Installing Borla Exhaust System - Cold Fusion
Warming Up A Winter-Beater
From the November, 2009 issue of Modified Mustangs & Fords
By Dale Amy
Photography by Dale Amy
We suspect that, like us,...
We suspect that, like us, many of you drive a Fusion every day. Though its appearances in these pages will be few and far between, we plan to share our experiences with some aftermarket Fusion enhancements, starting with an exhaust system. Check out those manly tips!
Tech | Exhaust Upgrade
Practicality sometimes gets in the way of driving a Mustang on the daily commute, so many of us have to resort to more prosaic forms of transportation (but that's OK: it keeps the "toys" fresh for weekend or after-hours enjoyment). In my own case, the latest driver is an '09 Fusion SEL V-6, and I suspect I'm not alone amongst the readers of this magazine in choosing Ford's midsize, agile, and affordable sedan for its many practical virtues. Not to mention that it's a pretty handsome ride. Though I don't really need its four doors and generous rear seat area, that huge trunk swallows all my photo gear and the Fusion's available all-wheel drive system is just the ticket for the oft-inclement weather of my northern location. Good weather or bad, one can never have too much launch traction.
Of course, being a magazine type and life-long gearhead, I couldn't very well leave it stock, could I? And in case there are others out there who find themselves in the same position, we've decided to report every once in awhile on our Fusion's upgrades-which, in keeping with its daily-driver role, will be nothing radical or exotic; just basic and hopefully cost-effective mods that will embellish its stylish and sporty character without detracting from its comfort or practicality.
Our first upgrade is to the utterly silent factory exhaust-a project immediately complicated by our SEL's all-wheel drive, since we could find no one making a system for the AWD Fusion. So we improvised with the help of a talented fabricator. We started with Borla's 304 stainless kit for the front-drive 3.0L Fusion and modified it as necessary to work beneath our AWD belly.
Before delving into how this was accomplished, a quick word on what we didn't want and that was a noisy, droning beast of the sort that turns highway drives into sonic torture sessions. So with that in mind, for those of you considering such an exhaust upgrade to your own Fusion, read on . . .
Our starting point was Borla's...
Our starting point was Borla's nicely crafted kit for front-drive Fusions, consisting of a pair of muffler/tailpipe sections, a Y-pipe, and an intermediate pipe with resonator. The pipes are of factory diameter, but with less restrictive silencers Borla claims the setup will flow an impressive 241 cfm better than the stock system while weighing less. The all-stainless steel system is PN 140184 and retails for $1,040.99.
Though the muffler/tailpipe...
Though the muffler/tailpipe sections will work fine out of the box, the intermediate- and Y-pipes will not simply bolt up to an AWD Fusion, which has a rear driveshaft and differential that demand a unique exhaust routing. Note that our factory intermediate pipe (and the front resonator) hangs below the driveshaft tunnel and bends around the rear diff whereas a FWD Fusion has its intermediate pipe/resonator tucked up into the driveshaft tunnel, and routing around a conventional fuel tank (in the previous photo, you can see that the AWD version has a Mustang-style saddle tank). So it's this intermediate pipe and the resulting different bend geometry in the rear Y-pipe that cause the incompatibility. (Note that this shot is of a four-cylinder FWD, but the intermediate pipe routing is the same as on a V-6.)
After mulling over the situation...
After mulling over the situation with Polito Ford's skilled fabricator, Bart Slot (he builds race cars for fun), we decided to control costs and decibel levels by retaining the factory resonator and most of the intermediate pipe, cutting it off just ahead of the system's tuned mass damper. While it would certainly be possible to fabricate up a whole new intermediate pipe, that would require a pricey chunk of new stainless tubing. (For those wanting a more aggressive exhaust note, an option is to cut the stock resonator out of the factory intermediate pipe and weld in the freer-flowing, and louder, Borla replacement.)
Here's the section of factory...
Here's the section of factory exhaust that will be replaced. Note the enormous mufflers and relatively small tips.
Bart then hung the Borla mufflers,...
Bart then hung the Borla mufflers, slid them in place on the kit's Y-pipe, and positioned the system with an adjustable exhaust stand. You can see that there was definitely work to be done to somehow mate the Y with the factory intermediate pipe.
The Y-pipe's central hanger...
The Y-pipe's central hanger (arrow)-useful only on FWD applications, as shown in our earlier comparative photos-has to come off to clear the differential. Proximity to the diff also required slight clearancing of the Y-pipe, just forward of its junction section. You can also see a black marker line that Bart has drawn on the Y-pipe (just forward of the support stand); this is where he decided to cut it to best facilitate joining the Y up with the intermediate pipe.
Here the Y-pipe has been cut,...
Here the Y-pipe has been cut, and the top of the pipe recontoured to provide clearance around the differential housing. That may not look like much clearance, but it's enough. We've had absolutely no contact between the exhaust and the rear diff since the installation.
Bart's frugal scheme was to...
Bart's frugal scheme was to use nothing but the Borla kit's unused pipe sections to complete the system. These would be cut as needed. Here, the piece he just cut off the Y-pipe has been trimmed shorter, slipped over the intermediate pipe, and reoriented to best bring it in line with the remainder of the Y-pipe, leaving just a small gap to be filled. The tricky part was that this gap wasn't straight, and required a curving section to join the two pipes-thus explaining the need for calipers and concentration.
Here, those careful measurements...
Here, those careful measurements have been transferred to an existing mandrel bend in the Borla kit's unused intermediate pipe. Bart then cut, trial fit, and trimmed this curving patch section to precisely fill the gap. It's this ability to think in three dimensions that makes for a great fabricator.
Initially tack welded in place,...
Initially tack welded in place, the patch perfectly fills the gap between pipes. Bart then removed the reconfigured Y-pipe and finished welding the joints before reinstalling and clamping everything down.
The finished system utilizes...
The finished system utilizes all the factory rubber hanger points. You can see that the cylindrical Borla mufflers take up far less space than their factory counterparts (and are no doubt lighter). Though the system probably frees up some power, we can't quantify the amount, since there are few chassis dynos local to us that will work with AWD.
The system looks much better...
The system looks much better than stock, with its polished oval tips nicely filling the similarly shaped cutouts in the rear fascia. And the sound is just right-a surprisingly deep, smooth, and sophisticated note without any raspy edges, annoying resonances, or highway drone. We suspect that keeping the factory resonator was a wise choice for our desired sound level. So take heart, AWD Fusion owners: even though you can't buy one off the shelf, some skillful fabrication can net you a great exhaust system.