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Old 08-25-2013, 04:28 PM   #1
birdrx7tt
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Ditching the TBI

Looks like I will be getting rid of the tbi and going to a carb I have a 90 Crew 1 ton has anyone done this what do you use for a fuel pump ? What can go and what needs to stay ?
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Old 08-25-2013, 05:34 PM   #2
csdineley
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Re: Ditching the TBI

I plan on doing it at some point. But it's doesn't seem to be a very popular thing to do. And if you have to pass emissions for an inspection, It won't pass. I'm planing on using a mechanical fuel pump. But others use a fuel pressure regulator with the stock in tank pump. Also need a distributor, intake, Carb (of course), and some say a different cam.
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Old 08-25-2013, 06:57 PM   #3
Zane M
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Re: Ditching the TBI

Check with a mechanic/emissions station to verify you can get it to pass the visual inspection portion with the carb vs. the original fuel injection(it can be tuned to pass the sniffer portion, provided the truck will already do so with the TBI).
You can use the existing pump, provided you install a regulator that you can adjust the pressure down to whatever carb you end up choosing will run with. If your block has a provision for a mechanical pump, you could do the switch to mechanical, but you will need to verify your cam has a concentric to run the pump(I'm not sure on a '90).
Replace your distributor, intake, and install a carb. You will have to do some engineering for the fuel lines.
Being in Utah county, you are going to need to keep all your emissions equipment, including the EGR.
Once you get it all buttoned up and have done the initial tuning based on the instructions of the carb manufacturer, find a shop that specializes in carb tuning and have them set it up to pass emissions. I know from personal experience that what may be optimum baseline settings are not going to get you into the pass emissions realm.
You will obviously be able to get rid of the wiring for the O2, TPS, MAP, IAC, etc.
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Old 08-25-2013, 07:35 PM   #4
Tx Firefighter
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Re: Ditching the TBI

You didnt specify which engine you have, but if you have a big block you wouldn't need to swap intakes. Just remove the adapter and there is a standard spread bore pattern beneath it. On my truck, the fuel pump provision is there, just blocked off so a manual pump would be cheap and easy.
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Old 08-25-2013, 09:51 PM   #5
birdrx7tt
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Re: Ditching the TBI

Thanks guys Ya it has a 454 soon to have a blower and carb I just wasn't to sure about the fuel as far as what most people do mechanical or pressure regulator. I don't have to worry about doing emissions on it .
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Old 08-25-2013, 09:53 PM   #6
birdrx7tt
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Re: Ditching the TBI

So if I go the mechanical pump route do I have to pull the in tank electric pumps or are they a draw through design ?
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Old 08-25-2013, 11:06 PM   #7
BONUSCAB
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Re: Ditching the TBI

So you're taking your stock motor and slapping a motor on it?
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Old 08-26-2013, 07:01 PM   #8
birdrx7tt
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Re: Ditching the TBI

Motor wont be stock .. Heads, roller cam, full exhaust, Ignition .
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Old 08-26-2013, 07:59 PM   #9
Hevy
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Re: Ditching the TBI

If you're going to run a blower I'd stick to an electric fuel pump.
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Old 08-26-2013, 09:22 PM   #10
suxtobu65
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Re: Ditching the TBI

Blower on a 1 ton.. Seems to be kind of a waste, no? I ditched the tbi in my 88 cc dually, Gained 2 mpg and more mid range power..
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