LS Swap Fuel Pump
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Bextreme04
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The factory in-tank pump from a GMT 400 fits right into a TBI fuel sending unit and gives the correct pressure and fuel flow. I'm using the one from my 97 K2500 Suburban donor truck. Its an AC Delco EP381 https://www.rockauto.com/en/moreinf...xjH0rgDjLPy4AUXbbsybBd0/HSdZtYJWaOny9kkhlrD6o.
Depending on the year 5.3 it will be either a return line system where the fuel pressure regulator is integrated into the fuel rail or a returnless system. You either don't need to do anything else and just plumb the return line back to the tank from the engine in the case of a return line system, or you can run an in-line corvette filter/regulator if your 5.3 is a returnless system. Its a common enough thing that summit sells the filter and AN adapters together. https://www.summitracing.com/parts/cmb-03-0263?rrec=true
My MPFI 454 is notorious for failed fuel pressure regulators and it is buried under the intake manifold at the back of the engine, so I'm blocking off the regulator and return line on mine and using the corvette filter/regulator in-line mounted to the frame rail instead. Even if it fails as much as the factory regulator, it is quicker and easier to replace as well as cheaper than the stock L29 regulator.
Depending on the year 5.3 it will be either a return line system where the fuel pressure regulator is integrated into the fuel rail or a returnless system. You either don't need to do anything else and just plumb the return line back to the tank from the engine in the case of a return line system, or you can run an in-line corvette filter/regulator if your 5.3 is a returnless system. Its a common enough thing that summit sells the filter and AN adapters together. https://www.summitracing.com/parts/cmb-03-0263?rrec=true
My MPFI 454 is notorious for failed fuel pressure regulators and it is buried under the intake manifold at the back of the engine, so I'm blocking off the regulator and return line on mine and using the corvette filter/regulator in-line mounted to the frame rail instead. Even if it fails as much as the factory regulator, it is quicker and easier to replace as well as cheaper than the stock L29 regulator.
custodian
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I'll be using an 02 5.3 from a truck. Picking it up Saturday. I'll be putting this in the 73 C10 2wd I gave my oldest granddaughter due to the transmission is on it's way out, so I'm taking the 283 out I built for it and replacing with the 5.3 and hopefully a 700R4.
Bextreme04
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If that's the case, I'd get the harness, computer, engine and trans all from the same truck. 4L60e is a newer 700R4 and will be more reliable and work with the OS already on the computer. Going to a 700R4 just removes the electronic controls and makes more work for you to try and figure out how to get the TVS cable hooked up to a 5.3. You can probably get the fuel pump from the donor truck also.
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Rather than go through and have to convert the 4L60E to a mechanical speedometer drive, I'll just use the 700R4, and If I can't find a 700 I'll use the TH350 I have sitting in the building.
I'll change the gas tank to one with a baffle and check into the fuel pump you mentioned.
Bextreme04
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I would just change the speedometer or the whole cluster to a 90-91 Suburban cluster with the electric speedometer. Then you don't have to convert anything.
I think you are underestimating the difficulty in combining the old and new. Either the 700 or TH350 will need a kickdown cable, that doesn't have anywhere to hook up. Also the ECU needs a VSS input for drive-ability and idle in gear which you won't have with an old transmission running a mechanical speedo cable without running one of those junky adapter unit things. I got a whole 91 gauge cluster for $60 locally. You would only need to run a single wire from the ECU to the gauge cluster connecter and change the pin locations. There are a few writeups on here that cover it in detail.
It also makes it much easier to do the whole swap to get the whole thing as one. Having a different trans will also require you to reprogram the ECU, which is not cheap unless you know how to use the opensource programs.
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used the EP381 on mine. Bolted right to the ~88 burb tank sender. I went ahead and did the fuel tank relocation under the bed in prep for the swap. Switched from side to the rear tank during the swap. One less headache to deal with under pressure due to it being a daily driver.
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The 5.3 is an 02 cable driven model, so no problems there. As for the ECM, I'm taking it to a guy who has been swapping the LS into 67-72 C10's with 350 turbo trans.
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k. You can get a 'burb tank for less than $20 difference on amazon. Amazon has the best shipping, sorry RockAuto, but use RA to get the part number of the tank you want, then find it on Amazon prime with free shipping which ever way you decide to go.
Blackbeard44
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I use a walborro 550 mounted on my frame,corvette fuel filter has built in regulator, I am able to still use both tanks with no problems, I have been driving my LS swapped truck for 3 years now and it is dependable, I am going to look into putting pumps on the hangers in the tanks, I just have to come up with a way to switch the return into what ever tank I am using
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Blackbeard44
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I have wondered what I would take to hang pumps into both tanks and use the switch to turn up whatever tank you wanted, but what about switching the return? anyone have dual tanks with dual pumps? that is my goal this summer to get a pump in both tanks and get it working
Bextreme04
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The factory TBI dual tank setup does exactly that. 87 single cab truck with dual tanks would have that system from the factory. 87-91 CC with dual tanks would also.
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