ANDRA FASTLANE ANDRA FASTLANE ED23 | Page 23

techtorque Non-Adjustable and Adjustable Shocks In the old days, a loose front shock – either a worn out stocker or a special 90/10 valved shock – was used to allow the nose of the car to rise quickly. That transferred as much weight as possible to the back wheels. It was simple because there was virtually no rebound (the “10” in the 90/10 rating) and a whole bunch of bump at work (the “90” in 90/10). These shocks kept the nose up in the air; you can imagine how this messed with the race car’s aerodynamics. You can still purchase shocks with 90/10 and other valving ratios designed specifi cally for maximum weight transfer. Some of these shocks have dual stage valving on the compression side that allows the nose of the car to settle on the top end. They work well, and you don’t have fi ddle with them. On the other end of the spectrum are adjustable shocks like those manufactured by AFCO, Strange Engineering, Koni, Competition Engineering, and others. Many shocks are available as single- adjustable or double-adjustable. A single-adjustable shock lets you set rebound valving only, while a double-adjustable shock lets you set compression and rebound valving. Many shocks have external adjustment knobs on the shock body with settings from softest to fi rmest. For example, Strange Engineering single-adjustable shocks have 12 rebound settings to choose from with 1 being the softest and 12 the fi rmest. The rebound adjuster is extremely sensitive; one or two “clicks” will make a signifi cant change in tuning the chassis. Here are the starting points Strange Engineering recommends for their single- adjustable shocks: Drag Race, Front • Turn to position 2 or 3 (position 1 is full counter- clockwise) • Rotate the adjustment knob to increase weight transfer (front end travel) Drag Race, Rear • Turn to position 5 • Rotate counter-clockwise to plant the tires harder • Rotate clockwise to decrease wheel hop Street, Front & Rear • Turn to position 4 or 5 • Rotate the adjustment knob clockwise for a fi rmer ride Double-adjustable shocks are often used at the rear of the car for drag racing. Chassis builder Jerry Bickel off ers this advice for initial settings: Single-adjustable front shocks like these from Strange Engineering allow for external rebound adjustment. “A good starting point for rear shock adjustment is to set the rebound adjustment tight and the bump adjuster loose. Remember that the fi nal setting that is best for your car will be found with some thoughtful trial and error and may change with track conditions.” ADJUSTMENT TIPS So, you have the shocks on the car and you know how the adjustment settings work. Now what? Here are the basic procedures for dialling in the shocks: Front or Back First? If the car wheelstands excessively or bounces on the gear change (more likely), adjust the front shocks fi rst. If the car rattles the rear tires, wheel hops, or has way too much body separation, adjust the rear shock absorbers fi rst. Front Shock Adjustment The idea is to get a smooth transition in front end movement as the car launches right through the fi rst gear change. If the car is violent on the launch and physically jerks the front wheels of