EFI 24x™ LT1/LT4. Since 2008, our 24x LT1 conversions have been eliminating the optispark distributor and transforming LT1 engines. EFI Connection's 24x LT1 systems are designed to output the 24x crank and 1x cam signal of a GM Gen III LS-Series engine. This means that LS1 compatible ECUs can now be used on 24x equipped LT1 engines!

Modernize Your Early SBC, VI Gen BBC, TPI, 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.

Take control of your GM Gen V LT4, LT1, L83, or L86 engine with Terminator X! Do not settle for a factory ECU with a cumbersome tuning interface when you can have complete control of your engine, self-learning fuel strategies and the proven, race-winning technology of Holley EFI at a budget-friendly price!

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The Holley EFI Terminator X Max GM Gen V LT4 Direct Injection Kit with 6L80E/6L90E Transmission Control provides Advanced Engine Control System. This system is designed for early application LT4 engines, making it essential for both performance and tuning flexibility.

Howell EFI Adds to Lineup of Gen 4 LS and LSA Swap Harnesses (2008-2014) Engines

Test boost against time, gear, RPM, and speed in your late Gen V LT4 engine via the Holley Terminator X Max EFI kit (550-1624). This kit is the perfect way to enjoy GM 4L60 and 4L80 transmission control within 1988-1998 Chevy and GMC C/Ks.

100's of LT1/LT4 Engines are running with the Torqhead Gen 3 PCM and Ignition Conversion. Get your conversion today! TorqHead LTD products are for off-road use only.

The Edelbrock Performer RPM Air-Gap LT1/LT4 intake manifolds feature a tunnel-ram design that offers performance increases in the 1500-6500 rpm range. The air-gap design separates the runners from the hot engine oil, resulting in a cooler, denser charge for more power.

Whether you are updating your LT1/LT4 electronic fuel injection system to use a newer ECU or update the ignition system on your carbureted LT1 engine, an EFI 58x LT1/LT4 conversion will equip your LT1/LT4 engine with the crank and cam signal components necessary to be controlled by popular GM and aftermarket LS-Series compatible ECUs.