How would you make a TBI 454 as analog as possible?

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Sentinelist

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Getting rid of TBI in favor of a carb and points ignition, and going to manual torque converter clutch lockup is insane.
[EDIT] Aren't the 93--94-ish and newer transmissions electronically-controlled? No "real" valve body, TV cable, vacuum modulator, governor, etc.? [/EDIT]

Even the heater and wiper controls are electronic, along with the cruise control and ABS.

Do you have a problem with the "solid state" diodes in the alternator?

Why not just buy a horse?

Is it though? Seems like a pretty popular route for those fed up with troubleshooting EFI hassles and tunes from the searches that I've done here. Maybe you weren't aware. Again, going back to my concerns and objective here, sticking with EFI (or let's face it- picking a far nicer GMT-800 for the same price, such as the 2005 Z71 Burb I used to also have), is what would be insane for my use case. Not worried about the heater and wiper controls and other ancillaries- I'm more interested in a drivetrain that functions without electronics. And where that's not possible, such as the alternator as you pointed out, a new spare can safely be stored away to swap in if needed. Cheap and easy.

Though I do still want a horse just for kicks... my neighbor has a stunning retired thoroughbred 16-hand, but my veterinarian wife has always said no due to medical costs... even if I look damn good on one.

Holy crap man, lighten up. If you really want to go "straight up mechanical" (lol) engine control, buy a 12V cummins and then go bother those guys with your paranoia.

Here in the real world, we go forward with technology. We are up to direct injection and PWM fuel systems. It's fun, take off your tin foil hat and join us.

Ah no worries, I have vehicles for days I need to 'lighten up', and those days aren't infrequent. Just wafted around in one of them today and it was indeed fun, but is absolutely incapable if times got tough. My daily drivers are thoroughly modern and make any GMT-400 look like an International Scout. (Which would also be a great candidate if they made a 4-door model- 12V Rams too sadly enough) But my daily drivers, capable with 4WD and locking diffs and KO2s as they have, may also be rendered technically doorstops in such an event. As would yours. That'd kinda suck wouldn't it? Yes, I mean if you cared. As I mentioned, what I'm after is purely an analog backup vehicle. And with that objective and family in mind, money is of little object.. But if you want to be the grasshopper in the Aesop fable vs. the ants, well, somebody has to be. Do you like deer corn? I'll leave a sack out for you. :)

My suggestion for ultimate simplicity would be to buy a stock TBI and keep it a stock TBI. Much more reliable and easier to troubleshoot than a carb-swapped engine. If you are worried about obsolescence, spend $500-$1000 and buy backups for all your critical sensors + a spare ECM.

Can-do on buying and securely stashing backup parts- that's what I figured would be needed. Just hoping I can put together a general list (and for future reference for others here) of what components would be needed to address this.

I have looked into this fairly deep.

You could get the tbi 454. Add an edelbrock intake and 1405 carb w/electric choke kit. HEI distributor, wideband O2 sensor to tune the carb, manual valve body in trans with a good torque converter. Remove the oem cluster and add other gauges etc..

The main thing that stopped me from doing this is the cost. Add all of that stuff up and you could spend a chunk of change. If you are building a truck where most of the oem parts are junk and will need to be replaced anyways, it might make sense. If you buy a truck that runs and most of the stuff works as is, it's hard to justify the cost of changing it all.

Certainly agreed in principle normally. Thanks very much- I posted this hoping to get a reply like that. I wouldn't mind dumping a few grand back into the truck to get it setup like this even if that exceeded the value of the truck itself. It might. If you were to have done it, which specific parts would you have picked and from what vendor? I'm scoping Summit but maybe there's a better option out there. Links would be awesome that I could tally up and plan around. I can do most of the work myself but have a willing indy shop as well.

What you're looking for is a 70's Suburban with a 454,before computers and any other smog crap.

Indeed sir. I actually went and looked at an early-80s K2500 Burb last week. Haven't ruled it out. I'm just hoping I can push my luck with a GMT-400, even if it takes a true carb conversion and a handful of other parts to generally make it analog for running and driving.
 

Sentinelist

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Perhaps a moderator will move this thread to the LSX + Carb Swaps section.

Much appreciated- I didn't see that area at first. That's probably more applicable for this.

And really, joking aside, just trying to get some info and feasibility on maybe an interesting technical angle here without trying to look like a nutcase which I'm really not (or that's actually what nutcases say isn't it). Thanks for some of these helpful tips so far, guys. Aside from a few old tractors I have and my ex-6.5, all that I know and have experience in that's roadworthy is EFI, so am hoping to broaden my scope here back in time with carbs and see if I can make something old work well for a curious need today. Cheers.
 

Schurkey

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Maybe you need to define "analog".

Some of what you're posting is that you'd be opposed to semiconductor/solid state non-digital circuits, too. That rules out HEI.

You want something that might survive EMP, you're looking at an old-fashioned generator not an alternator, and "hollow-state" (vacuum tube) not solid-state electronics in the radio.
 

Sentinelist

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I have looked into this fairly deep.

You could get the tbi 454. Add an edelbrock intake and 1405 carb w/electric choke kit. HEI distributor, wideband O2 sensor to tune the carb, manual valve body in trans with a good torque converter. Remove the oem cluster and add other gauges etc..

The main thing that stopped me from doing this is the cost. Add all of that stuff up and you could spend a chunk of change. If you are building a truck where most of the oem parts are junk and will need to be replaced anyways, it might make sense. If you buy a truck that runs and most of the stuff works as is, it's hard to justify the cost of changing it all.
(first see my reply to you above)

I'm sure these aren't the exact parts in the attached image, but taking a stab at it. Can you or someone please confirm specifically what I'd need for a 1994 454? These costs don't scare me. Though something I'll probably work through gradually between now and summer. Let's call it an analog spring tune-up for good measure... Also, can this same kind of conversion be done with the EFIs or only the TBIs?

Looked hard at (and learned more about) 12V Cummins trucks online today as well, and while a contender, even with a camper shell the family aim keeps me coming back to Suburbans for the big cabin and familiarity I have with them where possible. For the past ten years I've always had some Suburban variant in the garage. A 12V Cummins swap is probably the best answer, and I think I saw at least one of those done on here. But not the most realistic necessarily, and love my GM mills if I can make them work. When my 6.5 threw a rod and died, I had a mil-spec P400 Optimizer dropped in with a bigger turbo. I think that's what it was called. Been several years ago and a time shifting pandemic since then. Anyway:

Candidate A: https://www.cars.com/vehicledetail/76f1bba7-71a3-454e-9ee1-a79fbe2fcced/

Candidate B: https://www.cars.com/vehicledetail/e30c292f-0c2c-4e4a-b331-92f99212cb8c/
 

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letitsnow

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(first see my reply to you above)

I'm sure these aren't the exact parts in the attached image, but taking a stab at it. Can you or someone please confirm specifically what I'd need for a 1994 454? These costs don't scare me. Though something I'll probably work through gradually between now and summer. Let's call it an analog spring tune-up for good measure... Also, can this same kind of conversion be done with the EFIs or only the TBIs?

Looked hard at (and learned more about) 12V Cummins trucks online today as well, and while a contender, even with a camper shell the family aim keeps me coming back to Suburbans for the big cabin and familiarity I have with them where possible. For the past ten years I've always had some Suburban variant in the garage. A 12V Cummins swap is probably the best answer, and I think I saw at least one of those done on here. But not the most realistic necessarily, and love my GM mills if I can make them work. When my 6.5 threw a rod and died, I had a mil-spec P400 Optimizer dropped in with a bigger turbo. I think that's what it was called. Been several years ago and a time shifting pandemic since then. Anyway:

Candidate A: https://www.cars.com/vehicledetail/76f1bba7-71a3-454e-9ee1-a79fbe2fcced/

Candidate B: https://www.cars.com/vehicledetail/e30c292f-0c2c-4e4a-b331-92f99212cb8c/

Summit is where I get all of this kind of stuff from.

From your screen shot - You will also need an electric choke kit for that edelbrock 1405, unless you want to hook up a manual choke and pull/push it each time you start cold. Also with that carb - it is going to be a low to mid range carb. It is a bit small for a big block. If I did a 454 with a carb, that is what I'd buy for my needs, but if you are after big power on top, you probably want a 750cfm+ carb.

You might also need an intake manifold? I don't know what the 454 tbi intake manifold is like. Does it have room for a 4 barrel? If you did this to a newer (vortec) 454, you for sure would need an intake manifold.

You will need a fuel pressure regulator that adjusts down to 5.5 psi, best if it also has a return line to keep the fuel cool. Might want to get a heat insulator to go under the carb, as some have issues with the edelbrock vapor locking without the plate and fuel return style fpr.

I don't know enough about the distributor (is that HEI?), or the manual valve body to comment on that. I was going to buy the summit brand HEI if I did it. I also don't know enough about wide band O2 sensors - but the one that you picked seems expensive.

If you do this, you will have to manually move the shifter for each gear change. You would also need to put a toggle switch (or something) to engage/disengage the TCC every time. Just be sure that you want it bad enough to do it.
 

letitsnow

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Next concern would be gauges and cruise control - you might be able to make them work, but I don't know how. If I do this, I will spend the $$$ on an aftermarket cruise control and gauges.

My total cost to build one as I wanted was around $12-15,000. That was with a reman 454 vortec long block and trans shop rebuilding my 4l80e with/for the manual valve body. To me that is too much money to basically stay the same or go backwards in driveability. I'm sure that it can be done cheaper, but it might take a bunch of messing around/time to make it work.
 

RichLo

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Full manual valve body for your trans probably isnt the best idea unless you add a ratchet shifter in comfortable reach. Rowing the column shifter up and down would get real old real fast.
 

Erik the Awful

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Man, I can go down a rabbit-hole of stuff stuck in the back corners of my head on this one.

EMP is waaay overrated because of movies. It's a massive magnetic pulse, and that's it. The pulse's strength diminishes quickly with distance. An electric circuit doesn't magically quit because of an EMP, the magnetic pulse moves through the circuit, inducing a voltage. If the resulting current is higher than the circuit can handle, you get the same failure you'd get from drawing too much current. Depending on the proximity to the pulse, some electronics will survive, and some won't.

A good analogy is the old Intel Celeron 300 processors. I had a friend who bought a Celeron 300 for his computer build, and I bought a Celeron 333. A few months later overclocking became a hot thing. The 300s could be successfully overclocked to 450mhz, but if you overclocked a 333, there was a 90% chance it would brick. The 300's circuits were a bit overbuilt, and the 333s weren't. With an EMP, I'd guess a Celeron 300 would have a better chance of surviving than a Celeron 333. Even then, there are quality differences in the same type of component. My next computer build was an Athlon, and when the Athlons came out, I read an article on how they were grading the Athlon 1.2ghz, 1.1ghz, and 1.0ghz chips. They all came off the same production line, with the same design. They all got tested and sorted by capability. There were over a million transistors in an Athlon, and the best chips had over 95% of the transistors working when they were tested. These got sold as 1.2ghz chips, while the ones that had 93% of the chips working got sold as 1.1ghz, and the ones that had 90% working were sold as 1.0ghz. Same chip, it was just a question of how well the manufacturing process worked that determined how well the chip performed.

That brings up the robustness of the electronics. Auto electronics are typically designed with a bit more robustness than a TV that hangs on a wall and never moves. When the current chip shortage started, I heard a bit about how the chip manufacturers were all really happy to sideline automotive chips because the technology to produce them is about twenty years old and making them requires working with old equipment. They aren't bleeding-edge chips with a delicate production process. The techniques have been optimized and the yields are optimized to reduce bad chips. These are going to be less susceptible to EMP.

Anybody remember that space launch that happened a few years ago, and the satellite failed almost immediately because they'd used off-the-shelf chips instead of older, ruggedized chips that could handle solar radiation? The ruggedized chips would be more likely to survive.

EMP is not a magic "kill everything electronic" bomb. You're dealing in chances.
 

RichLo

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Or, simply install a Faraday cage around your electronics :waytogo:


Almost like the metal skin surrounding a suburban, lol.

If your truck was ground zero for an EMP pulse, I wonder if any modern distributor components would survive or even the low voltage side of a ignition coil. Might have to go back to a magneto
 
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