Measuring in at 2.5″ the stock exhaust system's diameter is not exactly small, but a larger diameter exhaust could definitely help our EcoBoost's output. With the stock exhaust system our F150 put down 256.9 horsepower and 339.3 foot pounds of torque.
Any tuning project with a forced induction vehicle needs a good exhaust system. This is a vital component for our build goals too. Given how many 600+ HP F150 examples are out there, we decided a target of roughly 500 WHP would be a reasonable longterm goal. This truck will not have regular daily driver duties, but it would still need to tow and drive reliably on long road trips. We all know that a three inch ID mandrel-bent exhaust is the de facto standard for most every modified turbo-powered car these days. That sounded fine for our F150 too — until our friends at MagnaFlow told us about their new 4” stainless steel system!
The 4″ MagnaFlow exhaust system we decided to go with is part number 19335
. The system uses 409 stainless steel for durability and the tubing is completely mandrel bent in order to maximize exhaust flow.
The double wall MagnaFlow exhaust tip is 5″ in diameter and 13″ long. Our stainless exhaust tip may never look this good again inside and out, but the polished finish will ensure years of great looks with minimal upkeep.
The muffler section is also polished to a high shine and is another place to inspect MagnaFlow's excellent weld quality.
With the stock system (top) off the car we can see it is reasonably sized, but the 4” MagnaFlow system really makes it look small in comparison.