Difference between Holley Terminator LS and Terminator X LS?

[Paraman1]

I am trying to figure out what the difference between the Holley EFI Terminator X part number 550-903 and the Holley Terminator LS MPFI kit part number 550-608 are?

[Tinker]

The 550-903 uses the terminator ecu or xmax ecu that will also control single wire DBW throttle and electronic transmission control.
The 550 608 appears to use a hp ecu.
Double check what ecu is included with the kit you choose.