For applications or projects where our standard Gen V LT swap manifolds (BHS516 and BHS3116 style) don't quite fit and our "center dump" manifold (BHS5188) exits too far forward, our new "rear dump" cast iron swap manifolds have arrived. These differ in that they exit in a straight-down fashion much like a block hugger header but exit more toward the rear of the engine than our "center dump" manifolds. Cast out of the same Hi-Silicon-Moly Ductile Iron as most of our other lines, it will be tough to find a more durable, streamlined, and quiet exhaust option. Available in natural cast, silver ceramic, or black ceramic finishes, these manifolds are offered with flanges, gaskets, and flange hardware for connecting to our lineup of adapter pipe kits. This not only allows for the easy addition of catalytic converters but also makes it simple to connect to our many exhaust system options.
FEATURES:
- 2.5-inch outlet diameter offers improved flow for maximum performance from a cast iron exhaust manifold
- Tight tuck design that provides an exit between our standard swap manifolds and center dump manifolds
- Intended for GM Gen V LT engine swap applications where durability, quiet operation, and leak-free sealing is desired
- Available in Natural as-cast finish for a factory appearance, silver ceramic, or black ceramic
- Cast from Hi-Silicon-Moly Ductile Iron to provide durability and corrosion resistance
- Perfect complement to Hooker engine swap mount plates and Holley engine swap oil pans
- Hardware included: Nickel plated steel mating flanges, MLS mating flange gaskets, and mating flange hardware
- Similar to SBC driver side manifold (HKR8525) - same exit centerline but raised up 1.36-inches
EMISSIONS
This product is engineered to facilitate the installation of a later model, emissions friendly engine into a vintage / classic vehicle. Federal guidelines indicate that an engine swap is allowable if one or more of the following conditions apply:
If there is a reasonable basis for knowing that emissions are not adversely affected as described in the EPA Tampering Policy dated November 23rd, 2020
The resulting vehicle is identical (with regard to all emissions related parts, engine design parameters and engine calibrations) to a certified configuration of the same or newer model year as the vehicle chassis
The vehicle is a uncontrolled vehicle - Vehicles that were manufactured before emission control regulations took effect are called uncontrolled vehicles. Aftermarket parts regulations and anti-tampering laws do not apply to these vehicles
An EO legal engine swap kit is utilized (such as a GM EROD)
The vehicle is being used for Competition Use Only - Racing Use Only Vehicles are vehicles that are used exclusively for competition that are not registered and that may never be used on the street
Consumers are responsible for complying with laws prohibiting tampering, and for ensuring that modified vehicles are operated in a manner that complies with applicable laws.
Motor vehicle emissions standards are intended to help achieve and maintain air quality goals that benefit human health and the environment. The U.S. Environmental Protection Agency, the California Air Resources Board, Environment Canada, and other regulatory agencies prohibit the operation of vehicles on public roads that violate applicable emissions standards. The alteration of certified production vehicles to modify, remove, or render inoperable emissions control hardware or software, known as "tampering" is prohibited by the U.S. Clean Air Act and other laws. Tampering with motor vehicles emissions control systems is punishable by substantial monetary penalties.
Holley is committed to performance parts that allow enthusiasts to modify their vehicles and meet emission requirements. The information provided here is intended to provide general guidance of interest to most consumers. This guidance may not apply to all vehicles or all situations. It is up to each consumer to evaluate his or her own situation and take the steps necessary to comply with applicable laws. The websites listed below have more information about regulations and policies pertaining to motor vehicle emissions. You should also check the regulations applicable to your local area.
TECH RESOURCES
Breaking in an engine with ceramic-coated versions of these manifolds will most likely result in damage to the coating and VOID all warranties providing coverage to it. HOOKER recommends using bare cast-iron manifolds or an old set of headers to break-in engines to avoid coating damage. Ceramic-coated manifolds require several heat cycles to fully cure before they will withstand extreme heat, so care should be taken to provide a series of 4 to 5 intermittent heat cycles to "set" the coating prior to putting the vehicle into service. An incremental increase in run duration and throttle angle should be added to each successive cycle; initial and final run durations between approximately 1 and 7 minutes will be sufficient to set the coating. Certain engines with the knock sensors on the sides of the block: passenger side will need to be clocked for extra clearance. Unplug the sensor by pulling the gray clip back and pressing in the center. Use a 13mm wrench to loosen the knock sensor and turn as shown in instructions. Once complete, be sure that the wire is away from the manifold. Heat sleeve or tape is recommended at a minimum or use Hooker BHS519 heat shield for best results.
