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Duty cycle and load

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Old Apr 10, 2014 | 02:47 PM
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Default Duty cycle and load

Quick question on my injectors in the fast EZ TB setup on my LS3. They are showing a max of 78% on duty cycle and 97% load at my fuel pressure of 43 psi. Is that ok, or would it be a good idea to up the fuel pressure a little to lower the load some? Thanks!
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Old Apr 10, 2014 | 07:13 PM
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Are you running a return or returnless system?
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Old Apr 10, 2014 | 08:40 PM
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To me, "load" is about the motor MAP / cylinder air mass
and not about anything to do with fueling per se.

More pressure would let you run less duty cycle but you
are not close to having a problem there; it would also
perhaps make it more difficult to get idle fueling right,
if the injectors are oversized then you might run into
minimum pulse width problems as pressure goes higher.
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Old Apr 11, 2014 | 08:36 AM
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Originally Posted by jimmyblue
To me, "load" is about the motor MAP / cylinder air mass
and not about anything to do with fueling per se.

More pressure would let you run less duty cycle but you
are not close to having a problem there; it would also
perhaps make it more difficult to get idle fueling right,
if the injectors are oversized then you might run into
minimum pulse width problems as pressure goes higher.
I have another window on the fast hand held for MAP. It runs around 98-99 kpa with the induction I have now. I can look on the instructions to see if load is something other than injector related.
I was under the impression that increasing the fuel pressure would help atomization and help the injectors to go through their opening and closing cleaner and help the pulse width modulation. The injectors are a batch fire setup that maxes out around 550HP at 43 psi (that is the pressure Im running now). My engine should be around 530ish at the flywheel, so the injectors are probably not too big for the setup. There is only 4 injectors though, so the individual injectors are larger than a port injection setup injector would be. Off the top of my head I think I remember them as being 77s?
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Old Apr 11, 2014 | 08:37 AM
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Originally Posted by 89gmcs15
Are you running a return or returnless system?
Im running a return setup on mine. Its the only way the original EZ will work. Your 2.0 will work either way, Wont it?
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Old Apr 11, 2014 | 09:46 AM
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Originally Posted by newschool72
Im running a return setup on mine. Its the only way the original EZ will work. Your 2.0 will work either way, Wont it?
Yeah the 2.0 works with both but im running a return system. Ive seen the "load" gauge on mine too but without my driveshaft ive only played with the idle lol. This starts and idles better than the carb thats for sure! Ill report back with the load on mine after I get the driveshaft in and things finished this weekend.
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