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7.3 mod thread, Basic.

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I thought I would start a thread about modifying the 7.3. Most of us have modified our trucks to some degree, but for a newbie the thought of getting under the hood can be intimidating. I would like this thread to be about doing some basic mods that most of us have done and are considered to be fairly easy, easy enough for the "do-it-yourselfer" to tackle. Later we could do Engine mods, tranny, fuel, body or what ever you guy's want. These modifications may be different for the Superduty and OBS. Feel free to add to the list, once we have compiled our basic list then those of us who have actually done that mod can do a write up for the " How to 7.3 section ."

1. Air intakes.

The stock intake and filter are a good place to start the modification process of your 7.3. Better air flow than stock is a must for any level of mods you may plan for your truck. The Tymar air filter is the best bang for the buck and provides superior air filtration as well as air flow and can be used with very minor modifications to the intake system on both the Superduty and OBS. The AFE and the AIS are also superior systems that will provide the air filtration and flow at a higher price.

2. Exhaust.

Opening up the exhaust system is also a must for a better performing 7.3. You will see different terminology used.

a) Turbo back = Modifying your exhaust system starting at the turbo.

B) Cat Back = Modifying your exhaust system starting at the catalytic converter.

c) 3 ½" pipe = Stock system size from the turbo to the tail pipe.

d) 4" pipe = Size of exhaust pipe that can be used from the turbo to the tail pipe. e) 5" pipe = Size of exhaust pipe that can be used from the down pipe back to the tail pipe.

f) Down pipe = Section of exhaust system that starts at the rear of the turbo and goes down to start horizontal sections of the exhaust system.

g) Straight Pipe = No Catalytic converter, no muffler.

h) Muffler delete = Removing the muffler and installing a piece of pipe in it's place.

The less restrictions you have in the exhaust system will help lower exhaust gas temperature ( EGT's ). 4" systems seem to be the most popular for our trucks. 5" systems for the more modified trucks. Adding a free flowing exhaust can lower your EGT's by 150/200 degrees.

3. Gauges

Having gauges is a must to monitor your trucks performance. You can choose from two different types, analog or digital. Digital are viewed on a screen usually placed on the dash. Analog gauges are placed in a "pod" and can be located just about anywhere. There are three gauges that are considered must have.

a) Pyrometer, used to measure EGT

B) Boost

c) Transmission temp

4. Crank Case Venting

Crank case gases are currently vented through a tube into the air intake leading to the turbo. This leads to the oily film you see in your air intake and on your boots and in the intercooler. Replacing the CCV tube with a straight walled pipe will also increase the cold air intake by about 20 %.

5. Foil delete.

The removal of the insulation and foil on the drivers side intercooler tube. No added performance but will allow you to hear the turbo better and do some painting.

6. Transmission Cooler.

The transmission cooler on the 7.3 is not real big, adding a 6.0 or other type of aftermarket cooler will keep the transmission temps down and add longevity to the tranny.

7. 6.0 Intercooler.

The 6.0 intercooler is about 30% larger then a 7.3 intercooler. Will help reduce EGT’s.

8. Overboost.

Our 7.3's are set to start defueling when our trucks pcm get a reading of around 18-24 lbs of boost. To prevent this you can install a Boost fooler or Overboost annihilator. This will usually stop the ses light.

9. High pressure oil cross over line.

The high pressure crossover (HPX) line connects the driver side and passenger side high pressure oil rails together. The result is a more balanced high pressure oil system with fewer pressure spikes. In most trucks this will smooth operation and may even quiet the engine somewhat.

10.Tuners and Chips.

Are manufactured by variety of companies and are easily installed. Chips and Tuners are also where everyone usually wants to start the modification process on their truck. If you are going to put a chip or tuner in your truck it should be done after you have installed at the very least your gauges.

For a glossary of terms that are frequently used with our trucks click here! http://www.forddoctorsdts.com/glossary/

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I suggest checking the Fuel Pressure Regulator (FPR) for proper fuel pressure. If low, add a BB to bring pressure up to normal. This is also known as the "FPR Shim" mod.

Once fuel pressure is verified, it's time for the ICP Resistance mod. If you have a tuner or chip, this mod is not needed. With this mod, we add a few dollars of Radio Shack parts to trick the PCM into thinking the HPOP pressure is low. This is the "Poor Man's Chip/Tuner" mod. I have it on my '97 and the dyno sheets prove the results.

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Instead of an overboost eliminator you can get a hardware store pressure regulator, set it to 20psi with a compressor and put it inline on the MAP feed. Another thing when it comes to the wastegate, I've heard two ways, unplug the electrical connector in front of the X, or unplug the actual wastegate line. On my buddies 99 we tried the electrical connector first. Went from 17 psi to 14 psi. Plug that back in and pull the red wastegate tube, say hello to 22 psi. Keep in mind this is a bone stock truck, just gauges

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