79 5.0 Exhaust

[orrcapri]

I recently looked into doing some work with my 79 Capri and heard that there may be some trouble while doing the exhaust due to body style. What are the exact issues and how can they be avoided? Does the exhaust job have to be customized? Thanks!

[tjgtstang]

I recently looked into doing some work with my 79 Capri and heard that there may be some trouble while doing the exhaust due to body style. What are the exact issues and how can they be avoided? Does the exhaust job have to be customized? Thanks!

Only thing I can think of would be the transmission crossmember. 79 is a single hump, your going to need a 86,87-93 5 liter double hump crossmember other than that and a passenager side tailpipe and muffler hangers thats it. I could have forgotten something.

[JACook]

The biggest issue if you want to install a passenger side tailpipe, is the brake hose to the
rear axle needs to be relocated to where Ford put it in '85. Some guys try to sneak the
passenger side tailpipe past the hose in the stock location, but this is not a good idea.
It's not hard to extend the line over to the center location, and add the bracket for the
body end of the hose.

[MAD MIKE]

As mentioned the single to double hump trans crossmember, rear brake line/hose, and verify where your plastic EVAP line from the gas tank is run.

[4eyex2]

The exhaust shop ran the passenger tail, never had an issue, but line was definitely too close for comfort. I'll be using 85+ routing when I resurrect the vert

[tjgtstang]

The biggest issue if you want to install a passenger side tailpipe, is the brake hose to the
rear axle needs to be relocated to where Ford put it in '85. Some guys try to sneak the
passenger side tailpipe past the hose in the stock location, but this is not a good idea.
It's not hard to extend the line over to the center location, and add the bracket for the
body end of the hose.

Thanks for the info, I help a freind do a 351w swap to his 81 cobra but we didn't use any tailpipes just some dumps. We also didn't mark VII rearend swap too.

[79Coupe]

Listen to JACook. In addition, make sure you get the tail pipe hangers for the rear of the car. Might be able to use the one you have now for the single, but I just bought new hangers for an 87 - 93 LX 5.0

[Curtis]

Not sure but I have read that the mount for the double hump x memeber will need modified. Maybe someone can chime in and confirm.

[toaster]

If the mounts are narrow you have to shorten the ends on the crossmember. I had to on my 79. Not that hard to do

I would not mess with the brackets on the bottom of the car. Just modify the double hump crossmember as follows:

1. Remove the 4 rubber bushings from both ends of the outer mounting tubes.

2. On each side there is an 'inner' steel tube that mounts inside and is supported by each bushing. Remove the inner tubes (2) from the bushings. (They may be rusty and you may want to clean them up a bit with a whire wheel, etc)

3. Using a fine tooth hacksaw cut the outer mounting tubes off flush with the sides of the crossmember stamping.

4. Re-install the 4 rubber bushings leaving the inner tubes out for now.

5. With the outer tubes cut off flush and the bushings re-installed measure the distance across the modified crossmember from the outside of one bushing to the outside of the opposite bushing - note this dimension - it should be the same as the distance between the brackets on the bottom of your car (2.75 inches).

6. Cut the inner tubes to this length, remove the bushings and install the inner tubes and bushings in the outer tubes.

If you are concerned about cutting too much, etc, you can take some measurements first:

1. The distance between the brackets on the bottom of your car should be 2.75 (2-3/4) inches.

2. The width of the crossmember without the extending tubes (as if cut off flush) on each side should be 2.25 (2-1/4) inches (measure before cutting).

3. The length of the rubber bushing extending beyond the tube on each side should be .25 (1/4) inch.

4. The modified crossmember would then be 2.25 +.25 + .25 = 2.75 wide., same as mounting brackets.

Ford changed the undercar mounting bracket dimension on Fox Mustangs from 2.75 to 4.50 inches starting in 1982, so 1982 and later Mustangs do not require any mods to the car or double hump unit to install it.

According to FMS catalog:
Fox cars with 2.75 brackets:
78-81 F/Z
79-81 Mustang
81-82 G/C

Fox cars with 4.50 brackets:
82 -83 F/Z
82-up Mustang
83 - up L/M
80-88 T-Bird

Good luck,
Paul

Please click here to check out my 78 Zephyr at my crappy Cardomain webpage

[JACook]

That trick works fine as long as you're not using an AOD. The reason the mounts were
widened starting in '82, was because the AOD trans mount sits farther back than on the
other available transmissions.