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FlowTech Exhaust Manifold 31730-3FLT

FlowTech Exhaust Manifold 31730-3FLT
FlowTech Exhaust Manifold 31730-3FLTFlowTech Exhaust Manifold 31730-3FLTFlowTech Exhaust Manifold 31730-3FLTFlowTech Exhaust Manifold 31730-3FLTFlowTech Exhaust Manifold 31730-3FLTFlowTech Exhaust Manifold 31730-3FLTFlowTech Exhaust Manifold 31730-3FLTFlowTech Exhaust Manifold 31730-3FLTFlowTech Exhaust Manifold 31730-3FLT
$518.99 ea
NEWARRIVING SOONEstimated Ship Date 10/16/2023 (If Ordered Today)21 available from HOLLEY PERFORMANCE PRODUCTS as of 09/23/2023
Model: 4006352
Supplier has not provided any fitment data for this product.
These Flowtech cast iron exhaust manifolds have a 2.25 inch outlet, natural cast finish and are designed to hug close to the engine block so they fit into a wide variety of replacement and engine-swap applications at a budget friendly price. Being cast iron means they will provide years of leak-free performance with less under hood noise than traditional headers. Plus, their shorty design means you can route exhaust tubing close to your frame/floor pan for maximum ground clearance.
  • Intended For GM LS Engine Swap
  • 304 Stainless Steel Mating Flanges Included
  • 2 Bolt Exit Flange Configuration
  • Hi-Silicon-Moly Ductile Iron To Provide Durability
  • Tight Tuck Design
Holley Performance Emission Code 4: This part is legal for sale or use on Racing Use Only Vehicles. The following vehicles are considered Racing Use Only Vehicles: 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. WARNING: It is against the law to install this part on an Emissions Controlled Vehicle
About FlowTech

Flowtech Performance Exhaust was founded in 1994, by exhaust market expert Gary Biggs, with the mission of delivering high quality performance exhaust at a great value. The mission was successful and in less than two decades Flowtech became the leader in value priced exhaust systems.

Flowtech cornered its place in the market with aggressive and memorable product names such as Raptor™, Terminator™, Afterburner™ and Warlock™. Flowtech even revived some names from back in the day like Purple Hornies™.

Flowtech made its mark with simple yet effective improvements like slotted port flanges giving added wiggle room during header installation. They dimpled their tubes at the port to make more room for the header bolts and they parallel ground their flanges to assure a tight seal. Flowtech innovations include their unique Afterburner headers which separated the odd firing cylinders with a velocity tube to improve scavenging. Their patented Warlock bypass muffler won the SEMA best new product award for its revolutionary open or closed design in 1996.

When Flowtech became part of Holley Performance Products in 1999, the company continued to focus on value, with an emphasis on late model cars and trucks. Headers and exhaust systems were developed for Mustangs, Camaros, and all types of full size trucks - including diesels. The same innovation continues today with the addition of universal X-pipe kits and X-pipe kits with built in cut-outs. Continuous product updates and improvements to manufacturing processes will keep Flowtech the leader in value priced exhaust systems. We hope you enjoy your Flowtech product as much as we enjoy building it!


Download Name File Size


Application Multi-fit
Choose Your Part Manifold
Collector Diameter 2.25 inch
Emission Code 8
Engine GM Small Block Gen III/IV (LS Based)
Finish Black Ceramic
Header Finish Black Ceramic
Header Style Manifold
Material Cast Iron
Part Type Exhaust Manifold
Primary Tube Dia. 1-3/4 inch
Subframe Stock
Tube Material Cast Iron
Type of Component Manifold
WARNING CA Proposition 65 WARNING: Cancer and Reproductive Harm


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FlowTech Exhaust Manifold 31730-3FLT:
Mustang Depot 2023