Package/bundle discounts may be available, contact us at sales@efisupply.com for custom system quotes


**FREE Shipping on All Terminator EFI systems**


Note: Many different Holley Terminator EFI systems and options are available, please be sure to scroll down to see all listed items and Holley HPEFI products.

Not sure which aftermarket EFI system is best for you? Click here to view our aftermarket EFI buyer's guide.

Looking for a summarized feature listing? Click here to view a list of features of our aftermarket efi systems



  • 4-barrel carburetor to fuel injection conversion kits for 250-600 HP V8 engines
  • No laptop required
  • Fits any square (Holley 4150™) flanged intake
  • Self-tunes while you drive
  • 950 CFM Throttle Body with CFD computer designed venturi taken from Holley’s NASCAR® throttle body
  • 80 lb/hr injectors (@ 43 PSI)
  • Connections for Ford, GM TH350 and 700R4, and other transmission linkages
  • Provides ignition timing control on engines with GM Computer-Controlled Small Cap HEI and Ford TFI distributors (requires adapter)
  • Self-tunes to deliver the perfect air/fuel mixture in real time for optimized fuel economy and power
  • Virtually maintenance free - keeps your vehicle reliable and ready to drive
  • Patent pending annular discharge fuel ring for maximum flow and optimum fuel atomization - No restrictions or delay in fuel flow like booster designs
  • Trouble-free performance with today’s fuels –eliminate vapor lock and fuel varnish problems
  • Serviceable sensors integrated into throttle body and pre-wired for a simple one-click connection - don’t get stranded by competitive designs
  • ECU fully potted and sealed for protection from vibration, dust and moisture
  • Terminator ECU can be EASILY updated to Holley “HP” ECU specs with a free online software download.
  • ECU can then be used for LSX, boosted, nitrous, and many other applications in the future as you desire!
  • Trouble-free performance with today’s fuels - put an end to vapor lock and fuel varnish problems!


All EFI systems purchased from efisupply.com include a ECU calibration matched to your application. We have a large library of naturally aspirated and power adder calibrations and are likely to have the file you need. If we don't already have it, we'll work with you to develop a new calibration for your combination.


Holley Terminator EFI Systems (click description to see kit contents)
P/N 550-405, Terminator EFI - w/ raw cast TBI
P/N 550-405K, Terminator EFI - w/ raw cast TBI & fuel system
P/N 550-406, Terminator EFI - w/ hardcore gray TBI
P/N 550-406K, Terminator EFI - w/ hardcore gray TBI & fuel system
We work hard to provide competitive pricing on our entire offering of aftermarket electronic fuel injection systems and components, if you find anything we sell somewhere else for less contact our sales staff at sales@efisupply.com and we'll do out best to match or beat their price!


Click here to download a Holley EFI Product Catalog