The SPOOLOGIC SL-100-071 is a brand new, direct drop-in stock replacement turbocharger for 1991.5-1993 Dodge D250, D350, W250, and W350 trucks with the 5.9L 12-Valve Cummins — intercooled applications. Built on the Holset H1C platform — the same fixed-geometry architecture as your factory turbo — matched to factory specifications so the truck runs the way it did the day it left the dealer.

This is a true stock replacement, not a performance upgrade. It’s the right turbo for daily drivers, work trucks, and restoration builds where the goal is dependable factory performance — no tuning, no supporting mods, just a turbo that bolts on and runs the way the factory unit did before it wore out.

54/83mm Compressor Wheel

Factory-spec 8+8 splitter blade compressor wheel sized to OEM specifications and matched to the factory turbine and housing geometry for stock boost response and stock power output. The larger 54mm inducer over the SL-100-070’s 52mm reflects the factory sizing change that came with the intercooled 1991.5-1993 applications.

• Inducer: 54mm
• Exducer: 83mm
• Blade design: 8+8 splitter blade

70/60mm Turbine Wheel

Factory-spec 12-blade turbine wheel matched to the compressor and housing geometry for proper spool, factory boost response, and factory drive pressure.

• Turbine inducer: 70mm
• Turbine exducer: 60mm
• Blade count: 12

Fixed-Geometry H1C Architecture

The SL-100-071 keeps the same simple, fixed-geometry H1C architecture as the factory turbo it replaces — matched compressor and turbine sizing, no aftermarket boost creep, no surprises. Bolt it on, hook up the boost reference and oil lines, and boost behavior and drivability come back exactly like they left the factory.

What’s Included

• 1 SPOOLOGIC Stock H1C Cummins turbocharger — brand new, VSR balanced
• 1 turbo flange gasket
• 1 oil drain gasket

Features

• Direct drop-in fit for 1991.5-1993 5.9L 12-Valve Cummins trucks, intercooled
• Built on the Holset H1C platform — same as factory
• 54/83mm 8+8 splitter blade compressor wheel
• 70/60mm 12-blade turbine wheel
• Supports factory horsepower and torque — no tuning required
• Extreme duty journal bearings, 360-degree thrust bearing, step gap seal rings, VSR balanced
• No core charge — ever
• Built brand new, never remanufactured

Fits 1991.5-1993 5.9L Cummins 12-Valve

• 1991.5 – 1993 Dodge 250 / 350 5.9L Cummins 12-Valve

Turbo Applications

• Replaces factory Holset H1C (1991.5-1993 5.9L 12-Valve Cummins, intercooled)

Replaces Factory OEM Part Numbers

• 3531696

1-Year Limited Warranty

Every SPOOLOGIC turbocharger is covered by a 1-Year Limited Warranty against defects in materials and workmanship from the date of purchase. Warranty coverage requires that the unit first be shipped back to SPOOLOGIC for inspection. If SPOOLOGIC determines the failure was caused by a defect in materials or workmanship, the turbocharger will be repaired or replaced at SPOOLOGIC’s discretion. Warranty does not cover damage from foreign object debris, oil starvation, contaminated oil, extended oil change intervals, over-boosting, over-fueling, improper installation, use outside the listed fitment, cosmetic wear, or normal heat cycling marks. Warranty does not cover labor, shipping, towing, downtime, or any other costs outside the turbocharger itself.