2006-2007 Nextel Cup SB2

 38cc chambers. 2.180 intake 1.610 exhaust.

365-368cfm@.500      430-435cfm@.800      435-440cfm @ .900      445cfm @ 1"

 The Drag Race version of these  SB2s have 33cc chambers and a 2.200 intake with 1.590 exhaust. Using 55° seats they will flow

370- 373cfm@.500      440-443cfm@.800    443- 445cfm@.900   448- 450cfm@ 1"