Same as B-31 except utilizing 1.7 R.R. N2O or S/C 8-15 lb 302 c.i.d. Best performer for 1.7 R.R., stock pistons and 6200 rpm. Great with TFS or Edelbrock heads. Minimum 30lb injectors and 80mm mass air. Recommend 3.55 or 3.73 gears. Good drivability down to 1900 rpm, mild idle, rpm range 2400-6200, works best with 89-93 EEC, needs 2600-3000 converter. Great N.A. cam for 94-95 Mustang with great drivability. With bolt-down R.R., needs 0.040" longer push rods.