjustment will
not only create a harsh ride but will force the tires to bounce and lose traction during
aggressive driving. The following recommendations are very basic and intended for
street driving. Begin with the compression settings at full soft and the rebound settings
two clicks from zero. Drive the car over varying road conditions and work your way up
to a setting that feels firm yet still comfortable without excessive bounce over road
irregularities. Once the rebound is set, begin adjusting the compression until ride quality
begins to suffer then back a click. These settings should provide good all-around
handling and ride quality, further adjustment may be necessary for very aggressive
driving habits such as road course and autocross racing.
5. Roll Center (Watts Link Height). Roll center (RC) works in conjunction with the
vehicles center-of-gravity (CG) height. Front RC also plays a role in determining an
optimal rear RC since too much variance between the two can result in unpredictable and
sudden body roll. Since both of these factors vary from car-to-car, finding the ideal
setting will be different for everyone. The difference between the RC and the CG height
determines the amount of weight shift (body roll) when cornering. The center hole on the
Watts Link mount is a good place to start since it relates to the exact center of the axle. If
the vehicle has been lowered excessively, it may be beneficial to begin in one of the
lower mounting holes. Find a place for testing where you can aggressively drive around
a corner consistently. Try a few settings up and down and choose the one that produces
the least amount of body roll.
6. Alignment. Once all the above settings have been decided, the vehicle should have a 4-
wheel alignment. This will insure that the rear end is square in the chassis.
If additional help is necessary with the installation or setup of this kit, please call BMR
Suspension at 813-986-9302 or email [email protected].