Tbi conversion help

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yevgenievich

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I have a wiring harness for the 747 as well if you want to try that route. Will pm
 

Tonyorlo

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I like that much better than trying to mess with burning proms and sourcing the correct ecu. Should the ignition and everything else plug into the current engines components?
 

1987 GMC Jimmy

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I like that much better than trying to mess with burning proms and sourcing the correct ecu. Should the ignition and everything else plug into the current engines components?

I like that idea better, too. Everything's gonna be the same, I think. I doubt you'd have the round style TPS sensor so that should be okay. The 7747 is a much better option. If the ESC ever fails, you don't have to replace the whole computer, it's easy to tune, and there's a lot of support out there. Plus, if you want, you can make your own ALDL to USB cable and do system checks, data logging, and tuning. I hope it works out. Here's a great thread by @Georgeb. Inspired me to do the same thing. http://www.gmsquarebody.com/forum/showthread.php?t=13194
 
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Tonyorlo

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Viktor is going to hook me up with a harness and ecu. I'll check everything out on the stand before I drop the engine in. The engine has sat for 10+ years in a garage. I will pull the valve covers and oil pan just to check it out. I considered buying a throttle body, viktor recommended I freshen the one I have up so I will definetly do that.

I really like the idea of being able to data log and make adjustments myself too. I would like to maybe throw a set of headers on the engine someday. Being that I won't have catalytic converters will that throw a code?
 

1987 GMC Jimmy

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Viktor is going to hook me up with a harness and ecu. I'll check everything out on the stand before I drop the engine in. The engine has sat for 10+ years in a garage. I will pull the valve covers and oil pan just to check it out. I considered buying a throttle body, viktor recommended I freshen the one I have up so I will definetly do that.

I really like the idea of being able to data log and make adjustments myself too. I would like to maybe throw a set of headers on the engine someday. Being that I won't have catalytic converters will that throw a code?

Nope. The O2 sensor is pre-cat.
 

yevgenievich

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Viktor is going to hook me up with a harness and ecu. I'll check everything out on the stand before I drop the engine in. The engine has sat for 10+ years in a garage. I will pull the valve covers and oil pan just to check it out. I considered buying a throttle body, viktor recommended I freshen the one I have up so I will definetly do that.

I really like the idea of being able to data log and make adjustments myself too. I would like to maybe throw a set of headers on the engine someday. Being that I won't have catalytic converters will that throw a code?

Sitting for so long, also test the injectors. Soak them for some time, then can comnect one pin to 12 v and tap ground wire on the other pin. Should hear a click. But do not hold power applied, just tap very quickly. If no click, tap on inject with a screwdriver handle or the like and try again.
 

Tonyorlo

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Ok, I haven't priced out injectors, are they expensive? I'm going to use a inline fuel pump for now, when I switch to in tank pumps is there a factory switch option for the dual tanks?
 

yevgenievich

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All parts from 87 trucks with dual tanks will swap over. Injector prices vary, yours might be good after cleaning.(new/rebuilt $80-$150 range) you might consider getting one tank replaced with 87 one and run intank fuel pump from the start. Then later get the other one switched over.
 

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If you want to do like an ultrasonic type cleaning, WitchHunter performance does that and flow tests them for $22 a pop. It's a gamble, but it'd be a little less than half of what you'd pay for new ones. I've never used them, but I know folks on here have.
 

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I think for now I will take the gamble with the injector. That is above option rather than buying a new one if I honk it's just clogged.

Can I drop a later sending unit in the early tank?
 

yevgenievich

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I think for now I will take the gamble with the injector. That is above option rather than buying a new one if I honk it's just clogged.

Can I drop a later sending unit in the early tank?

Better to swap tanks because efi tank has a baffle, while ofiginal carb tank does not.
 

Tonyorlo

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Ok. Well I really have no use for 2 tanks, so I will most likely eliminate a tank when I do this. A quick glance at rockauto looks like I will have about $120-$150 in a new tank, sending unit, and pump.
 

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Ok. Well I really have no use for 2 tanks, so I will most likely eliminate a tank when I do this. A quick glance at rockauto looks like I will have about $120-$150 in a new tank, sending unit, and pump.

I would recommend you look around for a pump that can withstand higher PSI, I put a stock replacement in mine and now to increase the HP I need higher pressure pump.
 

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Will you need to run a regulator with a aftermarket pump?
 

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