Dropping a Gen V LT engine into your 1965–1970 B-body? Speed Engineering's 1-7/8" LT swap longtube headers are built specifically for these full-size GM platforms — mandrel bent, TIG-welded, and CNC-machined for a precise, port-matched fit on Impala, Caprice, Bel Air, and Biscayne LT swap builds. Compatible with 5.3L and 6.2L LT1 and LT4 engines. Dyno proven to deliver over 25 rear-wheel horsepower over stock manifolds.
Built from 304 natural stainless steel with standard graphite manifold gaskets included.
⚠️ Important Installation Notes:
- Gen V LT direct injection engine swaps only — these headers are NOT compatible with SBC or BBC engines
- Adjustable motor mounts with 1" offset back are required for proper fitment
- 4L80E or older Turbo 350/400 transmission — bellhousing ears may need to be trimmed for proper clearance
Features:
- Full 1-7/8" Port-Matched Primary Tubes — Full-diameter flow from cylinder head to collector for maximum exhaust scavenging
- 3" Collector — Optimized for strong low-to-mid RPM torque
- Mandrel Bent Tubing — Consistent tube diameter through every bend; no crimping, no restriction
- CNC Machined Flanges — Precision fit at the cylinder head for a leak-free seal
- 304 Natural Stainless Steel Construction — Corrosion resistant, heat tolerant, and built to last
- Longtube Header Design — Maximum scavenging efficiency vs. shorty or mid-length headers
- Standard Graphite Manifold Gaskets Included
- Dyno Proven — 25+ RWHP gain on LT applications
- Compatible with 5.3L, 6.2L, LT1, and LT4 Engines
- V8 LT Engines Only
Vehicle Applications:
Note: All applications listed are Gen V LT swap conversions. These headers are not compatible with the original factory engines in these vehicles.
Chevrolet Bel Air — B-Body (RWD)
- 1965 Chevrolet Bel Air (RWD) — LT Swap
- 1966 Chevrolet Bel Air (RWD) — LT Swap
- 1967 Chevrolet Bel Air (RWD) — LT Swap
- 1968 Chevrolet Bel Air (RWD) — LT Swap
- 1969 Chevrolet Bel Air (RWD) — LT Swap
- 1970 Chevrolet Bel Air (RWD) — LT Swap
Chevrolet Biscayne — B-Body (RWD)
- 1965 Chevrolet Biscayne (RWD) — LT Swap
- 1966 Chevrolet Biscayne (RWD) — LT Swap
- 1967 Chevrolet Biscayne (RWD) — LT Swap
- 1968 Chevrolet Biscayne (RWD) — LT Swap
- 1969 Chevrolet Biscayne (RWD) — LT Swap
- 1970 Chevrolet Biscayne (RWD) — LT Swap
Chevrolet Caprice — B-Body (RWD)
- 1966 Chevrolet Caprice (RWD) — LT Swap
- 1967 Chevrolet Caprice (RWD) — LT Swap
- 1968 Chevrolet Caprice (RWD) — LT Swap
- 1969 Chevrolet Caprice (RWD) — LT Swap
- 1970 Chevrolet Caprice (RWD) — LT Swap
Chevrolet Impala — B-Body (RWD)
- 1965 Chevrolet Impala (RWD) — LT Swap
- 1966 Chevrolet Impala (RWD) — LT Swap
- 1967 Chevrolet Impala (RWD) — LT Swap
- 1968 Chevrolet Impala (RWD) — LT Swap
- 1969 Chevrolet Impala (RWD) — LT Swap
- 1970 Chevrolet Impala (RWD) — LT Swap
Frequently Asked Questions:
Q: Will these headers work with my SBC or BBC engine? No. These headers are designed for Gen V LT direct injection engine swaps only and are not compatible with standard small block Chevy or big block Chevy engines.
Q: Do I need special motor mounts? Yes. Adjustable motor mounts with a 1" offset back are required for proper fitment with these headers.
Q: Will these fit with a 4L80E or older Turbo 350/400 transmission? These headers may require trimming of the bellhousing ears on 4L80E or older Turbo 350/400 transmissions for proper clearance.
Q: What is the difference between these headers and the LS swap B-body version? The key difference is the engine family. This listing is designed for Gen V LT direct injection engine swaps including LT1 and LT4. The LS swap B-body listing is designed for GM LS engine swaps including LS1, LS2, LS3, LS6, and LSA. Make sure you select the correct headers for your specific engine swap.
Q: What engines are these headers compatible with? These headers are compatible with GM Gen V LT V8 engines including 5.3L, 6.2L, LT1, and LT4.
Q: How much horsepower do these headers add? Speed Engineering's 1-7/8" LT swap longtube headers are dyno proven to add over 25 rear-wheel horsepower compared to stock exhaust manifolds on LT applications.
Q: What material are these headers made from? 304 natural stainless steel with full TIG-welded construction and CNC-machined flanges.
Q: Are gaskets included? Yes. Standard graphite manifold gaskets are included with the headers.
Q: Are these headers street legal? No. These are race-only headers intended for closed-course competition use only. Installation on a street-driven vehicle may violate the Clean Air Act (42 U.S.C. 7522(a)(3)).
⚠️ Race Use Only: This product is manufactured and sold for installation on vehicles used solely for competition. Once installed, the vehicle may not be used, registered, or licensed for use on a public road or highway. Installation on a street-driven vehicle may violate the Clean Air Act 203(a)(3), 42 U.S.C. 7522(a)(3).
