Boss 302 Exhaust - Sides & Sounds
From the August, 2012 issue of 5.0 Mustang & Super Fords
By KJ Jones
Photography by KJ Jones
We've certainly had our hands full staying abreast of upgrade hotness. And, of course, with Coyote-powered Ponies being all the rage, the lion's share of new bolt-ons being produced these days is dedicated to '11-'13 Mustang GTs. While most of the components we've studied thus far have been legitimate performance enhancers, occasionally we hear about bits that are more superficially appealing.
Ford Racing Performance Parts recently hipped us to its new exhaust setup for '11-up Mustang GTs, a bolt-on replica of the side-exit tubes that are factory installed on Boss 302s, and we found the concept cool enough for us to put one on. The stainless-steel exhaust (PN M-5220-MB; $795) joins FRPP's other Boss pieces, which are making their way onto standard GTs. The Boss 302 upgrades bring back fond memories of the days when cloning specialty Mustangs (such as '93 Cobras) was popular.
While we're not out to fool anyone with this effort, we have to say right now that the new Boss 302 exhaust adds a distinct and unique rumble to a Coyote's exhaust note, especially once the attenuation disc/restrictor plates are removed.
Here we cover the exhaust exchange performed by Ricardo Topete and Eddie Zapata of GTR High Performance. While this exercise certainly can be performed by do-it-yourself-minded (and capable) enthusiasts, we suggest putting the job in the hands of professional installers, as shops typically are better equipped for below-chassis efforts.
Horse Sense: As '13 Mustangs hit the lots, we really have to be thankful that even when times were tight--only a few short years ago, as a matter of fact--aftermarket manufacturers like the folks at Ford Racing Performance Parts pushed forward with a bevy of cool bolt-on upgrades for Coyote-powered 'Stangs.
Baseline and dyno runs for this effort were performed largely for grins and curiosity satisfaction. However, when it was all said and done, GTR's Dynojet presented data that confirms adding Ford Racing Performance Parts' Boss 302 side-exhaust and mufflers actually does increase rear-wheel horsepower and torque on a bone-stock Mustang GT.
As you can see in the accompanying graph and chart, this is not a bolt-on that increases performance by leaps and bounds. However, when it comes to sound differences, the system (with accentuation discs removed) definitely will set apart the '11-up GTs that it's installed on.
Here is a final look at the...
Here is a final look at the bone-stock exhaust equipment on Salvador's 'Stang. Of course, the OEM catalytic converters remain in place. The combined efforts of Ricardo and co-technician Eddie Zapata had the stock tubes off in no time.
Ford engineers created this...
Ford engineers created this quad exhaust system (a traditional H-pipe with secondary discharge tubes on each side) to establish a signature exhaust tone for Boss 302 Mustangs. With this setup, exhaust exits through the rear pipes and via the smaller-diameter side tubing.
This is a closer look at the...
This is a closer look at the side-exit (we call them "kicker") pipes that sit just before the end of the discharge tubes.
True to OEM form, kickers...
True to OEM form, kickers in the Ford Racing pipe also feature the same step-down/step-up section. We can only guess that sound modification is the purpose of the diameter reduction.
The Boss 302 side pipes feature...
The Boss 302 side pipes feature polished stainless tips that are contoured downward. Unfortunately, however, once the system is fully installed, the turndowns are not really visible when you're looking at a 'Stang's profile.
Just beyond the block plates...
Just beyond the block plates lie Ford's attenuation discs on each kicker and thin stainless gaskets which are reused. We tested the system with and without the restrictor plates, and noticed a distinct audible difference between the two configurations. Check out the sidebar for details on the performance variances.
Factory H-pipe clamps are...
Factory H-pipe clamps are reused; a few swings of a rubber mallet may be necessary for dislodging them from the OEM tubes.
The Boss 302 pipe features...
The Boss 302 pipe features 1/4-inch-thick steel-block plates that allow the system to be used in standard/stock-exhaust fashion if desired. The plates must be removed before attaching the side-exit pipes.
When installing the side pipes,...
When installing the side pipes, the hard-plastic skid plates below each seat well must be removed.
The super-restrictive discs...
The super-restrictive discs feature holes for exhaust gas and sound discharge. From a sound perspective, the Boss-modified GT maintained a fairly quiet rumble with the restrictors in place. However, once Ricardo removed the plates, the 'Stang took on the exhaust note of a real-deal Boss 302.
We honestly had no expectations...
We honestly had no expectations of how the Ford Racing Performance Parts' Boss 302 side exhaust system would affect power and torque on Salvador's bone-stock (2,500 miles) 'Stang, so dyno testing was done with and without attenuation discs.
Here is a graphic look at...
Here is a graphic look at the Mustang's stock performance and the gains, if you will, with FRPP's Boss 302 exhaust kit in place (restricted and not restricted). The bottom line? The increases are relatively small. However, they are increases nonetheless, and gained without any tuning.
While the FRPP Boss 302 side...
While the FRPP Boss 302 side exhaust doesn't install in minutes, it isn't too daunting an operation. The system bolts in place, just as a stock H-pipe does, and the side pieces are secured in factory locations.
Installing the Ford Racing...
Installing the Ford Racing upgrade mufflers requires removing clamps from the OEM cans. Tack welds must be cut to get the clamps off of the stock pieces.
There really isn't much to...
There really isn't much to bolting the cans in place, as fitment is spot on.
The FRPP mufflers are installed...
The FRPP mufflers are installed using OEM hangers and aforementioned clamps.
Each muffler is nicely finished...
Each muffler is nicely finished with a polished Ford Racing-embossed stainless tip. Aligning the muffler tips requires two people (one spotter and another for making the actual positioning adjustments), but when done properly, it really makes the only visual portion of the completed installation look good.