Untitled 1986 2.3L dual exhaust conversion and 87-93 5.0L brake conversion page.

This page is intended to be a straight forward guide to what is required to install dual exhaust on a Fox body Mustang that came with single exhaust.  After the exhaust information, I'll also cover converting to 87-93 5.0L front brakes.  Most cars that have the single exhaust will also benefit from this upgrade, and it's an ideal time to do it since the brake system will already be opened.  In this case, the project car is a 1986 Mustang LX that started life as a 2.3L 4cyl.  Since early V8 cars had single exhaust, the conversion applies at least in part with only slight variations such as the H pipe, H pipe hanger, and dual hump crossmember. Some cars may require other changes, so I make no guarantees this information will apply.

The first problem to address is how to hang the passengers side muffler and tail pipe.  Fortunately all the drivers side hangers will support the drivers side of the new dual exhaust.  For the passengers side, the hangers have to be obtained.  They can be obtained new from various sources, or you can go cheap like I did and buy the pieces used.  The mounting locations were already present in my 1986 body, and the hardware (bolts, clips, etc) was obtained with the used brackets. 

The next obvious problem is the rear brake line.  On most single exhaust Fox Mustangs the rear brake line is anchored to the holes that our passengers side muffler hanger will use, and the line is positioned towards the passengers side of the axle tube.  This positioning places the flexible rubber brake line VERY close to where the new passengers side tail pipe will come over the axle.  The solution is to upgrade to the brake line used on cars with the 8.8 axle and dual exhaust.  These cars used a different support bracket also, locating the flexible rubber line at the middle of the rear axle towards the drivers side.  Unfortunately the bracket is a bit hard to come by.  Again I sourced the bracket, fitting, and retaining clip as a used assembly from the www.foureyedpride.com classifieds.  The steel rear brake line was ordered from an aftermarket vendor, along with new hardlines for the 8.8 axle.  The flexible rubber line was obtained from a discount auto parts store locally.  The new hose connects to the bracket with a banjo bolt.  The thread is 3/8-24, with an overall length of 1.26".  After research, I was able to purchase the bolt from a NAPA auto in a nearby town.  The part number is 83210, and they run about $4 and change, each.  I found that my local NAPA could only obtain these bolts in quantities of 5 or more.  The nearest store didn't stock them but the store in the next town did.  

Required parts:

Passengers side muffler hanger with rubber isolator & mounting hardware.

Passengers side muffler hook with self tapping bolts

Passengers side tail pipe hanger with self tapping anchor bolt.

Intermediate steel brake line.

Intermediate brake line support, with fitting, and keeper clip.

Banjo bolt.  Part# UP 83210

8.8 Axle steel brake lines.

8.8 Axle rubber brake line.

Once the parts are located, the install can begin.  I started by unbolting the old brake line support bracket from the body.  The new clip nuts slip into place and the new muffler hanger bracket can be bolted up to the body.  Since I was still waiting for the intermediate brake line to come in, I used a cut off wheel to trim the original brake line support bracket to fit inside the new muffler bracket.  Temporarily the bolts go through the brake line bracket, then the muffler bracket and into the clips on the body.  This sorta worked to get the car on the road, but after a couple weeks the passengers side tail pipe had rubbed the flexible rubber hose to the axle lines so much it was leaking.  I wouldn't recommend this shortcut. 

If you have the new intermediate brake line, now would be the time to install the new brake lines.  Remove the old lines from the axle and the body.  The intermediate brake line connects to a union on the passengers side of the firewall.  Unscrew this fitting, being careful not to let brake fluid drip on the paint.  To remove the old brake lines, you'll have to remove the passengers side fender liner, and it might help to loosen the fender mounting bolts.  Drill the rivets anchoring the line to the floor pan.   With the old line removed, snake the new line into place on the body, and anchor it to the existing holes in the body with 3/16" pop rivets.  Install the new support bracket to the mounting holes already in the sheetmetal and connect the new line.  At this point you can go ahead and remove the vent line from the axle and unscrew the axle lines from the wheel cylinders, and bolt on the new flexible rubber hose to the axle, and the new axle hard lines.  Once all the fittings are tight you can go ahead and bleed the brakes.  Now would be a good time to suck almost all of the old dirty fluid out of the master cylinder reservoir, and refill with clean fresh brake fluid.

Next, mount the passengers tail pipe hanger to the body.  There will be a dimple in the sheetmetal where the bolt will go.  Press in while turning the bolt and it should thread in.  There is some adjustment in the bracket, that will help locate the tail pipe correctly once installed.  Leave the bolt snug until the exhaust has been installed, and tighten it only after you're satisfied with the alignment of the tail pipe.

With the brake lines relocated, and the hangers in place, the new exhaust can be installed.  I started at the tail pipes, then the mufflers, and then installed the downpipe and joined everything in the middle.  With everything loosely installed, I adjusted the aligment to provide clearance and to locate the tail pipes properly.  When I was happy with the positioning, I tightened the clamps and took the car for a drive.  It took a few drives and adjustments to get rid of the various rattles from pipes bumping against the floor.

Rear brake parts and muffler hangers needed to convert to dual exhaust, not including intermediate brake line.

Intermediate brake lines, new and old. 

Stinger Performance 3" to dual 2.5" exhaust system.

Flowmaster Force II cat-back for 1986-93 Mustang 5.0 LX.

Stock 86 Turbocoupe downpipe and catalytic converter, side by side with the new Stinger parts.

Stock 2.3L muffler (2" inlet/outlet) next to new Flowmaster 50 series muffler (2.5" inlet/outlet).

2.3L 2" tail pipe, 5.0L Flowmaster 2.5" polished tail pipe.

Stinger exhaust Y-pipe modified with ball flanges to bolt up to 5.0 cat-back.

Old exhaust coming off.

New Flowmaster tail pipes mocked up.

New exhaust installed and adjusted.

Old Exhaust... 2.25" downpipe, with stock catalytic converter, 2" mid-pipe and tail pipe with stock turn down.

New exhaust... Stinger 3" downpipe to dual 2.5" Y-pipe, with Flowmaster 2.5" Force II catback with polished tips.

87-93 5.0L front brake conversion.

I probably wouldn't have done this upgrade, except that my stock 4cyl brakes were starting to become a liability, and a buddy had acquired the bulk of the parts only to sell the car he had planned to upgrade without getting them installed.  So since I got them for a super good-guy price, I felt it was worth while. 

This is a very straight forward conversion, with very little customization required.

Required parts:

1987-1993 5.0 V8 spindles, calipers, wheel bearings, dust shields, dust caps, etc.  Junkyard parts are fine as long as they're in good condition. 

1987-1993 5.0 V8 front struts

1987-1993 5.0 V8 front brake hoses

1987-1993 5.0 V8 front brake banjo bolts

1987-1993 5.0 V8 front brake pads

I got everything except the hoses and banjo bolts used.  The parts had been replaced shortly before they were removed from the parts car, and had very little wear. 

The install is straight forward remove and replace, except for the brake hose anchors.  The anchors needs to either be swapped for 5.0 parts, or just file/grind them till the 5.0 hoses will fit through them.  I did the latter, opening the hole till the hose would almost fit, and then notching the brackets to let the hoses key into place.  Once everything is installed, the front end will need to be re-aligned due to different geometry.  Bleed the brakes till clean fluid comes out of the bleeders, and go test drive the car and bed the new pads.