Building a fully custom LS swap exhaust and want the most complete stainless weld-in kit available? Speed Engineering's 3" Deluxe Edition exhaust builder kit steps it up over the standard and Fabricator Edition kits — adding both a 3" X-pipe and a 2.5" H-pipe to the weld-in mandrel bent 3" stainless tubing assortment, along with stainless band clamps. The most comprehensive builder kit in the Speed Engineering lineup for custom exhaust fabrication on LS swap builds.
Note: This is a universal weld-in build-your-own kit and is not designed for use with any specific Speed Engineering header or pipe product. Welding required.
⚠️ Important: The X-pipe section will not be a direct match-up with the included tubing and will require additional fabrication for proper installation.
Features:
- 3" Mandrel Bent Tubing — Consistent diameter throughout for maximum exhaust flow
- Weld-In Construction — Designed for permanent welded installation
- 3" X-Pipe Included — For crossover between exhaust banks on true dual builds
- 2.5" H-Pipe Included — Alternative crossover option for H-pipe style exhaust layouts
- Stainless Steel Band Clamps Included
- 304 Natural Stainless Steel Construction — Corrosion resistant and built to last
- Universal Fit — For custom LS swap exhaust fabrication
FAQ
What is the difference between this kit, the standard 3" builder kit (25-1033), and the Fabricator Edition (25-1151)?
The standard kit (25-1033) uses slip-fit construction with band clamps and includes an X-pipe. The Fabricator Edition (25-1151) uses weld-in construction with flared ends and no clamps. The Deluxe Edition (25-1112) uses weld-in construction and includes both a 3" X-pipe and a 2.5" H-pipe along with stainless band clamps — the most comprehensive option for builders who want both crossover pipe styles.
Will the X-pipe connect directly to the included tubing?
No. The X-pipe section will not be a direct match-up with the included tubing and will require additional fabrication for proper installation.
Does this kit require welding?
Yes. This is a weld-in kit and requires welding for installation.
What size tubing is included?
All primary tubing is 3" diameter, mandrel bent for consistent flow throughout. The H-pipe is 2.5".
Is this kit designed for a specific vehicle or header?
No. This is a universal build-your-own kit and is not designed for use with any specific Speed Engineering header or pipe product. It is intended for custom exhaust fabrication on LS swap builds.
What material is this kit made from?
304 natural stainless steel with mandrel-bent tubing and TIG-welded construction. Stainless band clamps are included.
Is this kit street legal?
No. This is a race-only product 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).