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-   -   Carbed 5.3 instead of fuel injection (https://67-72chevytrucks.com/vboard/showthread.php?t=658436)

russellrox 01-31-2015 02:35 PM

Carbed 5.3 instead of fuel injection
 
Has anyone used this Accel unit to convert your 5.3 to a carbed unit with a holley intake and carb, looks pretty simple, or would you of rather done all the wiring and make it full fuel injection.

Indian113 01-31-2015 04:20 PM

Re: Carbed 5.3 instead of fuel injection
 
When I put the 5.3 in my S10 I checked into going that route. I decided against it because I could buy a full reworked Harness for around the same as all that stuff was going to cost. The way my truck runs, starts and mpg's have made me very happy I stayed FE

66LSx 01-31-2015 05:28 PM

Re: Carbed 5.3 instead of fuel injection
 
If your doing a carbed 5.3L.....

Save your money and just put a normal 350 in it.


my Fuel Injected 5.3L was the reason I did it....

More HP (vs carb)
Simply the easiest starting possible (vs carb)
Any auto store has in-stock any part needed (vs carb)
Easy to diagnose (read: my truck stops running.check engine light and I bring it to autozone and plug it OBDII in to find out exactly what is wrong... a carbed truck stops running and you go.... uhhhhh ? where do i start trouble shooting :m6:

Not even comparable MPG


Keep it FI... you'll regret it if you don't.

Oh.... and did I mention throttle response?

https://www.youtube.com/watch?v=xLK1NFG2rkU


https://fbcdn-sphotos-c-a.akamaihd.n...3b77e4cedd70c8

joedoh 01-31-2015 05:50 PM

Re: Carbed 5.3 instead of fuel injection
 
so the carb gets rid of the EFI portion, but what will you do about spark? no where to stab a distributor in.. you will still need the ECM and associated wiring and ECM flash to run the coil packs.

so I agree with above, if you are going to run a carb, get a carb 350. the GM EFI is about as simple as something gets, plenty of tutorials out there on modifying your own harness and you can disable the security in the ECM cheaply if you dont add a tune (thats where the money is)

russellrox 01-31-2015 05:53 PM

Re: Carbed 5.3 instead of fuel injection
 
the accel unit controls the coil packs, using the crank sensor so no need for a distributor, where are you guys buying your harnesses to work with the 5.3, or are you just modifying the one out of the truck it came from. I guess I will be staying with fuel injection then, just wanted to see what the general opinions were. Thanks for all the great info.

joedoh 01-31-2015 06:22 PM

Re: Carbed 5.3 instead of fuel injection
 
you only need to change the harness if the ECM doesnt fit in the rough location it was in the donor. otherwise all the plugs you need are already there and you can find the BATT and IGN input wires. some people use the simplified harnesses to clean up, some use them to run aftermarket gauges. you WILL need an ECM flash, to get rid of the key security and allow the engine to start.

those ignition controllers are $300+ bucks!

66LSx 01-31-2015 06:50 PM

Re: Carbed 5.3 instead of fuel injection
 
Quote:

Originally Posted by joedoh (Post 7028092)
those ignition controllers are $300+ bucks!

FYI The ignition controller and carb/LS intake and carb itself are more then a brand new PSI conversions harness (which allowed me to put my ECM under the dash in-cab) and a retune by LT1swaps. (to remove emissions and security)

Note: You get some pretty cool features using the ECM.... I for example left my tow-haul feature enabled on my computer.... a simple momentary push button on my 66 dash and viola... tow haul mode... errr should i saw haul a$$ mode....

Technology is great once you embrace it (and thier really not too hard to wire... just patience)

cableguy0 01-31-2015 07:30 PM

Re: Carbed 5.3 instead of fuel injection
 
Either way keeping the injection is cheaper. if your not terrified to open the harness yourself its definitely cheaper. I did a harness and mailed the computer to be tuned. Total cost to keep injection was about 100 bucks. It was a complete engine in the first place but I eliminated the trans control and emissions stuff.

truckster 02-01-2015 02:13 AM

Re: Carbed 5.3 instead of fuel injection
 
Quote:

Originally Posted by 66LSx (Post 7028062)
Easy to diagnose (read: my truck stops running.check engine light and I bring it to autozone and plug it OBDII in to find out exactly what is wrong... a carbed truck stops running and you go.... uhhhhh ? where do i start trouble shooting :m6:

I won't argue with the benefits of fuel injection, but diagnosing a carbed engine is about as easy as it gets. There are only three elements: Fuel, air, and spark at the proper time. No sensors or computers.

b454rat 02-01-2015 10:11 AM

Re: Carbed 5.3 instead of fuel injection
 
I don't see the point in going to an LS if your gonna stay with a carb. Buddy did this, but he is experimenting with it, see where any weak spots are. He is running a hair dryer, weakest stock link was the intake, can't handle more than 20 pounds or something....

crazy longhorn 02-01-2015 06:28 PM

Re: Carbed 5.3 instead of fuel injection
 
I have heard it said, that it is like a religion, or political discussion? It can be a big bag of mess! For my app, I went carbed....used engine, I had already rebuilt the top end, & gaskets /seals. The truck intake was warped, dirty injectors, & in need of a wiring upgrade on the old truck. The dedicated fuel system, would have cost me as well (to run the fuelie)? My Brother handed me a 600 Edelbrock...not a hand out, a hand UP ;) For me it was cheaper, to get that old truck rolling, & she don't run bad at all. Yes, you loose some of the "magic', that the fuelie had, such as the mileage? also the cold start drivability. I still have all the parts from the LS truck, but would go aftermarket, on an LS-1 setup, if I were to go fuel injected:chevy: Longhorn


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