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Benchtop Programming Solutions

Power up and reprogram OBD-II compatible ECUs outside of the vehicle

Made in the USA

EFI Connection backs manufacturing in the U.S.A.

Many of our products are created locally within the manufacturing community of Erie, PA, USA!

SBC LT1 Kits

24x and 58x Crank & Cam Signal Conversion Kits

for Small-Block Chevy, LT1/LT4, Gen VI BBC, and 4.3L V6 Engines

Welcome to EFI Connection

Our site has more Crank and Cam Signal Kits, Connectors, Terminals, and Professional Series ECU Extensions than ever before!

Giant Inventory of GM Connectors

Are you looking for that hard-to-find connector for your GM fuel injection harness? No knock-offs here. We stock Delphi, Molex, Bosch, Kostal, and Yazaki connectors to allow you to properly service your GM harness. You can  utilize the menus at the top of each page, or click here to see our connectors.

Modernize Your Early SBC, TPI, or LT1/LT4 Engine

Our EFI 24x™and EFI 58x™ Product Lines bring Gen III LS1 PCM control and Gen IV LS3 ECM control to these popular engines. In 2008, we pioneered one crank and cam signal solution for an engine to use the popular LS-series electronics. It has now grown to 5 or more engine types and over 50 conversion kit options to suit your project. Our EFI 24x and EFI 58x product lines are the best replacement to the troublesome LT1 optispark distributor and have enabled amazing potential for these engines; even 8,000 rpm capabilities.

EFI Connection is your DIY Headquarters

We offer the quality Automotive TXL Wire, terminals, and connectors you will need to assemble or modify a GM fuel injection harness for your project.

EFI Connection recommends Rennsteig Tools to give your project the professional finish it deserves. Rennsteig Tools offers a wide variety of options for your harness production or repair needs. One of our favorites, built for everyone to use is the Rennsteig MultiStrip® 10 Self-Adjusting Insulation Stripper.

Best Sellers

Professional Series OBD-II Programming Switch Assembly (BLACK)


EFI 24x Crank and Cam Signal Kit w/ CKP Sensor