keep burning up clutch discs after only a few runs. What could be the problem?
Assuming you are using the proper clutch combination for the vehicle, here are a few things to check:

1. Throw-out bearing clearance. This is absolutely critical, especially on centrifugal assisted clutches such as the Hays Street/Strip Borg and Beck. The throwout bearing should be 1/4" off of the fingers when released. The fingers open as engine rpm increases. Without the proper clearance the fingers may release the bearing and remove pressure from the plate.

2. Clutch linkage flex. If the clutch linkage is flexing, the car will usually "creep". To check, stage the car with the line lock disengaged (if so equipped). Rev the motor to launch rpm, depress the clutch, put it into gear, and see if the vehicle moves. If it does, you'll need to strengthen the linkage. If a line lock is engaged before this situation is corrected, you may burn up the clutch disc.

3. Weak motor mounts. This may allow the engine to "torque over" too far and move the clutch linkage enough to partially disengage the clutch.

4. Bellcrank, Z-bar, or firewall flex. Similar to clutch linkage flex, this situation must be corrected by whatever means necessary to prevent flex and partial clutch engagement.

5. Too "high" of a gear ratio in the differential. "High" (numerically lower) gear ratios don't provide enough torque multiplication to get heavy vehicles moving off the line fast enough, causing the driver to ride the clutch to keep the engine in its powerband. Steeper gears will solve this problem