You are on the right track, Intake needs to go, the factory one is horrible and doesn't filter properly, and at 330,000 miles on stock air intake I would be surprised to see what your compressor wheel in your turbo looks like. After 210,000 on the stock one mine was pretty beat up.
You can do a DIY air filter that a lot of people do, you buy a napa filter #6637 and clamp that onto the end, very good filter...have nothing but good to day about it.
Second is going to be your exhaust, specifically your down pipe, the factory down pipe(short piece going from turbo to under the truck) is flat, and very restrictive, you will have to bend the firewall in a bit to fit a 3" downpipe in there, but its not as bad as it sounds. After that I recommend a straight pipe, all of these exhaust company offer mufflers to go with there systems, but they litterly do nothing, dont make the truck any quieter and just add restriction and backpressure for no reason I can see. Now that you can put more air through your engine, and let more exhaust out you need to do exactly that.
Next you will want to look into gauges, specifically one, Exhaust temperature. You probably know what it is, but just incase.....its exactly what it says, the temperature of your exhaust lol, you put a probe in right at your manifold and its the CLOSEST way you can tell the temperatures of your pistons and valves. You will need this because when you start to add fuel to the fire, temps go up, they go up to much and bad things happen, they go up and you let off the throttle everything is fine.
There are TONS of other gauges that you will eventually get(this stuff gets addicting) boost, tranny temp, boost, fuel pressure ect. all very important to know when far above stock power levels.
Now that you can see how hot your engine is, you need a tuner, it plugs into the Computer and just tells the computer to give it more fuel, allow more boost ect, also if you have an AUTO it will control shift times i think. I reccomend a 6 position adjustable tuner...because you can have 6 different power levels at the turn of a switch.
There are tons of options you will need to look into.
After that if you want to go further then you can do exactly that, get into injectors, HPOP's, electric fuel systems and much much more...hell if you want to you can drop 16,000$ into a mechanical injectors p-pump kit and make upwards of 2,000 ft lbs of torque....some you have to figure out what you want to do and go for it.
you will love the truck!
1997 F250 7.3 5 speed, 3.55s, D60, 4" Diamond Eye Exhaust, Napa Intake Filter, E-Fuel, 35" bfg mt's, stage 2 rosewoods/tuning, Gauges
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