The SPOOLOGIC Ductile Iron Exhaust Manifold Kit (SL-500-001) is a direct OE-style replacement for the factory 7.3L Powerstroke exhaust manifolds. Cast from ductile iron to resist the cracks and warping that kill stock gray-iron castings, and engineered to reseal cleanly against the up-pipes and turbo pedestal so you get your drive pressure back.

Why It Matters

The factory 7.3L cast manifolds are famous for cracking around the runners and warping at the turbo flange after years of thermal cycling. Once they crack, you lose drive pressure, spool suffers, and EGTs climb. This SPOOLOGIC ductile iron replacement pattern-matches the OE flow path but uses stronger material and cleaner castings so you get back to full spool response and stop chasing exhaust leaks under the up-pipes.

Performance Gains Over the OE Manifold

• Ductile iron resists the runner cracks that plague OE gray-iron castings
• Restores factory drive pressure and TP38/GTP38 spool response after a cracked-manifold repair
• Sealed flange machining eliminates the up-pipe exhaust leaks that kill turbo response
• Reuses factory studs, bolts, and gaskets — direct OE-style bolt-on
• Rated for stock and mild-tune EGT loads without warping

Interchange Part Numbers

F6TZ9431A, F6TZ-9431-A, F6TZ9430A, F6TZ-9430-A, F4TZ9430B, F4TZ-9430-B, F4TZ9448A, F4TZ-9448-A, F4TZ9S425A, F4TZ-9S425-A

What’s Included

• Driver-side ductile iron exhaust manifold
• Passenger-side ductile iron exhaust manifold
• Manifold gaskets
• SL-320-003 manifold bolt kit (16 bolts + 16 washers) for manifold-to-head
• Manifold-to-up-pipe hardware: 4 bolts + 4 nuts (2 per side)

Fresh Hardware Included

Factory 7.3L manifold bolts are almost always seized, snapped, or stretched by the time you pull the old manifolds. This kit ships with the SL-320-003 manifold-to-head bolt kit (16 bolts + 16 washers) plus 4 bolts and 4 nuts (2 per side) for the manifold-to-up-pipe connection — so you can bolt everything back down with fresh hardware instead of chasing broken studs.

Features

• Ductile iron casting resists cracking and warping vs. OE gray iron
• OE-pattern flange machining seals cleanly to up-pipes and turbo pedestal
• Direct bolt-on — no port matching or head machining required
• Fits TP38, GTP38, and GTP38R turbo configurations

Coating Options

Choose Raw or Ceramic Coated at checkout. Ceramic coating is a high-temp thermal barrier applied to the manifold’s exterior — it keeps exhaust heat inside the manifold where it belongs and off the engine bay.

• Raw: Bare ductile iron finish. Cost-effective, easy to inspect for cracks, ready to install as-is. Will develop surface rust and heat discoloration over time — cosmetic only.
• Ceramic Coated: High-temp ceramic thermal barrier coating. Keeps exhaust energy in the manifold for faster turbo spool, drops engine bay temperatures for cooler intake air and longer component life, resists oxidation and surface rust, and wipes clean instead of staining. Recommended for daily-driven trucks, towing, and any build where engine bay heat management matters.

Install Notes

• Manifold-to-head bolts: torque to 45 ft-lbs in the recommended sequence — over-torque cracks the flanges
• Manifold-to-up-pipe bolts: torque to 21 ft-lbs
• Turbocharger pedestal-to-manifold bolts: torque to 18 ft-lbs
• Anti-seize all fasteners — 7.3L manifold bolts routinely seize into the head; use fresh SL-320-003 hardware
• Replace up-pipe donut gaskets and pedestal O-rings while you have access
• Inspect up-pipes for collapse and cracks before reinstall
• Torque sequence: work from center outward on each head, alternating sides, in two passes

Fits 1994-2003 7.3L Powerstroke

• 1994 – 2003 Ford F-250 / F-350 / F-450 / F-550 Super Duty 7.3L Powerstroke
• 1995 – 2003 Ford E-350 / E-450 / E-550 Econoline 7.3L Powerstroke
• 2000 – 2003 Ford Excursion 7.3L Powerstroke

1-Year Limited Warranty

Every SPOOLOGIC exhaust manifold is covered by a 1-Year Limited Warranty against defects in materials and workmanship from the date of purchase. Warranty coverage requires that the exhaust manifold first be shipped back to SPOOLOGIC for inspection. If SPOOLOGIC determines the failure was caused by a defect in materials or workmanship, the exhaust manifold will be replaced at SPOOLOGIC’s discretion. Warranty does not cover damage from over-torqued or improperly torqued hardware, cracked flanges from improper install sequence, use outside the listed fitment, EGTs beyond the manifold’s rated operating range, tuning or fueling that exceeds safe exhaust gas temperatures, cosmetic wear, ceramic coating discoloration or chipping, surface rust on raw manifolds, or normal heat cycling marks. Warranty does not cover labor, shipping, towing, downtime, gaskets, hardware, or any other costs outside the exhaust manifold itself.