header-back

Flowmaster 817654 - Header-back System 409S - Dual Rear or Side Exit - Moderate/Aggressive Sound

rating-star review rating-star review 1rating-star review 2rating-star review 3rating-star review 4

$649.95

$722.95

You save: $73.00 (10%) off MSRP

Unavailable

This product is currently unavailable.

Check to see if this fits your vehicle

This part fits

  1. 1972 GMC C15/C1500 Pickup Base
  2. 1972 Chevrolet C10 Pickup Base 5.0L V8 cid:307 cc:5031
  3. 1972 Chevrolet C10 Pickup Base
  4. 1972 GMC C15/C1500 Pickup Base 5.0L V8 cid:307 cc:5031
  5. 1971 GMC C15/C1500 Pickup Base 5.0L V8 cid:307 cc:5031
  6. 1971 GMC C15/C1500 Pickup Base
  7. 1971 Chevrolet C10 Pickup Base
  8. 1971 Chevrolet C10 Pickup Base 5.0L V8 cid:307 cc:5031
  9. 1970 Chevrolet C10 Pickup Base
  10. 1970 Chevrolet C10 Pickup Base 5.0L V8 cid:307 cc:5031
  11. 1970 GMC C15/C1500 Pickup Base
  12. 1970 GMC C15/C1500 Pickup Base 5.0L V8 cid:307 cc:5031
  13. 1969 Chevrolet C10 Pickup Base 5.3L V8 cid:327 cc:5358
  14. 1969 GMC C15/C1500 Pickup Base
  15. 1969 GMC C15/C1500 Pickup Base 5.0L V8 cid:307 cc:5031
  16. 1969 Chevrolet C10 Pickup Base
  17. 1969 Chevrolet C10 Pickup Base 5.0L V8 cid:307 cc:5031
  18. 1968 Chevrolet C10 Pickup Base 5.3L V8 cid:327 cc:5358
  19. 1968 Chevrolet C10 Pickup Base 5.0L V8 cid:307 cc:5031
  20. 1968 GMC C15/C1500 Pickup Base 5.3L V8 cid:327 cc:5358
  21. 1968 GMC C15/C1500 Pickup Base 5.0L V8 cid:307 cc:5031
  22. 1967 GMC C15/C1500 Pickup Base 5.3L V8 cid:327 cc:5358
  23. 1967 GMC C15/C1500 Pickup Base 5.0L V6 cid:305 cc:5012
  24. 1967 Chevrolet C10 Pickup Base 4.6L V8 cid:283 cc:4638
  25. 1967 Chevrolet C10 Pickup Base 5.3L V8 cid:327 cc:5358
  26. show all...
Authorized Dealer

About this product

Part #: 817654

Flowmaster's American Thunder crossmember-back exhaust system for the 1967 - 1972 GM C10/C15 1/2 ton 2WD (Coil Spring) pickup truck is perfect for the person looking for moderate to aggressive sound levels with all of the performance benefits that you would expect from Flowmaster. This crossmember-back DOR/DOS (Dual Out Rear, Dual Out Side) system features dual Super 44 Series mufflers, 2.50 in. mandrel bent 409S stainless steel tubing and all the hardware necessary for a great fitting installation. (Stainless tips sold separately). This system is routed in a fashion that accommodates both long and short wheelbases with automatic or manual transmissions, and provides adequate clearance for substantially lowered vehicles. The exhaust system is covered by Flowmaster's Lifetime Limited Warranty.

More Details

Exhaust SeriesAmerican Thunder
Exhaust TypeDual
Exit PositionDual Out Side
Exit PositionDual Out Rear
Exit StyleStraight
Heat Shield AttachedNo
Inlet Diameter2.500 in.
Inlet Inside Diameter2.500 in.
MaterialStainless Steel
Muffler Count2
Muffler Part NumberKit Only
Muffler SeriesSuper 44 Series
Outlet Diameter2.500 in.
Outlet Outside Diameter2.500 in.
Single or DualDual
Sound LevelModerate/Aggressive
System TypeHeader Back
Tail Pipe Diameter2.500 in.
Tip Quantity0
TitleFlowmaster 817654 Crossmember back 409S - Dual Rear or Side Exit - Moderate/Aggressive Sound
Tubing Diameter2.500 in.
Additional Documents
  1. Certificate of Originpdf
  2. Installation Instructionspdf
  3. Warrantypdf

See what our community says about flowmaster products

product page reviews icon 0product page reviews icon 1product page reviews icon 2product page reviews icon 3product page reviews icon 4
What made you choose this particular product?
I was looking for a better flowing cat as well as piping as the factory piping was horrible for flow.
Is this your first time buying from this brand? Did you consider other brands?
First time Flowmaster purchase
Was it easy to install? Any installation tips that will help others?
I had my car mechanic install as my driveway isn't safe to work on the truck.
Once you've had a chance to use the product, did it meet your expectations?
Really smoothed out the power delivery of the engine. Doesn't feel like it's struggling to rev.
View on Shawn's build
Travis Pessina

293

Travis Pessina
2006 Dodge Charger
product page reviews icon 0product page reviews icon 1product page reviews icon 2product page reviews icon 3product page reviews icon 4
What made you choose this particular product?
Price, performance, sound is incredible
Is this your first time buying from this brand? Did you consider other brands?
Yes
Was it easy to install? Any installation tips that will help others?
Professional installed
Once you've had a chance to use the product, did it meet your expectations?
Good price for the performance
View on Travis's build
product page reviews icon 0product page reviews icon 1product page reviews icon 2product page reviews icon 3product page reviews icon 4
What made you choose this particular product?
I honestly like it really gives the truck a new sound and wakes it up some
View on Wadie's build
Timothy Moore

2.4k

Timothy Moore
2001 Volvo S60
product page reviews icon 0product page reviews icon 1product page reviews icon 2product page reviews icon 3product page reviews icon 4
What made you choose this particular product?
After doing a good deal of research on different mufflers, and running into Summit Racing Equipment's video on Flowmaster exhaust series comparison video, I decided on this Super HushPower 2 muffler, which ended up being the right choice!
What were you trying to accomplish by adding this product?
My old exhaust system was rusting out (but not severely), so I thought it would be a nice project to get rid of it in favor of a lighter, better-sounding custom setup. I wanted something very sporty, but not aggressive, or too loud.
Was it easy install? Any installation tips that will help others?
Mostly yes because this part of the exhaust project was easier to put up with than the glasspack--both before and after making changes. This one was a bolt-on both times. It is secured with v-bands in case I want to swap it out, or remove it easier when I want to do something in the rear, such as dropping the rear subframe, for example.
Once you’ve had a chance to use the product, did it meet your expectations?
At first, my expectations were rather mixed. It was a bit louder than I expected before installing the glasspack, and the raspiness was more of a thing before I rearranged the exhaust to have the muffler closer to the rear. Moving it to the rear gave it the more preferred low-tone, "burbling" exhaust note I was looking for, but either way, it always sounded good--especially with a glasspack. I was even told by a few people that it sounded like a V10, noticing how similar 5-cylinder and V10 engines sound!
Any additional comments?
Definitely a nice, lightweight, and not-too-loud option for custom exhausts! It is on the quieter-end of the Flowmaster exhaust aggressiveness spectrum after all.
View on Timothy's build
Connor Martin

66

Connor Martin
2015 Ford Mustang
product page reviews icon 0product page reviews icon 1product page reviews icon 2product page reviews icon 3product page reviews icon 4
What made you choose this particular product?
It sounded really good on the car
What were you trying to accomplish by adding this product?
Make the car more vocal but not obnoxious
Was it easy install? Any installation tips that will help others?
I paid someone to install it
Once you’ve had a chance to use the product, did it meet your expectations?
Yes it was worth every penny
Any additional comments?
Very deep sounding exhaust. 10/10 product
View on Connor's build
California prop 65 warningWARNING: Cancer and Reproductive Harm www.p65warnings.cs.gov

*Some manufacturer restrictions apply.

About Flowmaster

Manufacturer of performance exhaust systems, mufflers, cold air intakes, turbo boost modules, catalytic converters, race mufflers, headers and numerous exhaust accessories for late model cars, trucks, off-road, Jeeps, SUV’s, classic muscle cars, powersports vehicles and more. Flowmaster® gives you lots of exhaust choices with 12 designs of chambered mufflers, 3 styles of our exclusive “laminar-flow” mufflers and a new line of FlowFX “straight-through” performance mufflers, along with 5 sound categories of exhaust systems, giving you the customer, the power to custom tailor the sound of your vehicle whether you prefer mild, moderate or aggressive tones and sound levels.

shipping-worldwide from warehouse

we ship worldwide!

Based in California with 3 warehouses across the country, we’re sending out shipments everyday of the week, even Saturdays. Because your next mod shouldn’t have to wait.

+ FREE GROUND SHIPPING ON U.S. ORDERS OVER $99
Globe international shipping icon
Have a question? Ask an Expert!

Finding the best parts can be tricky

- but not to worry! Our team of experienced American Muscle, JDM, Euro, and off-road tuners are ready to answer your questions (as long as we’re not in the garage wrenching on our own builds).

Decorative testimonal quote icon

What do you get when you mix Facebook, Amazon, and your favorite online car forum? You get Wheelwell.com.

undefined supporting their testimonial

Hot Rod Magazine

Decorative testimonal quote icon

Wheelwell helps you organize all your stuff for your car, I’ve loaded all my cars on Wheelwell and you can see all the parts I’ve put in them and that may help you make a decision with your own build.

Matt Farah supporting their testimonial

Matt Farah

The Smoking Tire / The Drive

Decorative testimonal quote icon

This is an awesome new site where enthusiasts can get together and figure out what products work best on their ride.

undefined supporting their testimonial

The Truck Show Podcast