How-To: Install Longtube Headers 1999-2004 SVT Lightning

[Darren5.0L]

How-To: Install Longtube Headers 1999-2004 SVT Lightning

By Darren5.0L

Performance and Sound:
Two very good reasons why any Lightning or HD owner might consider pulling the factory manifolds to swap in a set of longtube headers. For my 2003 Lightning it was both, and the sneaking suspicion that one or more of my catalytic converters had plugged up on me.

Having done four longtube header installs on various vehicles, I’ll say this truck has been the easiest of them all. With the help of a second person, and simple shop tools, this install was completed in about 8-10 hours. I would rate this install somewhere in the moderate difficulty level depending on personal skill level, but really it’s dead simple.

SAFETY:

First, DISCONNECT THE BATTERY! I cannot stress this enough; you will be working near the starter and solenoid with large bits of metal. The chance of electrical shock or engaging the starter is nearly absolute.

Secondly, ensure you have a safe working environment, with any safety equipment you deem necessary, should you not feel confident consider consulting a professional.


TOOLS:
At minimum you will require a good selection of metric sockets and wrenches, with various extensions. A 1-¼” open end or adjustable wrench is required for the lower EGR fitting. A jack, stands, level work surface, and a second vehicle should also be considered mandatory.

Gear Wrenches-
These things are worth their weight in gold, not just for this project, but any installs under the hood. I recommend grabbing a set.

Spare Set of Hands-
Not exactly a tool, depending on who you get to help, but a second person will make life much easier on this install.

PARTS:
Here your individual header kit will vary in what is required versus what is supplied, for example I purchased OBX Longtube Headers and Catless Midpipes.

OBX Provides:

#1 OBX Header – Driver Side
#2 OBX Header – Passenger Side

#3 Resonated Cat Delete – Driver Side
#4 Resonated Cat Delete – Passenger Side

#5 Midpipe - “S-Shaped” Driver Side
#6 Midpipe – “Straight” Passenger Side

#7 Collector Studs & Nuts – X6 (not shown)
#8 Tapered Band Clamps 2.5” – X2 (Garbage, shown attached to Cat Deletes)

#9 Donut Gasket 2.5” – X2 (not shown)
#10 Exhaust Manifold Gasket – X2 (Garbage, not shown)

Warranty Sheet – X1 (Warranty?)

To complete my install I used the following additional parts:

Stage 8 Locking Header Bolts PN (Optional)
EGR Delete Kit (Optional)
4 X O2 Bung Plugs (pipes feature 6 bungs)
BBK O2 Sensor Extension Harness Kit
Motorcraft 5.4L 2VManifold Gaskets X4
Walker Lap Joint 2.5”/2.75" Stainless Band Clamps.

Install Part I – The Headers:

Step 1
-Disconnect Battery.

Step 2
-Remove hubcaps and break torque on wheel nuts.

Step 3
-Ensure vehicle is in Park, set Park Brake, and chock rear wheels
-Raise Vehicle and rest securely on jack stands.
You will require enough elevation to access and/or remove all portions of the exhaust, and the headers are installed from the bottom, ensure you give yourself enough working space.
-Remove wheels.

Step 4
-Remove Left and Right Inner Fenders.

There should be 3X 7/32 bolts (white arrows) in the wheel arch, and 5X “Xmas Tree” plugs that retain the liner. Be careful as there are two connectors on the engine side of the liner which retain the ABS sensor and or harnesses. These connectors may be easily accessed once the liner drops away from the fender.

Driver Side

Step 5
-Disconnect EGR Fitting from Manifold
-(Optional) Install EGR delete kit, and fit cap to driver side header.

Step 6
-Disconnect O2 sensor harnesses
-Remove Driver Side Midpipe (I used a sawzall)
-Disconnect Block Heater if applicable

Passenger side Midpipe pictured:

Step 7
-Working from the fender well, Remove Driver Side Manifold
This is sometimes easier said than done, soaking nut & stud assemblies in penetrating oil may be required. If a stud remains in the block, a 5mm socket can be used to remove it. If a stud breaks off in the block, Stop, assess the situation, and then use a sensible method to extract the offending piece.

For the following sequence of illustrations, Passenger side shown, Driver's side similar:

Step 8
-Install Front Oxygen Sensor extension harness.
-Clean cylinder head gasket surface and chase manifold bolt holes.
A dedicated tap is not necessary for this step, but if using new bolts, apply a dab of anti-seize and run them completely in and out of each hole. This process is much easier than fighting with bolts while installing the header and will make them thread in with less effort.

Step 9
-(Optional) Remove oil dipstick and tube, required for OBX Headers
-Install manifold gaskets and 4X lower manifold bolts leaving at least ¾” of the threads exposed.

Step 10
-Install Driver side header by passing up from the bottom and “hang” the flange from the 4x lower bolts you installed in Step 9.
-Employ second person at this time.

Step 11
-Ensure gaskets are properly aligned and install 4X top bolts.
-Evenly tighten all bolts until snug
-Torque Header Bolts to specification
-(Optional) Install Locking tabs and C-clips on Stage 8 Fasteners

Step 12
-Reinstall Oil Dipstick
-Reinstall EGR Tube (if reused)
-Reconnect Block Heater if applicable
-Inspect for any fitment issues.

You have now completed the driver side header, the passenger side will be slightly more difficult as the starter does take up some space, but it is still fairly easy.

Step 13
-Disconnect O2 sensor harnesses
-Remove Passenger Side Midpipe

Step 14
-Disconnect Starter Wires if required
-Unbolt, but do not remove Transmission Dipstick and Tube

Step 15
-Working from the fender well, Remove Passenger Side Manifold
-Refer to Step 7 above for more info

Step 16
-Install Front Oxygen Sensor extension harness.
-Clean cylinder head gasket surface and chase manifold bolt holes.

Step 17
-Install manifold gaskets and 4X lower manifold bolts leaving at least ¾” of the threads exposed.

Step 18
-Install Passenger side header by passing up from the bottom and “hang” the flange from the 4x lower bolts you installed in Step 17.
-Employ second person at this time.
This header will be a little more difficult, as there are more obstructions in the way. Take your time and the header should fit in very easily. Bending or Removal of some heat shields may be required.

Step 19
-Ensure gaskets are properly aligned and install 4X top bolts.
-Evenly tighten all bolts until snug.
Some bending of the transmission dipstick tube may be required to run up over the number 4 primary, be careful not to damage anything during this process.
-Bolt transmission dipstick tube back into factory location.
-Torque Header Bolts to specification
-(Optional) Install Locking tabs and C-clips on Stage 8 Fasteners

Step 20
-Reconnect Starter wires if required
-Inspect for any fitment issues.
On this side the OBX’s fit somewhat close to the frame, I removed one small heat shield to obtain a little more clearance, but flattening of one primary may be required.
-Install and connect both front O2 sensors to the BBK harnesses.

You have now installed both longtube headers.

 

[Darren5.0L]

Install Part II – The Exhaust

This portion is very easy in description but depending on each person’s specific setup, it may be frustrating and time consuming. A second person will help with aligning the various exhaust parts, while providing support during tightening. If you are alone, (not recommended) jack stands and patience make suitable replacements.

As with installing any exhaust, the best approach is do a "rough" install using stands to set everything in place, and then being to tighten everything up progressively. I prefer to work front to back, but there is no surefire way to do it, simply adjust, tighten, and inspect for clearance issues, then repeat.

A note about the OBX mid pipe and resonators;

Six O2 bungs?
My kit came with 6 bungs, ideal for someone who wants to run cats and dual wide band sensors. For me this is where those extra plugs were used, I ran the factory narrow band sensor in the first bung on each bank, then simply plugged the remainder. A dab of anti seize paste will aid removal if you ever want to run a wide band.

These are designed to have the mid pipe portion fit inside the the slightly over sized resonator exit, hence the lap joint. My particular resonators were a little too tight to slide the mid-pipe easily so I faced two solutions, use a tailpipe expander to try to make the resonator larger, or trim about an inch from the mid-pipe and use the band clamp for the union.

I elected the 2nd choice and carefully removed small lengths of mid-pipe until both sides fit properly, this process can be frustrating, and a good set of sawzall blades are mandatory. The stainless used by OBX is quite hard, and destroyed a Dewalt demolition blade when it quickly overheated, use oil to cool the blade and keep the speed down.

Once the exhaust is properly fitted, now is a good time to recheck the park brake, start the engine and begin looking for leaks. Carefully check each fitting, joint, and flange, if you having a difficult time finding a particular leak, feeding the engine a bit of seafoam can help locate the source.

Once everything is leak free, time to re-assemble the truck. Ensure all wiring harnesses are connected and that the engine oil and transmission dipstick tubes are firmly attached. Finally replace the fender liners, mount wheels, remove truck from stands and torque lugnuts.

If everything goes well, you'll be rewarded with that extra power and distinctive tone that only longtube headers provide.

[ame="http://www.youtube.com/watch?v=9nIozDzZ_pI"]YouTube- SVT Lightning Thunders through a Tunnel.mp4[/ame]

Observations:

The Catback - When running a catless system such as this, I typically choose a quieter muffler, in this case the Borla catback. At idle it has a good tone, WOT is awesome and no drone a cruise, the perfect balance for a daily driver. If you want something a little wilder, there are many louder offerings from the "usual suspects" at Bassani, Magnaflow, and so on.

Tuning - I did get a custom tune after the install at recommendation of my tuner, but I did drive for nearly 3 weeks before hand untuned. I didn't do any WOT runs or Boost during that period and made out just fine, I recommend getting a look at your WOT A/F ratio for safety. 1 CEL reported, which brings me nicely to my next point.

Cat Deletes and OBD II - It turns out that the newer revisions of the Diablosport Predator do not allow you to turn off the rear O2 sensors as an end user. It may appear that you can in the menus, but you will trip a CEL after a few start/shutoff cycles, this was quickly cured buy a email "tune" from my dyno tuner.

I do not have before and after performance numbers, but I do have a video of the dyno run from my tuning session:

[ame="http://www.youtube.com/watch?v=loXRgbrS2rM"]YouTube- Guess the Horsepower[/ame]

Dyno Sheet from a very stingy MD600

Overall, I was rather impressed with both the fitment of the Chinese made OBX headers and the ease of working on the Lightning’s exhaust system. Anyone who has experience working on a Modular powered SN95 Mustang (like me) should find themselves very annoyed at how friendly a Lightning is to work on. Working inside the fender well on a mechanic’s stool is nearly as easy as working at a bench.

If you have any comments, corrections, or omissions to bring to my attention please feel free to PM or Email.
Thank you for Reading,

Darren (5.0L) Lynch