6.5 turbo diesel to 350 tbi swap i need help

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JScott23

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I'm doing this on a 94 6.5... check out my "1994 Chevrolet C3500 Build Thread"

May be some valuable information. As far as the TBI, might be easier to go to carb rather than TBI, but for what its worth I've covered a lot in my thread.
 

Big RED Burban

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thank you both that's a lot of help I know a carb might be easier but I tbi shouldn't be hard since we are swapping out the entire engine wiring harness for a 350 tbi harness one thing I love about these trucks is the harness just unbolts from the fire wall
hopefully when we are done this truck will look like it came factory with a 350 except for the intake wholes in the bumper which in my opinion is the perfect spot for fog lamps haha
 

Big RED Burban

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correct me if I'm wrong but I think the factory lift pump is inline and not in the tank if so could I just unplug it and put a regular gas pump in the tank or do yall think that we should swap out the fuel lines for factory gas fuel lines
 

JScott23

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I'm going to replace my lift pump with an inline fuel filter and then put a in tank fuel pump. Lift pump and fuel filters are roughly the same size/spec if I recall.
 

JScott23

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Mine was a diesel, so I'm going to end up putting a fuel filter where the lift pump was, and a TBI fuel pump/sender in the tank. Then I'm going to end up using the lift pump power wire to run the fuel pump in the tank. (That way it still runs off the OPS circuit)
 

Big RED Burban

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ok when you get to that point could you show me how you wire the pump up and are you running tbi or a carb if you are running tbi how are you going to modify the diesel fuel lines to fit into the back of the tbi
also do the diesels run return line to the tank? I haven't had a chance to look under my buddys truck lately
 

JScott23

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I'm going to run a carb. I'd like to run fuel injection, but i don't want to hack up the wiring harness.

Basically the 6.5 diesel fuel sender has two wires, a sender wire and a ground. The lift pump has a 2 wires, a power wire (looped in with the OPS circuit) and a ground.

The in tank TBI fuel pump has 3 wires... a power for the pump, sender wire, and a ground. By combining the two i'm thinking i should be able to run a stock in tank TBI fuel pump off the OPS circuit, then at the front use a regulator with a return, while keeping the 6.5 fuel lines. And the lift pump is about the same size as a regular fuel filter.

We'll see how it works on mine, the TBI fuel pump should send 9-12psi I think, carb needs about 5-10 psi I believe. As long as I keep the return line it should work fine.
 

JScott23

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I can't find a 92-93 6.5 diesel engine for less than $1500 so I ether have to do a cummins/LS swap or a carb swap. I went with the cheapest route.
 
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