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FlowTech Upright Headers 11587FLT

FlowTech Upright Headers 11587FLT
FlowTech Upright Headers 11587FLTFlowTech Upright Headers 11587FLTFlowTech Upright Headers 11587FLTFlowTech Upright Headers 11587FLTFlowTech Upright Headers 11587FLTFlowTech Upright Headers 11587FLTFlowTech Upright Headers 11587FLTFlowTech Upright Headers 11587FLT
$292.99 ea
NEWARRIVING SOONEstimated Ship Date 10/16/2023 (If Ordered Today)74 available from HOLLEY PERFORMANCE PRODUCTS as of 09/23/2023
Model: 4006355
Supplier has not provided any fitment data for this product.
These Flowtech upright derby style headers fit the 2.8L, 3.1L and 3.4L GM V6 engines with both round port or D-port style exhaust ports. 1-1/2 in. and 1-5/8 in. mandrel bent primary tubes provide consistent tubing diameters for smooth flow of the exhaust pulses and increase the cylinder scavenging of the exhaust to improve engine breathing. The headers are constructed from heavy duty 16-gauge 409 stainless steel tubing for increased strength and durability. These headers use a 10 in. long, 2.5 in. collector with 20 in. long primary tubes. The 3/8 in. thick header flange provides a leak-free seal and maximizes strength.
  • Better Exhaust Pulse Flow And Improved Performance
  • Increased Exhaust Flow And Improved Throttle Response
  • Heavy Duty 16-Gauge 409 Stainless Steel For Strength/Durability
  • 3/8 in. Thick Header Flange For A Leakfree Seal
  • Header Gaskets Included
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!


Application Race Car
California Proposition 65 Chemical Name Chromium (hexavalent compounds)
California Proposition 65 Required Yes
CARB (California) Compliant No
Collector Diameter 2.50 inch
Collector Length 10 inch
Collector Tube Size 2.500 in.
Emission Code 4
Engine Chevrolet V6
Flange Length 0.375 in.
Flange Thickness 3/8 Inch
Header Finish Natural
Header Style Upright
Inlet Port Shape D-Port
Installed Height 27 inch
Part Type Exhaust Header
Port Shape D-Port
Primary Tube Dia. 1-1/2 inch
Primary Tube Length 20 inch
Tube Diameter 1.500 in.
Tube Material 409 Stainless Steel
WARNING CA Proposition 65 WARNING: Cancer and Reproductive Harm


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FlowTech Upright Headers 11587FLT:
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