Force Multiplier: Sprucing Up An F-150 With Flowmaster And ACCEL

If you can’t remember the last time you did a tune-up on your rig, chances are it’s time to give it one. If we’re being honest, keeping the engine running is more than just doing oil changes and coolant flushes. The hardware will wear down over time and perform worse than it did from the factory.

It’s important to note that off-roading exposes all sorts of contaminants, shocks, and wear to the equation. Chad Scott, an avid off-roader in Rancho Cucamonga, California, knew all too well the kinds of abuse his 2013 Ford F-150 has endured. To help breathe new life into his truck, we enlisted the help of Holley brands Flowmaster and ACCEL to address four major areas – spark plugs, ignition coils, intake, and exhaust.

We were excited to upgrade the exhaust, intake, spark plugs, and ignition coils on this F-150.

Once these parts are replaced with new life from Flowmaster and ACCEL, the F-150 will be like a brand new machine. Not only will Chad have the confidence to keep his truck going for the long haul, but he’ll also enjoy the added benefit of a new exhaust note.

Details On The Parts

Our project made use of four distinct parts to reinvigorate the 5.0-liter V8. From Flowmaster, we sourced a FlowFX cat-back exhaust system (PN 717864) and a Delta Force performance air intake (PN 615127). From ACCEL, we sourced eight HP copper spark plugs (PN 579) and a set of Super Coil ignition coils (PN 140060B-8).

To help us understand more about these parts and what they bring to the table, we spoke with Holley’s Digital Content Manager, Evan Perkins. We kicked off the conversation by talking about vehicle maintenance and how Holley brands like ACCEL bring vehicles back to life.

To attain better spark and voltage, we went with ACCEL Super Coil ignition coils and HP copper spark plugs.

“Modern engines have a hard life and truck engines that much more so,” said Perkins. “Staying on top of engine maintenance is key to ensuring an engine will have a long service life and deliver maximum performance along the way. ACCEL’s line of coils, spark plugs, spark plug wires, fuel pumps, and various other high-performance service parts are designed to be direct replacements for worn factory components and provide a bump in performance.”

HP copper spark plugs from ACCEL would restore lost spark and help ensure better combustion.

Going into greater detail, Perkins pointed out the ACCEL spark plugs’ use of copper instead of iridium or platinum. “Copper is the industry standard material for performance spark plugs,” said Perkins. “It is an incredible conductor, which means it delivers a very hot spark and runs cooler in the combustion chamber.”

ACCEL’s Super Coil ignition coils were the ideal choice to pair with these elite spark plugs. “ACCEL Super Coils feature construction intended to exceed OEM quality while providing a hotter spark,” commented Perkins. “Each coil uses specialized silicone magnetic steel cores surrounded by precision wrapped windings. The coil bodies are molded using a high di-electric strength material and the housings are filled with a specialized, high-temperature epoxy. The epoxy increases thermal conductivity and helps resist shock, vibration, and chemicals found in engine bay.”

This Flowmaster exhaust system touts a FlowFX muffler. As a straight-through muffler, we could expect to hear a much more noticeable exhaust note on the F-150.

Now that the engine was getting some solid replacement parts from ACCEL, we knew it could get even better with some auditory and potency upgrades as well. This was where the new cat-back exhaust and performance air intake came into play.

The Fl0wFX cat-back exhaust system promised a better exhaust tone than the stock system. “The FlowFX line is a straight-through style muffler,” explained Perkins. “It’s going to deliver a louder, more aggressive tone than a comparable chambered muffler. What’s more, this kit is extremely compact, which makes it a great fit for vehicles with limited space underneath. This kit is also made from 409S stainless steel, so it will be extremely corrosion resistant to boot.”

To round out the engine upgrades, we also ordered a Delta Force performance air intake system from Flowmaster. This kit provides more air through the throttle body than stock, enhancing power and also offering up some sweet sounds while revving.

And last but not least, we wanted to check out what the Delta Force performance intake system would offer this F-150. “Like all of our intakes, it is designed to feed the engine fresh, cool, air at a higher flow-rate than the factory intake,” said Perkins. “The Flowmaster Delta Force cold air intake features a serviceable, lifetime, high-flow, eight-layer filter. We design these systems to be 100-percent bolt-in ready. Also, they deliver up to five percent more power and torque than the factory system.”


Once we had all of our parts accounted for, we got started with the engine parts. With the hood open, we surveyed the intake and located the spark plugs and ignition coils on the engine.

We started on the intake. Chad and his buddy, Robert, took apart the intake box and tubing leading to the throttle body. Since the throttle body was exposed, Chad opted to use some cleaning compound on it. This cleared out the grit and grime that had collected over the years.

After deconstructing the stock intake, Chad went ahead and cleaned up the throttle body since it was exposed.

On the stock intake tube, Chad removed the MAF sensor. Robert advised using MAF cleaning spray to get rid of any gunk on the sensor. After doing so, Chad installed the sensor into the new Flowmaster intake tube.

Chad moved onto assembling the new intake box. This was where the new filter would rest. Flowmaster provided weather stripping that would seal the box from air leaks once fully installed. Chad applied the weather stripping, and installed hose couplers for the tubing. On the bungs for the PCV and EVAP nozzles, Chad applied nylon tape to help seal them in the new intake tubing.

Chad applied the gasket to the airbox to help it seal correctly once installed. He also wrapped the EVAP and PCV nozzle threads with nylon tape. Once that was done, he put together the Delta Force intake inside the engine bay.

Chad took the new intake and situated it in the engine bay. After some jostling, the parts lined up and hooked up with several hose clamps. With that, the new Flowmaster intake was hooked up.

We turned our attention toward the spark plugs and ignition coils.

We moved onto the ignition coils and spark plugs. These parts, especially the spark plugs, required a gentle touch. Robert guided Chad along, pointing out how to unplug the coils and remove them from the engine.

Once all eight coils came out, Chad used his air compressor to blow out any dust and dirt inside the holes. We were now ready to get after the spark plugs, but before we did that, Robert took a gapping tool and checked all of the ACCEL spark plugs.

After removing all eight coils, Chad used compressed air to blow out any dust inside before removing the spark plugs. Meanwhile, Robert checked the gaps on the ACCEL spark plugs. Satisfied, he gave each one anti-seize compound on the threads and installed them into the engine.

From what Robert and Chad found on the internet, the proper gap was between .049-.053 inches. Robert ensured the gap was near .050 inches and coated them with anti-seize grease. Chad grabbed his socket wrench and equipped it with a long extension and magnetic socket. Using careful pressure, he extracted all eight of the spark plugs without issue.

Chad installed the spark plugs and torqued them properly. He then installed the new Super Coil ignition coils and plugged them back into the connectors. The moment of truth arrived – would the F-150 crank and fire?

Securing the new Super Coils to the engine.

Chad got behind the wheel and put the key in. Cranking it, the F-150 took a moment as it gathered the new feeling of the Flowmaster intake. Then, it fired right up! Chad gave it a celebratory rev and shut off the engine. We took lunch and waited for the exhaust to cool down.

Removing the stock exhaust as one piece was tricky, but it all worked out in the end.

The exhaust was straightforward and thankfully didn’t require any cutting. After propping the rear tires on ramps, Chad and Robert could slide in and out using creepers. They undid the hangers on the stock exhaust and began rotating it until it came out all as one piece over the rear axle.

From there, Chad attached exhaust piping to the back of the catalytic converter. He rotated it until it was clocked correctly. He then installed it onto the exhaust hanger and hooked up the new FlowFX muffler.

Installing the new exhaust was straightforward. The end result was well worth the effort!

Robert, meanwhile, guided the new tailpipe over the rear axle until Chad had a grip on it. He used the provided clamps to join the two together as Robert held up the weight. Finally, all that was left was the exhaust tip, which got clamped down. All told, the guys finished everything on the F-150 before lunch. Not too shabby!

Testing It Out

Now that the truck was back up and running, Chad had to take it out for a test drive. Or was it a joy ride? Chad was all smiles as we headed to an open street near his house to put the F-150 through its paces.

Getting on the throttle, we could immediately feel a difference. The exhaust produced a throaty growl all through the power band. It resonated inside the cabin. Easing off the throttle, the sound faded as it should, and remained at a tolerable volume under normal side street speeds.

Taking the F-150 out for a test drive after the install, the truck had a new life to it. We could hear the exhaust whenever Chad got on the gas. It was a blast to ride around in.

“The difference between stock and upgraded is amazing on this truck,” Chad commented. “I’m impressed with how easy it was to take care of these modifications. The directions were easy to follow, and made it simple to remove and install everything.”

“The exhaust is definitely the highlight and the modification I’m most happy about,” he continued. “It gives a good rumble but it’s not overpowering any conversation or music playing inside the cabin.”

Following the installation, these parts proved that we’d completed the mission. The engine was running strong and making great notes thanks to the new intake. The exhaust, meanwhile, was loud when Chad gave it gas, and subdued when Chad drove normally. It was the best of both worlds.

If your truck, Jeep, or SUV is getting on in years and needs a refresh, Holley brands like Flowmaster and ACCEL are here to help. They’ll keep your rig running for the road ahead. Be sure to check out Holley’s website, and don’t forget to follow Holley on its Facebook page, too.

Article Sources

About the author

David Chick

David Chick comes to us ready for adventure. With passions that span clean and fast Corvettes all the way to down and dirty off-road vehicles (just ask him about his dream Jurassic Park Explorer), David's eclectic tastes lend well to his multiple automotive writing passions.
Read My Articles

Everything Off Road in your inbox.

Build your own custom newsletter with the content you love from Off Road Xtreme, directly to your inbox, absolutely FREE!

Free WordPress Themes

We will safeguard your e-mail and only send content you request.

Off Road Xtreme - The Off Road Magazine


We'll send you the most exciting Off Road articles, news, truck features, and videos every week.

Off Road Xtreme - The Off Road Magazine


We will safeguard your e-mail and only send content you request.

Off Road Xtreme - The Off Road Magazine


Thank you for your subscription.

Subscribe to more FREE Online Magazines!

We think you might like...

Diesel Army
Diesel Army
Street Muscle Mag
Hot Rods & Muscle Cars
Engine Labs
Engine Tech

Off Road Xtreme - The Off Road Magazine

Thank you for your subscription.

Subscribe to more FREE Online Magazines!

We think you might like...

  • dieselarmy Diesel Army
  • streetmusclemag Hot Rods & Muscle Cars
  • enginelabs Engine Tech

Off Road Xtreme - The Off Road Magazine


Thank you for your subscription.

Thank you for your subscription.

Off Road Xtreme - The Off Road Magazine

Thank you for your subscription.

Thank you for your subscription.