Carb to TBI

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usar17

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Chip?

So what all do i need to buy? Gasket Set, .....?
 

Jims86

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Chip?

So what all do i need to buy? Gasket Set, .....?

Only if you want the ECM to control lock up, will you need a different chip. Not if you retain the Vac switch.
You can get a full gasket kit from summit....even comes with new valve stem seals. Then of course, the aluminum fuel line for the return, and some SAE J30R9 fuel injection line, and Inline pump, unless you swap tanks too.
 

usar17

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Ill stick with vacuum then to keep it cheaper. Any suggestions on pumps? And is that just wired up for ignition hot. Ive swapped a tank once....don't feel up to doing that again.
 

usar17

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after thinking about it more...

I'm guessing the fuel pump is wired through the harness not straight to a hot.

And is there a way to test the current 87 fuel pump/sending unit? The bed is off the truck so i can easily remove it.

I started labeling and disconnecting the wiring harness today. So far not bad.
 

Jims86

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after thinking about it more...

I'm guessing the fuel pump is wired through the harness not straight to a hot.

And is there a way to test the current 87 fuel pump/sending unit? The bed is off the truck so i can easily remove it.

I started labeling and disconnecting the wiring harness today. So far not bad.

I would go ahead and swap 87 tank over with the pump, because it is baffled so the fuel pump does not suck air on corners when the level is low. No baffles in the 85 tank.
 

usar17

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Can I jump a little 12v power to a lead to test it?
 

Jims86

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Can I jump a little 12v power to a lead to test it?

Yup....there should be a red and white wire at the fuel pump relay on the firewall with a pigtail. Jump 12v to that, andnit should activate the pump.
 

usar17

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I hate to be a pain. But which relay is the pump relay? Can I just unplug the harness at the tank and run 12v to one of those pin? Im not referring directly to the sending unit pin, but the 6" long harness attached to the sending unit


Like I said, bed is off it so I can easily just hit the harness at the sending unit. Just need to know which wire is for the pump and which is for the fuel gauge
 
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Jims86

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I hate to be a pain. But which relay is the pump relay? Can I just unplug the harness at the tank and run 12v to one of those pin? Im not referring directly to the sending unit pin, but the 6" long harness attached to the sending unit


Like I said, bed is off it so I can easily just hit the harness at the sending unit. Just need to know which wire is for the pump and which is for the fuel gauge

Yep....its the tan wire with the white stripe.
 

usar17

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Hmmmm....lol can u try again.
 

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foamypirate

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Hmmmm....lol can u try again.

At the sending unit, pink is for the fuel gauge, brown or gray are for the pump (depending on which side you are looking at). The tan/white stripe Jim is talking about goes from the FP relay to the switching valve, if I remember correctly.
 

Jims86

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yeah... foamy is right, i didnt know it was dual tank. The red and white wire at the relay is for pump testing.
 
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usar17

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Well I spent the day pulling wires out of the donor.....what fun that was :/

I left the ecm to engine wires connected for now.

So currently spread across my work bench is all the interior wiring. I started at the ecm wiring harness where it had a 6 pin connector just off the ecm itself. I pulled from there all the way to the instrument cluster then to the fuse block. So I have allllll the wiring. I've got all the tape off now. Is there any write up or info on what I can cut and what I need?

So far my tracing has show me that it goes from the ecm to the vss modular, instrument cluster, obd1 connection, ecm1 fuse, and an orange/black black/white connection at the steering column.
 

Jims86

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Well I spent the day pulling wires out of the donor.....what fun that was :/

I left the ecm to engine wires connected for now.

So currently spread across my work bench is all the interior wiring. I started at the ecm wiring harness where it had a 6 pin connector just off the ecm itself. I pulled from there all the way to the instrument cluster then to the fuse block. So I have allllll the wiring. I've got all the tape off now. Is there any write up or info on what I can cut and what I need?

So far my tracing has show me that it goes from the ecm to the vss modular, instrument cluster, obd1 connection, ecm1 fuse, and an orange/black black/white connection at the steering column.
All you need is the harness from the ecm and the engine...dont need the interior wiring.
 

usar17

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not the 6 wires that go from the ECM to behind the Cluster?

ECM->VSS,ALDL, Fuse Block, Inst Cluster, Transmission Position Sensor
 

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