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Semper Fi
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154 Posts
Discussion Starter #1
I'm sure it's been posted about somewhere on here, but I can't seem to find it. So I'll make my own thread.

I have a 77 GMC 1500 with the original 350 motor in it. I've got a buddy with a TBI 454 that i would like to put in my truck.

I was wondering if someone could give me a quick over view over what all I would need to get/do to my truck in order to put a fuel injected engine in it.

I've got no experience in this area, so any advice/help would be awesome. :shake:
 

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i'll take a shot at it, and hope others will chime in with what i missed. first we'll talk fuel, and you'll need an electric pump that is capable of 35 to 40 psi at the tbi unit. i have seen inline pumps work for this kind of swap, and there are companys that can supply you with a in-tank setup to accomplish this task (apeusa.com is one), and the return must go back into the tank within 1/2" from the bottom because of high pressure return, possible vapor build-up that can create unsafe pressure in the fuel tank. the easiest/safest way to go is get a tbi tank for an 87 1/2 ton because this was the first year for the tbi and the 87 is the same body style as yours and will bolt right in (plumbing would still be custom fabbed unless u use all 87 plumbing too). the reason you need a fuel injection tank is because it has an anti-slosh sump pickup in the tank so the pump won't cavitate/starve in turns and always has fuel flow. if you go with the 87 tank you'll need a fuel pump that will flow enough for the big block which would have to be a 3/4 or 1 ton 454 equipped truck pump. the 3/4 or 1 ton tanks may work but are usually larger, i'm not sure, but the pump will work. again this easiest because it's all facory setup with the fi pump in the tank.

the engine will need the tbi distributor, the ecm, ecm harness, the exh. manifolds or headers with the O2 sensor provision, and you must keep all sensors that come on the engine (water temp, oil press, egr, etc... because the ecm reads these sensors feedback to determine proper fuel metering and timing.

other than wiring and install that is about it, and keep in mind if this is an unmodified engine all or nearly all the parts you'll need should be off the shelf GM parts and little or no fabbing is really needed except the wiring. get a schematic of the wiring for your year tbi and you'll be able to delete any un-needed wiring from the harness and know where to wire the ones you have to keep. it would be great if you have access to the donor truck to rob your needed conversion items from.

good luck
 

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Semper Fi
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154 Posts
Discussion Starter #3
Thanks for the advice man!

Do you know where a good place to get the wiring diagrams would be?
 

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366 Posts
You need a pump capable of 18-20 psi TBI's range not 40-50psi TPI's range.

But the 86-88 3/4 and 1 tons would have such a set up or 86-90 3/4 burbs before the body change should have them too.

Or there has to be an aftermarket pump that can run at up to 20 PSI. I would check with Holley as they have the super bitchen Comander 950 TBI.
 

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Semper Fi
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154 Posts
Discussion Starter #5
Thanks for your help.

I had found on another forum that an Airmax E2000 (if I recall correctly) works perfect for the TBI, and it pretty cheap, so hopefully that will work for me.
 

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i always catch you hatin'
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606 Posts
TBI sucks, your sig kicks ass.
X2

a stock tbi 454 makes about 230 hp your 350 makes prolly about 250, and weighs a hell of alot less....i would just build a decent carbed 383 and drop that in with an 1/8 of the hassle/cost, or get a carbed bbc intake and go that route, it will save you from wiring, setting up an ecm, and changing your tank
 

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LQ9 club member
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LS motors FTW
 
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