Swapping a GM LS engine into your Fox Body or SN95 Mustang and want everything you need to do it right? This combo kit pairs Speed Engineering's 1-7/8" LS swap longtube headers with a complete AJE K-member package — giving you the headers, K-member, motor mounts, spring perches, and steering shaft all in one purchase. Dyno proven to deliver over 25 rear-wheel horsepower over stock manifolds.
Built from 304 natural stainless steel with merge spikes and standard graphite manifold gaskets included.
⚠️ Important Installation Notes:
- GM LS engine swaps only — these headers are NOT designed for Ford engines of any kind
- Headers have only been tested successfully with AJE Motor Mounts, Flaming River Steering Shafts, and AJE K-Members — compatibility with other combinations is unknown and not guaranteed
Speed Engineering Headers — Kit Includes:
- 1-7/8" Longtube Headers with Merge Spikes
- Standard Graphite Manifold Gaskets
AJE Suspension — Kit Includes:
- 1979–2004 AJE K-Member
- LS Engine Motor Mounts
- 1979–2004 Spring Perches — Allows use of factory A-arms and springs
- 1979–2004 Manual or Power Steering Shaft Kit
Header Features:
- Full 1-7/8" Primary Tubes with Merge Spikes — Full-diameter flow from cylinder head to collector for maximum exhaust scavenging
- 3" Collector with Merge Spikes — Optimized merge geometry 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 LS applications
- Compatible with 4.8L, 5.3L, 6.0L, 6.2L, LS1, LS2, LS3, LS6, and LSA Engines
- V8 LS Engines Only
Vehicle Applications:
Note: All applications listed are GM LS engine swap conversions. These headers are not compatible with Ford engines of any kind.
Ford Mustang — Fox Body (RWD)
- 1979 Ford Mustang (RWD) — LS Swap
- 1980 Ford Mustang (RWD) — LS Swap
- 1981 Ford Mustang (RWD) — LS Swap
- 1982 Ford Mustang (RWD) — LS Swap
- 1983 Ford Mustang (RWD) — LS Swap
- 1984 Ford Mustang (RWD) — LS Swap
- 1985 Ford Mustang (RWD) — LS Swap
- 1986 Ford Mustang (RWD) — LS Swap
- 1987 Ford Mustang (RWD) — LS Swap
- 1988 Ford Mustang (RWD) — LS Swap
- 1989 Ford Mustang (RWD) — LS Swap
- 1990 Ford Mustang (RWD) — LS Swap
- 1991 Ford Mustang (RWD) — LS Swap
- 1992 Ford Mustang (RWD) — LS Swap
- 1993 Ford Mustang (RWD) — LS Swap
Ford Mustang — SN95 (RWD)
- 1994 Ford Mustang (RWD) — LS Swap
- 1995 Ford Mustang (RWD) — LS Swap
- 1996 Ford Mustang (RWD) — LS Swap
- 1997 Ford Mustang (RWD) — LS Swap
- 1998 Ford Mustang (RWD) — LS Swap
- 1999 Ford Mustang (RWD) — LS Swap
- 2000 Ford Mustang (RWD) — LS Swap
- 2001 Ford Mustang (RWD) — LS Swap
- 2002 Ford Mustang (RWD) — LS Swap
- 2003 Ford Mustang (RWD) — LS Swap
- 2004 Ford Mustang (RWD) — LS Swap
Frequently Asked Questions:
Q: What is included in this kit? This kit includes Speed Engineering 1-7/8" LS swap longtube headers with merge spikes and graphite manifold gaskets, plus the AJE K-member, LS engine motor mounts, 1979–2004 spring perches, and a manual or power steering shaft kit.
Q: Will these headers work with my Ford engine? No. These headers are designed for GM LS engine swaps only and are not compatible with Ford engines of any kind.
Q: What motor mounts and K-member are compatible with these headers? These headers have only been tested successfully with AJE Motor Mounts, Flaming River Steering Shafts, and AJE K-Members — all of which are included in this kit. Compatibility with other combinations is unknown and not guaranteed.
Q: Will the AJE spring perches allow me to keep my factory A-arms and springs? Yes. The included 1979–2004 spring perches are designed to allow the use of factory A-arms and springs.
Q: What is the difference between this listing and the headers-only version? This listing is a complete combo kit that includes the AJE K-member, motor mounts, spring perches, and steering shaft kit in addition to the Speed Engineering headers. The headers-only listing includes just the headers and gaskets.
Q: What LS engines are these headers compatible with? These headers are compatible with GM LS V8 engines including 4.8L, 5.3L, 6.0L, 6.2L, LS1, LS2, LS3, LS6, and LSA.
Q: How much horsepower do these headers add? Speed Engineering's 1-7/8" LS swap longtube headers are dyno proven to add over 25 rear-wheel horsepower compared to stock exhaust manifolds on LS applications.
Q: What material are these headers made from? 304 natural stainless steel with full TIG-welded construction, CNC-machined flanges, and merge spikes.
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).