The Ultimate Roush 347 IR Crate Engine for Ford Performance Builds
The Roush SF347IRGTC 347 IR crate engine delivers race-proven, high-performance power in a fuel-injected package ready to transform your classic Mustang, hot rod, or custom build. As part of our extensive Ford Windsor collection, this 347 cubic inch stroker V8 produces an impressive 465 horsepower and 425 lb-ft of torque —making it one of the most formidable naturally aspirated small-block Ford crate engines in Roush’s lineup.
Based on a new four-bolt main iron block with a forged steel crank, forged connecting rods, and forged aluminum pistons, this engine combines Roush’s championship-winning engineering with modern individual-runner fuel injection (IR EFI) to deliver exceptional throttle response and breathtaking high-rpm performance . Whether you’re building a weekend warrior, a track-day monster, or a show-winning restomod, this Roush 347 IR crate engine provides the foundation for an unforgettable driving experience.
What Makes the Roush 347 IR the Ultimate Small Block Ford Crate Engine?
The Roush 347 IR is far more than a standard 302 Windsor—it’s a carefully engineered stroker that pushes the boundaries of pump-gas performance. Based on a new four-bolt iron block with a 4.030-inch bore and 3.400-inch stroke, this 347 cubic-inch small-block Ford features a forged bottom end for exceptional durability under high-performance driving conditions . The Individual Runner (IR) EFI system sets this engine apart, featuring an eight-stack intake that delivers crisp throttle response and a stunning visual appearance under the hood . Roush’s reputation for quality is backed by a comprehensive 2-year/24,000-mile limited warranty .
Roush 347 IR Horsepower and Torque Figures
This 347 stroker crate engine produces impressive output that puts most performance engines to shame:
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465 horsepower — dyno tested and verified
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425 lb-ft torque — strong, broad power band
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Forged rotating assembly — steel crank, forged rods, forged pistons
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CNC-ported aluminum cylinder heads for exceptional flow
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Individual Runner EFI with 8-stack intake
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Hydraulic roller cam — low maintenance, excellent durability
Complete Roush 347 IR Engine Specifications
Engine Block and Rotating Assembly
The foundation of this Roush 347 stroker is a new Ford 4-bolt main iron block featuring:
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4-bolt main caps — exceptional bottom-end strength
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4.030-inch bore — machined to exacting tolerances
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3.400-inch stroke — delivers 347 cubic inches of displacement
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Forged steel crankshaft — built to handle serious horsepower
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Forged steel connecting rods — race-proven durability
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Forged aluminum pistons — lightweight and strong
Roush Aluminum Cylinder Heads
The Roush CNC-ported aluminum cylinder heads provide exceptional flow:
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CNC-ported intake runners — precise airflow optimization
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2.02-inch intake valves — swirl polished
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1.60-inch exhaust valves — swirl polished
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Aluminum construction — lightweight and efficient
Hydraulic Roller Camshaft and Valvetrain
The performance hydraulic roller camshaft delivers aggressive yet streetable power:
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Hydraulic roller cam — low maintenance, long-term durability
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High-lift profile — optimized for 347 cubic inches
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1.6:1 roller rocker arms — precise valve actuation
Individual Runner EFI System
The Roush Individual Runner (IR) EFI system is a standout feature:
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Eight-stack intake manifold — stunning visual appearance
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Individual runner design — exceptional throttle response
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Fuel injection — precise fuel delivery for optimal performance
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Includes all sensors — plug-and-play compatibility
What’s Included with Your Roush 347 IR Crate Engine
When you purchase this Roush SF347IRGTC from NH Race Engine, you receive a complete turn-key engine assembly:
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✅ Fully assembled long block with forged internals
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✅ Individual Runner EFI system with 8-stack intake
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✅ Aluminum cylinder heads with CNC-ported runners
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✅ Harmonic balancer
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✅ Oil pan
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✅ Valve covers
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✅ Timing cover
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✅ Spark plugs and wires
Important Note: Ancillary components such as the ECU, wiring harness, and front-end accessory drive components may need to be obtained separately depending on your specific application. The engine is currently listed as “Not Available At This Time” at Summit Racing .
Roush 347 SR vs 347 IR — Understanding Your Options
Roush offers two primary 347 crate engine variants:
| Feature | 347 IR | 347 SR |
|---|---|---|
| Horsepower | 465 HP | 410 HP |
| Torque | 425 lb-ft | 400 lb-ft |
| Fuel System | Individual Runner EFI | Standard EFI |
| Intake | 8-stack IR | Standard manifold |
| Forged Internals | Yes | Yes |
| Warranty | 2-year/24,000-mile | 2-year/24,000-mile |
The 347 IR featured here represents the premium option, with the stunning individual runner EFI system and higher output figures . The additional power and visual appeal of the IR system make it the choice for show-quality builds and serious performance enthusiasts.
347 Stroker Engine Swap — Compatibility and Considerations
The Roush 347 IR is a drop-in replacement for any vehicle originally equipped with a small-block Ford Windsor. The compact 347 cubic-inch package is ideal for:
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1965-1970 Mustang restomods
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1967-1968 Mustang custom builds (ECD Auto Design uses Roush 347 engines in their builds)
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Fox-body Mustang (1979-1993)
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Street rods and custom builds
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Classic Ford cars requiring modern performance
Installation Notes
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Designed for pre-1976 street vehicles or off-road applications
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Premium fuel recommended for optimal performance
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Professional tuning required for ECU calibration
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Manual or automatic transmission compatible
Why Choose NH Race Engine for Your Roush Crate Engine?
As a Netherlands-based specialist serving performance enthusiasts across Europe, NH Race Engine brings unmatched expertise to your Ford project. We understand the unique requirements of European builds—from shipping logistics to regional considerations. Our team can guide you through compatibility, ECU tuning, and installation considerations for your specific build.
Browse our Ford Windsor collection and other crate engine offerings to find the perfect solution for your build.
Roush 347 IR Engine FAQs
What is the horsepower and torque of the Roush 347 IR?
The Roush 347 IR produces 465 horsepower and 425 lb-ft of torque .
What makes the 347 IR different from the 347 SR?
The 347 IR features an Individual Runner (IR) EFI system with an eight-stack intake manifold, producing 55 more horsepower (465 vs 410) than the standard 347 SR .
What is the warranty on Roush crate engines?
Roush Performance backs their crate engines with a 2-year/24,000-mile limited warranty .
Is the Roush 347 IR available?
Current availability is limited. Summit Racing indicates the SF347IRGTC is “Not Available At This Time” . Contact NH Race Engine for current availability and ordering options.
What vehicles can the Roush 347 IR be installed in?
The 347 IR is a drop-in replacement for any vehicle originally equipped with a small-block Ford Windsor, including classic Mustangs, street rods, and custom builds .
What fuel does the Roush 347 IR require?
Premium fuel is recommended for optimal performance and drivability.

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