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Flowmaster 817158 American Thunder Crossmember-Back Dual Exhaust System

(1969-1974 Chevrolet Nova; 1968 Chevrolet Chevy II; 1971-1974 Pontiac Ventura; 1973-1974 Oldsmobile Omega; 1973-1974 Buick Apollo)

Part of: Flowmaster American Thunder Crossmember-Back Dual Exhaust System

Other options in this family: Flowmaster 817654 Flowmaster 17201 Flowmaster 817200 Flowmaster 817174 Flowmaster 17282

Manufacturer

Picture for manufacturer Flowmaster

Part Number

817158
11 reviews
Sale Price

$949.95

1 left at this price

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Usually delivered within 2 days

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Live-in-stock inventory

Fitment guaranteed

Fitment guaranteed

Product Details

The Flowmaster 817158 American Thunder Crossmember-Back Exhaust System delivers aggressive performance sound and increased horsepower through true dual exhaust design. This complete cat-back system features mandrel-bent 16-gauge stainless steel tubing for maximum exhaust flow and durability.

Key Features:

  • True dual 2.50-inch diameter exhaust system from crossmember to rear
  • Super 44 Series performance mufflers produce deep, powerful exhaust note
  • H-pipe crossover design balances exhaust pulses for maximum power gains
  • Mandrel-bent 16-gauge stainless steel construction resists corrosion
  • Aggressive to moderate exterior sound level
  • Complete kit includes all necessary hangers and mounting hardware
  • Backed by Flowmaster's Lifetime Limited Warranty

Important Note: This system does not include header reducer cones or downpipes for factory exhaust manifolds. This is a crossmember-back system designed to connect to existing headers or factory manifolds with appropriate adapters.

Flowmaster's American Thunder series combines race-proven performance technology with street-friendly installation, making it an ideal choice for enthusiasts seeking improved sound and power without sacrificing reliability.

Products specifications

Fits

1969-1974 Chevrolet Nova; 1968 Chevrolet Chevy II; 1971-1974 Pontiac Ventura; 1973-1974 Oldsmobile Omega; 1973-1974 Buick Apollo

Inlet Inside Diameter

2.500 in.

Outlet Outside Diameter

2.500 in.

Prop 65

WARNING: Cancer and Reproductive Harm - www.P65Warnings.ca.gov

California Proposition 65 Chemical Name 2

Chromium (hexavalent compounds)

California Proposition 65 Chemical Name 1

Nickel (metallic)

California Proposition 65 Chemical Name

Chromium (hexavalent compounds)

California Proposition 65 Chemical Name

Nickel (Metallic)

System Type

Header Back

Heat Shield Attached

No

Material

Stainless Steel

Tubing Diameter

2.500 in.

Outlet Diameter

2.500 in.

Muffler Count

2

Exit Position

Dual Rear

Tail Pipe Diameter

2.500 in.

Exhaust Type

Dual

Single or Dual

Single

Title

Flowmaster 817158 Header-back System 409S -Dual Rear Exit - American Thunder - Moderate/Aggressive

Brand

Flowmaster

Catalytic Converter Quantity

0

Category

Exhaust

Clamping Type

Flat Band

Clamps Included

Yes

Drive

2WD

Emission Code

5

Exhaust Series

American Thunder

Exhaust Tip Connection

Clamp-On

Exhaust Tip Quantity

0

Exhaust Tip Quantity

Sold Separately

Exhaust Tip Shape

Round

Exit Style

Dual Out Rear

Finish

Natural

Gasket Or Seal Included

No

Grade Type

Performance

Hangers Included

Yes

Heat Shield Included

No

Inlet Diameter

2.50

Inlet Type

Weld-On

Mounting Bracket Included

Yes

Muffler (Left) Type

Chambered

Muffler (Right) Type

Chambered

Muffler Body Material

409 Stainless Steel

Muffler Body Shape

Oval

Muffler Finish

Black High-Temperature Paint Finish

Muffler Flanged Inlet

No

Muffler Flanged Outlet

No

Muffler Inlet Connection

Slip-Fit

Muffler Outlet Connection

Slip-Fit

Muffler Outlet Quantity

1

muffler part number

Kit Only

Muffler Quantity

2

Muffler Series

Super 44 Series

Muffler Type

Chambered

Pipe Color

Silver

Pipe Material

409 Stainless Steel

Product Type

Exhaust System

Sound Level

Aggressive / Moderate

Spring Bolt Kit Included

No

Sub Category

Exhaust and Tail Pipes

Tail Pipe Quantity

2

Tail Pipe Quantity

Dual

Tail Pipe Tapered Outlet

No

Type

Crossmember-Back

Valve Included

No

Valve Type

Not Applicable

Warning

California Proposition 65

Fast and simple process.

great service and fast shipping. Low pricing too.

Ordered Monday and shipped out Tuesday. Fast shipping and cheapest price I found online. Would order again especially with the free shipping.

Thanks for having the part I needed, and at a really good price!

Ordered it Friday had it at my door on Wednesday! They also had the cheapest prices of all reputable sellers.

Really handy being able to pay through Amazon.

First time like it so far

Quick easy checkout.

Easy site to use and order from. Autoplicity has friendly customer service and also they had the CHEAPEST price on the exhaust tip that I ordered for my truck. I am a very happy customer!!!

Good

I entered my discount code 2offtotal and it did not remove 2% of the price. It was less than10 so not a big deal, but it would have been better if it worked.

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