Cam swap....injectors needed?
03-30-2011, 08:12 AM
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Cam swap....injectors needed? For those of you who have upgraded cams in your V, did you need to swap out injectors? I have some ford green tops in the garage I was saving for a 408 build. If I need to use them I can but I wanted to get input from you guys first. I could always take them with me to the tuner, just in case.
On a similar note, I've read that the injectors should see no higher than 85% duty cycle. Any higher calls for an larger injector. Input?
On a similar note, I've read that the injectors should see no higher than 85% duty cycle. Any higher calls for an larger injector. Input?
03-30-2011, 09:02 AM
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For those of you who have upgraded cams in your V, did you need to swap out injectors? I have some ford green tops in the garage I was saving for a 408 build. If I need to use them I can but I wanted to get input from you guys first. I could always take them with me to the tuner, just in case.
On a similar note, I've read that the injectors should see no higher than 85% duty cycle. Any higher calls for an larger injector. Input?
On a similar note, I've read that the injectors should see no higher than 85% duty cycle. Any higher calls for an larger injector. Input?
03-30-2011, 09:10 AM
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They are 42lbs at 43.5psi....so a bit more on our rails. If theres not a need for them, I'll save them for the 408. But if I must use them I will...
03-30-2011, 04:50 PM
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just a cam? what size? im running a bone stock fuel system but im sure my injectors are probably maxed out. They say 80% duty cycle is the max you want but itll still keep up with the demand at more then that. If you have them I dont see why you wouldnt use them though.
03-30-2011, 06:01 PM
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itsslow, looking at an EPS 226/234@113 .598 intake .600 exhaust. From what I've read, it seems that you want it less than 85-90% duty cycle. I really want to save the green tops for a 408 i'm building. It will never be done if I keep stealing its parts!!!
03-30-2011, 11:01 PM
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My cam is 236/242 .615/.615 and I am pushing 110% duty on the street. They were showing 105% on the dyno because of the lighter load. The afr is not falling off and still adjusting as I tell it to, but anything over 100% and they aren't pulsing correctly anymore and pretty much just running wide open. Some people think it doesnt atomize the fuel correctly when they are being pushed like this. It is not uncommon for people to pick up a good bit of power by upgrading injectors even though they are not running lean on the stockers.
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03-30-2011, 11:33 PM
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I have 42lb injectors on my big cam setup. Duty cycle is at 53% at wot. Stock injectors were at 113% at wot. Not truly required, but its good insurance, plus u gain better fuel control.
you'll need to have 32 lb.-34 lb. injectors to be at 80% duty cycle and 58-60psi fuel pressure. 
