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You've likely got an electrical fault bleeding the battery. You need to locate where that is happening. Likely suspect would be a fault in the alternator which wouldn't show up by removing fuses. Another possible would be the injection pump solenoid. If not wired correctly that unit can drain the battery. Those are the two most likely suspects. That current draw is pretty severe to bleed the battery so fast. One problem I see on that build is there's no intercooler. A stock P pumped 4bt always had one and if this one has been turned up any at all you're fighting against heat to make power. With any kind of boost level at all from the turbo, the compressed air can reach 300 deg F or more. Hot air makes poor power. Also, looks like that engine has a.n H1C turbo which is not what a P pump used. It should have an HX30W. The lack of an air cleaner system is a death notice for the turbo plus you're sucking hot air off the exhaust manifold. Here's a photo of what that engine should have looked like on the turbo side on an original install.
 

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Dreamin, you need to find a way to lower your RPM's. You have more HP at the higher RPM but far less torque. Need cruising RPM in the 1700-2000 range. Sometimes things just can't be what we want.
 

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To check the electrical draw you need a meter that reads current flow. If you start unhooking things and it still shows a current draw, the alternator would be a prime suspect. If you disconnect it's charge wire from the system and the current draw stops then you've found it. If that doesn't stop it then it's got to be a source not controlled by the fuse block if you've remove it from the current circuit. Instead of disconnecting the fuse block, you'd want to remove individual fuses and see if the draw stops. If not, replace that fuse and try another one. Electrical bugs can test ones sanity some times. The old H1C turbo won't hurt anything but it's not the best performer. Cold air side of that turbo should be 3" unless someone stuck a Dodge H1C on there which would be 4". Hope they didn't do that because that is a terrible turbo for a 4bt. Be nice if the guy can tell you the model of the turbo. Don't think it's a WH1C or HX35W but can really see it with all those hoses in the way. If the turbo is the one I think, the EGT's shouldn't be much of an issue. Those turbos had a huge turbine housing to help get rid of excess heat.
 

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Actually, Cummins recommends the pyro probe to be after the turbo. The reason for that is that if the probe should break it won't damage the turbine wheel. That in itself would be a very rare occurrence. Post turbo is fine but you have to keep in mind that reading will be 200-300 deg lower than pre turbo. I'd think 1000 deg post turbo would be the limit. Most guy shoot for 1000-1100 deg pre turbo. Another rule that many don't follow is when you come to a stopping point, don't just shut down the engine. You need to let it idle until that temp drops to around 500 deg or a bit lower. You see those big rigs sitting at the truck stop with engines idling is not to just waste fuel. They are saving their turbo from damage.
 
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