5.3 injector upgrades
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5.3 injector upgrades I have a 5.3 vortec and everything is stock on it but I'm ordering headers and a granatelli MAF. I'm looking at new bigger injectors but I'm not sure if I have to upgrade anything else for new injectors to work or will 36lb injectors fit on my stock fuel rails. Will that work or will I need other accessories for it to fit properly and run well?
Do not put some POS like a Granatelli on the truck. Thought the trucks got the same MAF as the ZO6, chasing the wrong things there. As a couple of us said in the other thread injectors are the wrong place to look as well.
Last edited by 96capricemgr; Apr 23, 2014 at 04:43 PM.
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That maf is a waste of money your stock one is more than fine for your power level. With just headers you won't need to upgrade your injectors. The 8.1 truck injectors are a direct replacement and they are 31 lbs . If you change injectors you will need to have it programmed before you run the car. The car injectors are a different height and plug than the car injectors. You never said what year is your 5.3 ?
That maf is a waste of money your stock one is more than fine for your power level. With just headers you won't need to upgrade your injectors. The 8.1 truck injectors are a direct replacement and they are 31 lbs . If you change injectors you will need to have it programmed before you run the car. The car injectors are a different height and plug than the car injectors. You never said what year is your 5.3 ?
So they are 31#s at stock fuel pressure, fit the stock fuel rail, and use the stock injector harness?
Why are you interested in injectors?
30lbs injectors can support in the neighborhood of 500rwhp NA through a 4L60E. I know that contradicts a lot of what you will read but that comes from people paying too much attention to the computer and NOT the engine.
Why are you itching to swap injectors on a stock 5.3l?
30lbs injectors can support in the neighborhood of 500rwhp NA through a 4L60E. I know that contradicts a lot of what you will read but that comes from people paying too much attention to the computer and NOT the engine.
Why are you itching to swap injectors on a stock 5.3l?
Why are you interested in injectors?
30lbs injectors can support in the neighborhood of 500rwhp NA through a 4L60E. I know that contradicts a lot of what you will read but that comes from people paying too much attention to the computer and NOT the engine.
Why are you itching to swap injectors on a stock 5.3l?
30lbs injectors can support in the neighborhood of 500rwhp NA through a 4L60E. I know that contradicts a lot of what you will read but that comes from people paying too much attention to the computer and NOT the engine.
Why are you itching to swap injectors on a stock 5.3l?
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From: Monroe,NY
I have a 2004 5.3 with the truck intake and they are a direct replacement. Going by hptuners they flow 29.4 lbs at wot on a returnless style fuel rail. And they plug right in to the truck harness unless you have the flexfuel injectors which you wouldn't need to upgrade then.
Last edited by gagliano7; Nov 29, 2017 at 10:26 AM.
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I think you may have confused my post with the original poster. My setup is different, and Im looking for a simple injector upgrade in the event my 23.5# dont cut it. Trust me though, if my tuner doesnt say i need more injector, i wont waste the money. Plenty of other place id rather spend it...
I was replying to the OP. If he has a stock 5.3l why would he want to go to a larger injector? The aftermarket MAF/larger injector thing sounds almost like he is maybe getting info from older Mustang setups where the pcm wasn't easily reprogrammed or something goofy like that. Sure as hell isn't getting reasonable ideas from anyone with the slightest GM knowledge about anything made in the last 20 years.
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Great thread!!
So i have a 1999 silverado 5.3L with an ls1 intake, my intake came complete, throttle, stock injectors,fuel rails? if i wanted to upgrade my injectors will i have to change n e thing? my MAF is stock as well..
So i have a 1999 silverado 5.3L with an ls1 intake, my intake came complete, throttle, stock injectors,fuel rails? if i wanted to upgrade my injectors will i have to change n e thing? my MAF is stock as well..
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I have some questions about my injector/fuel system too. I want to upgrade my fuel system (injectors/pump, etc) but need advice on what to get. Goal is around 800hp with boost. I have a 1999 5.3L sierra with some goodies such as a stage 3 TSP cam 216/220, Lr4 high compression pistons and new rings, ls7 valve springs, 2.0 Corvette intake valves, polished and ported heads and LS1 long tube headers. Tuned by TSP and made roughly 430-450whp. All N/A.