This is the Flowmaster Force II True Dual Cat-Back Exhaust for the 2005 through 2009
V6 Mustang.
You're gonna wanna check this out if you're looking for more of a true-dual exhaust setup
that'll get rid of your factory Y-pipe, re-use your stock cats, and give you stainless steel
materials.
You have some options when it comes to dual-exhaust cat-back styles.
Some options just bolt right up to the factory Y-pipe, some options completely replace the
factory Y-pipe.
And others, like this one, maintain part of the factory Y-pipe but eliminate the Y portion.
This cat-back will require you to cut your Y-pipe after the cat, so you'll maintain the
front half but eliminate the rest of it.
Then the Flowmaster mid-pipe will bolt up and convert you over to a true-dual exhaust
setup.
Now, because there is some cutting involved, the install for this will be a two out of
three wrenches on the difficulty meter.
The real down-and-dirty facts about this cat-back are that this is a 2.25-inch 409 stainless
setup with 3.5-inch polished stainless steel tips.
You'll get this X-pipe, as Flowmaster calls it, and the Flowmaster 60-series mufflers.
As far as sound goes, because you are keeping your stock cats and part of that stock Y-pipe
and combining it with the Flowmaster X, you can expect a bigger change in sound than what
you'd get with a setup that just attaches to the stock Y-pipe.
You aren't eliminating any cats, though, so keep that in mind.
Overall, I'm gonna call this a three out of five on the loudness meter, with one being
a quiet upgrade and five being a loud upgrade.
You'll also need to modify your rear bumper for the second exhaust tip.
If you didn't want to cut your stock bumper, you could always pick up a GT bumper, but
most people just modify their factory bumper, and the cat-back comes with a template for
you to guide where you're cutting.
When it comes to price, you're looking at spending just over $780 for this cat-back.
This does make it one of the more expensive options, but you have to keep in mind the
design of this cat-back and that it's one of the more true-dual setups, as opposed to
having another upside-down Y-pipe that bolts up to the factory Y.
Of course, you're getting quality with the stainless steel materials as well as the Flowmaster
brand name.
The install for this cat-back is a two out of three wrenches on the difficulty meter,
because you will need to cut your factory Y-pipe after the cat.
You can expect the install to take you a few hours, two or three, and we'll send you guys
over to an install bay now to show you how it's done.
All right, now that we have the car up on the lift for this install, we're gonna start
off with spraying everything down.
Our car has a couple of miles on it, yours probably does too.
So go ahead and hit all those hangers and all those nuts and bolts with a little bit
of PB Blaster WD-40.
All right, so with everything oiled up, the first step is removing the factory muffler
right here.
It's held on by one rubber hanger and isolator, and then you have this clamp right here holding
it to our over-axle pipe.
Now, our clamp here has definitely seen some miles.
Normally we'd be taking this bolt out with a 14-millimeter socket.
Its already loosened for us.
However, this clamp's a little rusty, so I'd recommend a big old pry bar so you can pull
this clamp open and pull the muffler off the flow tube.
All right, with the clamp connecting our over-axle pipe to our muffler loosened, it's time for
us to get the muffler itself off the pipe.
Now, again, if your car has seen some miles, it might be seized up pretty good.
So you're gonna have my two favorite tools, a mallet and a pry bar, to try to get some
leverage and tap this thing loose.
All right, so we tried to pull our muffler off our over-axle pipe, but our worst fears
were confirmed.
It's a little bit too rusty.
So we need to get a little bit of leverage.
Now, there's an easy way to go about this.
You can actually remove the rear-most hanger on the muffler.
That's gonna allow you to drop it down and twist it free.
There are two bolts up here on this hanger.
They're supposed to be 13 millimeters.
If rust and age have eaten away at 'em a bit, you can step down to a half-inch.
So, we're gonna go ahead and remove that hanger now.
All right, so with our rear-most hanger removed back here, we actually have a lot more play
on our muffler now.
The last step to freeing the muffler up completely is to pull the muffler hanger out of this
isolator up here.
Pretty simple, once you have the rear-most one removed.
Just take a pry bar, push it against the rubber isolator, and you should be able to push it
out as well.
All right, so with that second rubber isolator freed up, now you should have enough leverage
to pull your muffler out.
There's still one more hanger back here, but it doesn't have that bulb end on it, so the
actual metal piece should slide in and pretty easily.
So, at this point, it's just a matter of using some brute force to get that muffler off that
over-axle tube.
So, with our muffler removed, it's time for us to remove the over-axle pipe/flow tube.
It's held on with this clamp right here, and you've got two 15-millimeter bolts securing
it.
All right, so, as has been the case with our install thus far, these are pretty rusted
and seized-up.
Now, our 15 kind of started to strip a little bit, so we backed off.
We're gonna step down to a 9/16ths, and that should do the job.
With those bolts removed from our clamp, it's still seized up here pretty good, so we're
gonna hit it with some penetrating oil, and we're gonna take our pry bar to it.
That way, we can open it up a bit, and this pipe should slide off the Y-pipe.
All right, so now that we brute-forced our stock flow tube off of our cat-back here,
we're gonna go ahead and take the AccuSeal clamp off, and this is the only part that
we're actually gonna be using with our new exhaust system.
Now, I highly recommend you take some wire brush or maybe some steel wool, definitely
take some penetrating oil, and clean out inside of this clamp.
That way, it slides on nicely to the original pipe and the new pipe.
All right, so, our stock cat-back is off the vehicle, and we know we're free and clear
to install our new cat-back.
But, before we do that, we have to cut into our bumper cover.
Obviously, you know that the factory V6 only comes with one cut-out.
It's very easy to do the second cut-out here.
You can find a template online, that's exactly what we did.
So, we're gonna go ahead and mark ours up with some permanent marker, and we're gonna
go ahead and start cutting.
All right, so, now with our template marked up here, there's a couple of ways you can
cut into the bumper.
Use a die grinder or a SAWZALL, but honestly, an air saw like this which goes at a higher
RPM is gonna give you the most control, and it's gonna cut slowly but consistently.
That way you make sure you have a nice, clean cut that you can polish up later.
All right, now that we have our hole roughly cut out, we're gonna go ahead and polish it
up here with one of our air Dremels.
Now, as you saw, I cut a little bit less than I needed to.
That way, when I polish it up with this, it's gonna be the perfect size.
It won't have any of these burrs or little nasty, crusty bits on there.
All right, so with that hole polished up, if you have any leftover marker, just go ahead
and take some rubbing alcohol.
That'll come off very easily.
As you're polishing that up, just take your time, kind of benchmark against the other
hole there, and you should be able to notice pretty easily if it's the same size or if
you need to take any bit extra off.
Now, that's all set up, so we're gonna go ahead and start installing our new exhaust.
So, we have our stock exhaust removed from our vehicle.
Now, the Flowmaster kit is really nice because you don't have to purchase a new hanger kit.
We're actually gonna be pulling off the furthest-most bracket from the rear bumper cover and transferring
it over to the driver's side, and our new mufflers are gonna be using one bracket for
each side.
They're gonna be using a 13-millimeter socket to remove this.
All right, so with that one bracket removed from the passenger's side, we're gonna go
ahead and transfer it over to the driver's side like I said.
Now, the V6 and the GT bodies are the same, so these holes are already drilled and tapped.
It's just a matter of using your original hardware and bolting it back up.
All right, with our hangers set up on the back of the car, the next step is cutting
our factory exhaust system.
Now, Flowmaster says you're gonna measure 14 inches back from each weld on each cat
and make your cut.
We're gonna go ahead and go right on the center of the rib of the weld itself.
We're gonna polish up all the burrs, and if we have to, we'll cut a little bit more off
to make our new X-pipe fit.
All right, with our factory exhaust cut, we are now set up to start our install.
We're gonna start off with the X-pipe included with the kit.
You're gonna wanna make sure the Flowmaster logo is facing down.
And to make this even easier, even though we de-burred everything, we're gonna spray
these pipes up with some lubricant, make it easier for us to get these pipes on.
All right, we'll go ahead and set our clamps up like so, then we can slide our pipes on.
All right, now it might be a little bit of a tight fit getting the X-pipe on.
So once you have it snugged up, go ahead and take a soft dead blow on the back end of it
and tap it into place.
All right, so now our X-pipe is pushed up snug onto the pipes we just cut.
Now, when you put the X-pipe on here, you might notice that it's touching your driveshaft.
And that's okay.
Remember, your rear axle is not under load if you're on a conventional lift or if you
jack stands aren't on the axle.
When you lower the car, you'll have plenty of clearance here.
Either way, grab two clamps, put them on the end of the X-pipe, and then grab your over-axle
tubes, and we're gonna install those next.
All right, so now both of our over-axle pipes are installed.
The next step is setting up this one little hanger here for the driver's side muffler.
You're gonna use one of the factory holes in the body, and they provide you with the
self-tapping screw so you can get this into place.
All right, with our over-axle pipes set up and that last hanger set up, we're gonna go
ahead and install our axles.
It's real simple, you're just gonna slide the flared end of the axle tube over the axle
pipe.
And to make things easier, I'm gonna go ahead and spray everything down, including the rubber
isolator and the pipe itself.
All right, so our muffler is hung and in place using our rear-most isolator.
Gonna go ahead and re-use this smaller rubber isolator for these two little hangers right
here as well.
All right, so our passenger side is done.
We're gonna go ahead and do the same thing on the driver's side.
Now, you noticed in the kit there is a little red rubber isolator, and that's for the hanger
that we just installed.
So, go ahead and follow the same steps, throw your muffler up there, and then slide that
red rubber isolator on.
All right, now both of your mufflers are installed and hung.
Now it's just time for you to make sure that none of your tubes are touching anywhere on
the car.
That way, you don't get any drone or any unnecessary rattling.
Once you've verified everything's lined up nicely with the tubes, and as well as the
bumper cover itself, you can tighten down your clamps.
You can use a 15-millimeter socket for all of these.
All right, so with all your clamps tightened up, that actually wraps up our review and
install of the Flowmaster Force II Cat-Back, fitting your '05 to '09 V6 Mustang.
I'm Travis, thanks for watching, and for all things Mustang, keep it right here at americanmuscle.com.