FAST · New

FAST Wiring Harness FAST Main LT1

Name: FAST Wiring Harness FAST Main LT1
Brand: FAST
SKU: fst301101
Price: 453.95 USD

MPN 301101 · Store SKU fst301101

$453.95

CHECK AVAILABILITY0 in supplier warehouses. Ask JuiceBuilt about availability.

Supplier stock checked 11/8/2026, 5:05:40 AM UTC. Adding a part does not reserve it.

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Request a return within 30 calendar days after delivery. New parts must be unopened and unused.

Shipping & returns ↗This policy does not limit rights required by law.

Free standard shipping on eligible parts orders of $100 or more. Oversized and freight items excluded. Fitment, taxes, availability and final totals are confirmed before payment.

Product details

FAST offers several main harness options to aC-Commodate most customers' needs. The XFI Main Harness is responsible for connecting your XFI ECU to sensors as well as digital dashes, EGT modules, and various optional accessories. The Main Harness also handles communication between the ECU and ignition devices. Main harnesses are available in TPI, LT-1, LS-1 through 9 (including truck/suv designs), Modern Hemi, Carburetor Conversions and even Rear-Engine Dragsters and Boats. FAST also offers Main Harnesses that come terminated on the sensor side but non-terminated on the ECU side to allow for a truely custom fit. All terminals, seals and connectors are available individually, so don't hesitate to try your hand at crafting your own custom harness from start to finish. XFI Main Harness 301101 is great for conversions from carburetor to fuel injection or existing LT-1 based projects. Terminals are generally LT-1 based. XFI Harness for GM LT1 Sensors.

Manufacturer fitment & guides

Check 301101 against the manufacturer’s application information below.

Part-specific notes

Not CARB approved. Destination and intended-use restrictions must be checked before sale.
California Proposition 65: Y

Manufacturer documents

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