I believe you are getting in WAY over your head here. Unless you have forged internals in this engine, and I do not believe that you do currently, you will see all sorts of problems. Not to mention the fact that nobody is Turbo-ing this engine with any regularity. You will need to be the pioneer in this project of turbo charging an engine that nobody else IS…you have pockets that deep? Is it that important to you? You could Turbo Charge an LS Chevy all day long and many are out there right now and so are the parts and so is the knowledge etc… so its more readily available.
If you want to easily force feed this engine a Paxton Supercharger would be easier than a Turbo for this particular application…even then all the same issues present if there is no kit or programming to handle the boost.
Go with a known platform and setup if you want turbo power, Turbo Diesels exist for this very reason. If you are going with gasoline its best to start with a stock turbo vehicle to begin with like one of the many Ford F150 V6 Twin Turbo Eco Boost engines…they are ready to go and can handle a lot of boost.
You are in for an unimaginable nightmare of problems if you move forward with your vehicle and this idea for so many reasons. It be a much better experience for you to tune and play with an already turbo charged vehicle…the turbo is the part that gets top billing…there is a ton of other stuff the engine needs to make boost work for you…I wont list them all.
If you’re not using a stock engine that changes things, some.
Did you also upgrade the heads, cam shaft, crank shaft, and rods? Did you upgrade the brakes and suspension? What’s the top weight rating of your hitch?
There are so many other components in play other than the ones you’ve mentioned. The cam shaft, crank shaft, and connecting rods were designed for a naturally aspirated engine, so adding a turbo will likely shorten the engine’s life anywhere where metal meets metal.
Doesn’t mean anything if the transmission is only rated to 300-340 ft/lb of torque
Doesn’t mean anything if the internals are still cast (which the crank and pistons are, the rods are powder forged cracked, which isn’t the same as forged steel) . This engine was not set up for boost. When someone “bulletproofs” a Ford 6.0L for example, you’re correcting the design flaws in an engine was designed with forced induction in mind. If you add boost to this engine, an engine was not designed with forced induction as a design criteria, you’re going to run into problems, even with your super-duper head studs.
If you’re trying to pull a 13k-16k trailer with this thing, you’re making a horrible personal decision. If the total load (truck + trailer) is 13k-16k, then you’re still over the stated limit (4500 lbs if 4WD, 5800 lbs if 2WD) by a significant margin. In either case you’re well over the stated maximum towing capacity, so of course it’s going to be slow. That shouldn’t be a shocking development.
You just don’t have necessary truck to pull the kind of loads you want to tow. The most reasonable course of action would be to sell this thing and get a truck that’s better suited for what you intend to do. If you’re towing a 13k-16k pound trailer regularly , then a 3/4 ton or 1 ton diesel is what you’re going to want. If the trailer is closer to 7k-9k, then you can get away with a half ton with the top engine option.
Just to put it out there, if you tow 16,000 pounds in a vehicle rated to tow 5400, and you run into someone and hurt them, the lawsuit will ruin you. This is a bad idea. Get a truck that’s suited to its mission.