The Accel DFI and FAST Dual Sync distributors offer a simple way to provide crank and cam signals to your aftermarket efi system. Though the Gen VII DFI, Thruster EFI and FAST XFI system may be operated in batch-fire mode without a cam signal, use of a Dual Sync distributor allows you operate them in full sequential mode without the use of a crank trigger. We have Dual sync distributors available for most domestic V-8 applications. For high RPM & full race SB Chevy, BB Chevy and SB Ford applications, we offer crank trigger kits which include all of the nuts, bolts, spacers & brackets required for a complete installation. Use of a Dual-sync distributor with a Gen VII or Thruster EFI ECU also requires the 77101 adapter harness. Use of a crank trigger with any ACCEL DFI system requires the 77688 universal ignition harness, use with the FAST XFI or Bigstuff3 also requires an IPU ignition harness.