You don't have to have a fast car to be banned. In 1975, my Z/SA 65 Valiant with a 170 slant six, could run 1/2 sec under the index. The following year NHRA made a rule change, for Y/S and Z/S, stating "for 4 cyl engines only". They did not change the weight breaks. That meant I would have to race in X/SA, 2 classes higher, at the same weight and horse power as before. Effectivly banning my combo.
