HEI swap

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Schurkey

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If you know which wires from the original harness, would you share that? It sounds like the answer TWO of us are looking for.
LOOK at the stock coil/distributor set-up.

There's a RED wire that powers the stock distributor module, and the coil. Use that RED wire with a suitable connector spliced-in, to power the 4-pin module coil-in-cap distributor at the BAT terminal.

There's a WHITE wire on the stock coil. Use it on the TACH terminal of the 4-pin module coil-in-cap distributor with a suitable connector spliced-in, to keep the dashboard tach working.

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But that still leaves you to figure out how to provide the ECM with an RPM signal so it knows to turn-on the fuel pump relay. Which is why I said "Good Luck". I have no idea how you're going to do that, although someone else on another forum claims they had the brute-force solution--run two ignition modules, with the 4-pin module actually running the engine, and the 8-pin module doing nothing but hand-jobbing the computer to keep it happy. I had to point out that the associated wiring diagram drawn by the "inventor" and subsequently cleaned-up by another volunteer, failed to power the ignition coil; and posted a correction. That correction is theoretical, I haven't tested the system and I think the dual-module "solution" is a clever if inelegant way to "solve" this problem. Clearly, this is not something I've done, or would consider doing. Therefore, I have no plans to research it further. You want to gut the computer-controlled ignition, you're pretty-much on your own.


No one asked whether or not a mystery transmission would hold up to a 454. For all we know, he's using a chain-driven rear setup from the 1800's.
A general warning to someone about to jump off a cliff can be a good thing. At minimum, it shows that someone is paying attention and cares enough to say something.

We haven't even started talking about how to control the 4L60E transmission--which may or may not be what you, or the OP has.

This is a slow-motion disaster. I can see the multiple problems from here.

No one asked to move this to an lsx / carb swap forum.
I asked. It didn't belong in the general forum when it's clearly part of a carb-swap project.

No one asked about fiery explosions, reading wiring schematics, passive-agressively questioning peoples' skill set or guesswork over sensors. No one asked where to download service manuals. From all the replies, it sounds like everyone knows the answer to everything, so would you kindly go back, read the questions and just answer them? Please? I mean really, are we here to help one another?
Yeah, yeah, yeah. If I see someone about to make a mistake, I try to get them to see the problem before it gets expensive. This is one of the many services I offer.

I will generally stay out of the LSX + Carb Swap section, the Lowered and Bagged Suspension section, the Full Custom Suspension / Cages / Fab section, and I avoid the threads dealing with bolt-on suspension or body lift kits, because in my experience, there's nothing there but trouble unless a person is already SUPREMELY familiar with those projects. A newbie needs an on-site, in-person, real-live mentor to keep 'em out of trouble.
 
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89GMCJOHN

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I did one of these swaps .....short list of things comes to mind ...
Key switched red or pink from the old ignition connector to +12 on dist. white to tach
You will need a FPR to knock down the tbi pump pressure which if I recall is 15 psi ...your carb needs 5-6 psi.
Bonzai mode ;) - Green with a black chaser wire on the Fuel pump relay on the firewall if I recall correctly will need to be cut and the relay wire then connected to a +12 key switched source to manually turn on the in tank fuel pump bypassing your ECM and oil pressure switch combo. As others have stated this is dangerous but when you turn the key off it will turn the fuel pump off ...start or run fuel pump is enabled. Its your call.
 

1owner1990

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There is not always just a single short answer. For you it may be easy. I can't see what you doing. I don't know your skill level. I don't know your knowledge level. Things I see as an easy problem others don't.
You ask for help, great were here, but do something dumb and get called out for it, that's life. It's a learning experience.
All good mechanics, technicians use whichever service manuals applies to what they work on.
I can give you a fish, or I can teach you to fish. What's better for you long term?
We will give you answers and the knowledge, manuals for free.
There is not always just a single short answer. For you it may be easy. I can't see what you doing. I don't know your skill level. I don't know your knowledge level. Things I see as an easy problem others don't.
You ask for help, great were here, but do something dumb and get called out for it, that's life. It's a learning experience.
All good mechanics, technicians use whichever service manuals applies to what they work on.
I can give you a fish, or I can teach you to fish. What's better for you long term?
We will give you answers and the knowledge, manuals for free.
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My skill level? From the powder coated frame in my profile pic to this. Any more questions?
 

1owner1990

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My skill level? From the powder coated frame in my profile pic to

You must be registered for see images attach

My skill level? From the powder coated frame in my profile pic to this. Any more questions?

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My skill level? From the powder coated frame in my profile pic to this. Any more questions?
And another thing @GoToGuy if you don't know the answer, there's no need to chime in with bull$hit about fish and Gospel interpretations. I joined this forum in the hope of sharing knowledge with like minded people. Unfortunately, what I've found are guys who evidently haven't gotten laid since 1998. Blow your smoke up your own ass. I don't need it, thanks very much.
 

1owner1990

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Huh. I figured I'd be the one on the receiving end.

What I see is that you're a wizard at bodywork/painting/cosmetics. FULL respect there. Your skill level at mechanical/electrical is what's important

Huh. I figured I'd be the one on the receiving end.

What I see is that you're a wizard at bodywork/painting/cosmetics. FULL respect there. Your skill level at mechanical/electrical is what's important here.
@Schurkey, haha I took the high road with you last time, when my question got scrutinized - but never answered. Thanks for the props, but with all due respect, I don't need anyone telling me what's important in my build.... in part, because it's not actually my build. My skill level with 31 years as a controls electrician really isn't what's important here, nor is mine (or my 16yo daughter's) mechanical skill set, as the truck runs and drives perfectly. Yeah, a 16 year old girl built this truck right alongside me, wrench for wrench, skinned knuckle for skinned knuckle, tear for tear, smile for smile. Oh, listen to me trying to explain myself. I bought this GMC 1500 brand new, 33 years ago and it came time to pass it on to a girl who actually loves it more than I ever did. The real point here is how she sees these posts of (what we assume are) grown ass men carrying on like a bunch of old hens. Some folks here should be embarrassed for themselves for the 'holier than thou' attitudes and passive aggressive replies. Are we here to help or to harass one another? Unfortunately, we already know the answer, although we just cant figure out why y'all are the way you are. I asked one very simple question from a group of self proclaimed know-it-alls, who, among the group could (maybe) figure out how to change a flat tire... if they could just resist bickering among themselves about which lug nut MUST be loosened first, according to the GM handbook. Get over yourselves! For Christ's sake, we were reading a critique a few days ago, where some poor guy cut a hole in his floor to access a fuel pump and y'all go and get Fire Marshall Bill involved, talking about how the guys truck would explode if he rolled it. Yeah. Rolling it. That's a likely scenario, right? The poor guys just trying to keep his truck on the road, but thats just not good enough, is it? Anyway, why not lighten up? If our build involved egos or playing strictly by the rules, it would have never gotten off the ground. Instead, we went with love, patience and commitment. And it paid off. You guys need to get over yourselves sometimes. Seriously. In this picture is a young lady who built an obs from the ground up and who respects these trucks for what they are. She also respects them for the simplicity of what they aren't. Make yourselves proud, boys. Please. Kids are watching.
 

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RichLo

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I have been letting GoToGuy do his thing since the thread below and have held back commenting about him to defend him or PM him about how to edit his posts. He is a grown man and knows what he's doing so it wasn't my place. I think he has backed off a bit since the posts your referencing in this thread, but I feel like this is the time and place to comment. You have a great story Mr 1-Owner1990 and I hope you and your family stay in this forum.

I just have to say, GoToGuy is one of the most stand-up humans that I have NEVER met!
Please see this thread...

I live in Wisconsin and was considering buying a car from California, which was located over an hour from where he lives. As you read through that thread you'll see the progression but to summarize... He drove out to inspect the car for me and took tons of pictures with an extremely detailed email describing his views and inspection results. I couldn't have gotten half or even a quarter of his inspection if I had the car sent to a shop!

Then when I decided to buy it, I was having trouble getting a deliver driver to align their schedule with the seller he was always in contact with me asking when he could drive back over (an hour each way) so he could verify the car gets loaded and the title work was done right.

ALL OF THIS WITHOUT ASKING FOR A DIME!!!

After everything he did, Literally hours out of his life, gas used and constantly in contact with both myself and the seller he never asked for any re-imbursement. I had to make him tell me how to send him some sort of re-imbursement after the car was loaded and the delivery driver was leaving the sellers property!

His screen name fits his real-life personality perfectly. Please dont hold some greatest-generation-grit over his head. He is trying to help. I dont know your exact age GoToGuy so I hope I'm not over-estimating but you have the same no-nonsense and give the T-shirt off your back personality as the people that I look up to.

EDIT: I was just re-reading that thread and I forgot GoToGuy even spent time dealing with the California DMV to make sure the Title was valid, and transferrable to another state! Who does that just out of the kindness of their heart for a complete stranger???
 
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Schurkey

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@Schurkey, haha I took the high road with you last time, when my question got scrutinized - but never answered.
Never answered? I answered your question BEFORE YOU ASKED IT. I replied with my answer to the original poster.

You QUOTED MY ANSWER in Post #5 and again in Post #6, when you asked the same question as the original poster.

And in the process of answering that poster's question, I also remarked on some of the down-sides to this particular swap--that getting the computer to turn on the fuel pump is going to be a problem, getting the computer to control an automatic transmission is going to be a problem, and that extra torque into the original-poster's 6-cylinder spec transmission is going to reduce it to an oily metal milkshake.

The 4-pin module HEI needs to have the red power wire connected to the BAT terminal on the cap. The tach in the dash needs to have the white wire connected to the TACH terminal, just as you said.

If you know which wires from the original harness, would you share that? It sounds like the answer TWO of us are looking for.
@Schurkey could you share the wisdom please?

Now, true enough, I did not specify which "red" wire, and which "white" wire until Post #11. I assumed that powering a "modified" distributor with on-board module and ignition coil would inherently mean using the wires attached to the existing module and ignition coil, which are "red" and "white" wires.
LOOK at the stock coil/distributor set-up.

There's a RED wire that powers the stock distributor module, and the coil. Use that RED wire with a suitable connector spliced-in, to power the 4-pin module coil-in-cap distributor at the BAT terminal.

There's a WHITE wire on the stock coil. Use it on the TACH terminal of the 4-pin module coil-in-cap distributor with a suitable connector spliced-in, to keep the dashboard tach working...
But there still remains the problems of safely turning on the fuel pump to avoid long-cranking-time if the carb float bowl is empty, (NOT via a power source switched by the ignition) and how to control a 4L60E transmission, or the torque converter of a '700 or 4L60. PlayingWithTBI did a fine job of explaining WHY the fuel pump shouldn't be powered by the ignition. I don't have a good answer for how to handle that...but I have a bad answer, which is to use double ignition modules. And I linked to that "solution" so folks could decide for themselves.

I don't see a problem with how I handled this.
I don't see a problem with how anyone else volunteering information to you in this thread handled this.

Glad you're spending quality time with your daughter. Glad she's spending quality time with you.
 
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