Revving up Performance with a New Manifold
As an avid auto enthusiast and hobbyist mechanic, I’m always looking for ways to extract a little more horsepower and torque out of my ride. Lately, I’ve had my eye on replacing the stock exhaust manifold with an aftermarket upgrade – and one name keeps coming up again and again: Flowmaster.
Flowmaster is one of the biggest players in the performance exhaust game, so I decided to dig into their exhaust manifolds to see what all the hype is about. In this blog, I’ll walk through everything you need to know if you’re considering upgrading to a Flowmaster exhaust header.
What Vehicles are Compatible with Flowmaster Manifolds?
One of the best things about Flowmaster headers is the wide range of vehicle makes, models, and years they cover. They offer direct replacement manifolds for popular domestic vehicles like:
- Ford Mustang GTs
- Chevy Silverado trucks
- Dodge Challenger
- Jeep Wrangler
But Flowmaster doesn’t leave import fans out in the cold – they also make exhaust manifolds for vehicles like:
- Toyota Tacoma
- Nissan 350Z
- Mazda Miata
- Honda Civic
Basically, if you drive anything remotely performance-oriented, chances are Flowmaster makes a direct replacement exhaust manifold for your ride. Their applications cover millions of vehicles from the 1950s all the way to today.
How Do Flowmaster Manifolds Improve Performance?
So why would you want to swap out your stock exhaust manifold for an aftermarket one anyway? In short: because the OEM part is designed for noise reduction and emissions, not power. By replacing it with a Flowmaster manifold, you can:
- Increase horsepower and torque: By improving exhaust flow, a Flowmaster manifold helps your engine breathe better and burn more fuel/air mix with each revolution. The result is more ponies and twist at the wheels.
- Enhance throttle response: More quickly removing spent gases from the engine improves cylinder filling for sharper off-the-line acceleration.
- Boost top-end power: Reduced backpressure at high RPMs enables your engine to put out max performance at the top of the tach instead of running out of steam early.
- Improve engine sound: A performance manifold gives your exhaust note a deeper, beefier tone that will turn heads as you roar past.
What Materials are Used in Flowmaster Manifolds?
Flowmaster uses heavy-duty 16-gauge mandrel-bent tubing to construct their exhaust headers. Mandrel-bending avoids crushing or kinking the tube during shaping, ensuring smooth exhaust flow.
The steel alloy provides increased temperature resistance and durability compared to stock manifolds. This is critical for handling the intense heat of exhaust gases right as they exit the engine.
To further manage under-hood temperatures, Flowmaster coats their headers in a metallic ceramic thermal barrier. This helps reflect heat away from the engine bay and keeps components like hoses, wiring, and plastic parts protected.
Can I Install a Flowmaster Manifold Myself?
One of the nice things about these direct replacement manifolds is that they utilize your vehicle’s factory mounting points and hardware. That means installation is very straightforward compared to a custom or “universal” header.
With some basic hand tools, a little mechanical know-how, and a Haynes manual for your specific vehicle, self-installation is definitely doable. Just be sure to have plenty of time set aside, as it can take 4-6 hours your first time.
If you run into any snags, be sure to reach out to Flowmaster’s tech support line – their experts can usually talk you through any difficulties. And of course you can always pay a professional mechanic or exhaust shop to handle the install if you prefer.
How Much Does a Flowmaster Manifold Cost?
Flowmaster exhaust headers range from around $300 on the low end, up to around $550-600 for their premium race-grade manifolds. Considering you can easily spend $800+ on custom fabricated headers, Flowmaster’s direct replacement design offers great bang-for-buck.
You’ll also save money on installation costs versus a custom job. When looking at the horsepower per dollar, a Flowmaster swap is one of the most cost-effective bolt-on upgrades you can make.
Are Flowmaster Manifolds for Cars or Trucks?
Flowmaster makes performance exhaust manifolds for both cars and trucks. In fact, some their most popular applications are for pickups and SUVs from GM, Ford, and Dodge.
So whether you’re driving a Mustang or an F-150, a Camaro or a Silverado, Flowmaster has you covered. Their truck manifolds feature retainer tabs and O2 sensor ports just like the factory units do.
How Does a Flowmaster Manifold Change the Sound?
One of the most noticeable changes when upgrading your exhaust manifold will be the sound. Flowmaster’s performance manifolds give your engine note a much more aggressive tone.
You’ll get more rumble and throatiness, especially at mid to high RPMs, as the free-flowing header eliminates restrictive baffles. It’s like music to a gearhead’s ears!
That said, it’s not obnoxiously loud either. Flowmaster balances performance and sound quality, so you get a bold exhaust note that turns heads, not one that just annoys your neighbors.
What Kind of Warranty Comes with Flowmaster Manifolds?
Flowmaster provides a limited lifetime warranty on all their exhaust components. That includes their direct replacement manifolds, ensuring you’re covered in case of any defects in materials or workmanship.
The warranty is fully transferable too, so it remains active even if you sell the vehicle. That can help resale value down the road.
Of course, general wear and tear or damage from accidents/impacts won’t be covered. But if the product itself fails, Flowmaster will provide a replacement manifold or equivalent product. Overall, great backing for peace of mind.
Where to Buy a Flowmaster Exhaust Manifold
You can find Flowmaster headers at many online retailers of aftermarket auto parts, including:
- Summit Racing
- JEGS
- AutoAnything
- CARiD
Brick-and-mortar auto parts stores may also carry a selection of Flowmaster manifolds. And you can always order directly from Flowmaster as well.
When shopping online, be sure to enter your vehicle’s exact year, make, and model to ensure you get the proper fit. Also double check the header style – some applications come in different designs.
Legal and Emissions Considerations
When modifying your vehicle’s emissions system by swapping exhaust components, you’ll want to be aware of legal regulations. Installation of aftermarket manifolds itself is generally not prohibited.
However, your vehicle may fail visual inspection or emissions testing in states that require it. Before installing a Flowmaster header, check your local laws to avoid any issues.
Some states allow exemptions for racing vehicles or off-road use. You may also be able to make modifications like adding second oxygen sensors to bring the vehicle back into compliance.
Maintaining Your Flowmaster Manifold
Fortunately, Flowmaster exhaust headers don’t require much periodic maintenance. Here are a few tips for keeping your manifold in peak condition:
- Allow the engine to fully cool before washing the engine bay to avoid thermal shock.
- Use soap and water to clean the header – avoid harsh chemical cleaners.
- Periodically check all mounting hardware for proper torque – re-tighten if needed.
- Watch for leaks or damage to exhaust gaskets.
- Remove built-up carbon deposits inside the manifold using a carbon scraper.
With its durable construction and thermal barrier coating, a Flowmaster manifold should provide years of performance before needing to be replaced.
When Do I Know It’s Time for a New Manifold?
Typical signs that your exhaust manifold should be replaced include:
- Visible cracks, leaks, or external damage
- Severely corroded or burnt out areas inside the manifold
- Loose mounting points or detached hardware
- Diminished performance gains
- Increasingly loud rattling or metallic sounds
If you notice any of the above, it could mean the manifold has become too corroded or damaged internally. Replacing it will ensure peak engine performance.
Does Flowmaster Include Installation Hardware?
Yes, Flowmaster manifolds come complete with all the necessary mounting hardware for your specific vehicle application. That includes flange gaskets as well as any bolts, nuts, studs, etc.
This makes installation much easier because you won’t need to source additional parts separately. Just remove your old manifold and bolt the new one right up using the supplied components.
Can Flowmaster Manifolds be Used for Racing?
Absolutely! While all their street manifolds offer great performance gains, Flowmaster also has a line of dedicated racing headers.
These TrackStar manifolds maximize exhaust flow capabilities for ultra-high horsepower builds. Perks include:
- Thick flanges to limit warping at extreme temperatures
- mandrel bends sustaining high internal velocities
- Optimized runner lengths for precise powerband targeting
- Additional bracing and reinforcement
So whether you’re taking your street machine to the strip or building a dedicated drag racing beast, Flowmaster has race-duty manifolds up to the task.
What Do Customer Reviews Say?
Looking at customer feedback, Flowmaster headers consistently earn 4+ star reviews. Owners rave about the increase in engine power as well as the improved throttle response and exhaust note.
Most users found the direct fit installation straightforward and were able to complete it themselves in a home garage without issues.
Some customers even tested their car on a dyno before and after – Flowmaster manifolds typically provide gains of 10-20 horsepower to the wheels on otherwise stock vehicles. Exact gains depend on the specific engine setup.
Overall, buyers describe Flowmaster as the gold standard in bolt-on exhaust upgrades and highly recommend their manifolds as a cost-effective way to unlock more power.
How Do They Compare to Stock Manifolds?
When compared to restrictive OEM exhaust manifolds, Flowmaster headers have:
- Larger diameter tubing for reduced backpressure
- Smooth mandrel bends instead of crush bent tubes
- Optimized runner lengths for scavenging effect
- Steel alloy construction vs cast iron prone to cracking
- Ceramic coating to handle intense exhaust heat
Add it all up, and Flowmaster manifolds simply outperform stock units across the board. While the factory exhaust is fine for regular driving, serious gearheads need an aftermarket manifold to unlock the engine’s true potential.
The Bottom Line on Flowmaster Headers
Based on Flowmaster’s proven track record in the performance market and the rave reviews from owners, their exhaust manifolds are one of the best bang-for-buck bolt-on upgrades I can make.
With a direct replacement manifold, I’ll be able to bump up the power and sound from my ride without breaking the bank. And I can handle the installation myself in my own garage.
So I’m putting a Flowmaster header at the top of my mod list. I can’t wait to tear into it on my next project day and start enjoying that sweet exhaust note and performance boost!
