Putting a carburetor in a TBI based truck.

AyWoSch Motors

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I'm intersted in possibly putting a carburetor on my 92 TBI 350.
I have an edelbrock 4bbl dual plane performer and a stock cast iron Chevy 4bbl intake, an Edelbrock avs2 and a Rochester Quadrajet, an HEI distributor, a mechanical fuel pump, pump plate, push rod, and mechincal pump style sender unit, that I was contemplating putting on my engine, just to simplify it and make it more reliable.
(I'm old fashioned, not much for computers) Curious what else I would need to do such a swap?
And the biggest thing holding me up from doing that, is would the rest of the truck work on its stock wiring and computer without having to redo everything or buy a costly wiring harness.
Would the computer still allow the gauges to work as well as other things?
If im making everything basically mechanical and old style, the computer isnt doing much anymore, so could I just unplug all of that, and itd be fine, or would something go terribly wrong.
 

tpass

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Honestly its not really all that difficult from what i've seen.. i almost did it on my 1993 but stuck with the TBI because my 4l80E needed the throttle position sensor. you probably don't have that issue but you will probably need to fab something for a kick down cable. Also the intakes are not a direct swap for TBI.. the center most intake bolts are vertical on the TBI.. the older SBC intakes need those holes modified.

There so many video's on youtube about it.. you should watch a few to get a consensus on what you need.
 

454cid

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I'm intersted in possibly putting a carburetor on my 92 TBI 350.
I have an edelbrock 4bbl dual plane performer and a stock cast iron Chevy 4bbl intake, an Edelbrock avs2 and a Rochester Quadrajet, an HEI distributor, a mechanical fuel pump, pump plate, push rod, and mechincal pump style sender unit, that I was contemplating putting on my engine, just to simplify it and make it more reliable.

I'd say that unless you know carbs inside and out, backwards and forwards, it's a bad idea. TBI is not state of the art anymore and is quite reliable and well known on the forum.

You might need the computer to operate the transmsion if it's an auto.... I'm not sure if the 92 would be a 700r4 or a 4L60e.
 

AyWoSch Motors

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I'd say that unless you know carbs inside and out, backwards and forwards, it's a bad idea. TBI is not state of the art anymore and is quite reliable and well known on the forum.

You might need the computer to operate the transmsion if it's an auto.... I'm not sure if the 92 would be a 700r4 or a 4L60e.
It's a 4L60E, but I'm soon to put a 5 speed manual in most likely.

And I do know carburetors well, most everything else I own are carburated, so I'm used to it.
I respect the TBI, they're very reliable until they aren't if you know what I mean.
They dont make much power, you cant really tune them much, and if you have any electrical issues, they stop running. Guess I'm just old fashioned and like what I'm used to.
 

AyWoSch Motors

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Honestly its not really all that difficult from what i've seen.. i almost did it on my 1993 but stuck with the TBI because my 4l80E needed the throttle position sensor. you probably don't have that issue but you will probably need to fab something for a kick down cable. Also the intakes are not a direct swap for TBI.. the center most intake bolts are vertical on the TBI.. the older SBC intakes need those holes modified.

There so many video's on youtube about it.. you should watch a few to get a consensus on what you need.
I have an older 4bbl cast iron intake, with the center bolt holes cut at an angle with the wedge shaped washers.
 

tpass

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you can use the in tank fuel pump with the carb and a pressure regulator.. its not a high pressure pump anyway.. 15psi max i think
 

98 Nitro

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If you are driving it in winter in the northern half of the country keep TBI, if not and you are comfortable with carb go for it. Your trans would be a 4l60 (700r4) no e in 92. There are aftermarket intakes with the 87-95 bolt pattern and even GM had them in 87-88 Monte SS and maybe other G bodies with 305s.
 

PlayingWithTBI

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you can use the in tank fuel pump with the carb and a pressure regulator.. its not a high pressure pump anyway.. 15psi max i think
Yes, the OE 75L/Hr TBI pump is anemic at best. It'll only support ~230HP then it'll run out of juice. I'd go with a higher volume in-tank pump (like an EP381) with a bypass AFPR.
 

351FUN

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It's a 4L60E, but I'm soon to put a 5 speed manual in most likely.

And I do know carburetors well, most everything else I own are carburated, so I'm used to it.
I respect the TBI, they're very reliable until they aren't if you know what I mean.
They dont make much power, you cant really tune them much, and if you have any electrical issues, they stop running. Guess I'm just old fashioned and like what I'm used to.

Are you 100% on that? 1992 was the 4L60, not the 4l60E. The 4L60 is a renamed 700r4.
 

Erik the Awful

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If I remember right, 1993 was the changeover year from the 4L60 to the 4L60e. Do you have a TV cable? If so, it's a 4L60/700R4.
 
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