I'm going to change the injectors on one of my cars as they are just about maxed out.
They are 241cc (@ 3Bar) x 4 but installed and running @3.5Bar
I want to change then to some I have
359cc x 4 and reduce the fuel pressure to 3.0Bar
I'm thinking that the fuel pressure reduction would need an increase in injector duration of 7% to compensate.
And the increased injector size would require a 49% reduction in duration.
Therefore a total duration reduction of 42% across the map would leave me with the same fuel into the engine.
Does that sound anything like right?
Calculations for new injectors
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Re: Calculations for new injectors
Just give it a try and scale it up/down until idle AFR's are close to where they were. But you would still need to check everything under load, dont take it for granted.
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Re: Calculations for new injectors
Yeh, but I'd like to be a bit more scientific about it
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Re: Calculations for new injectors
Science only takes you so far....after that, the force is required...( or some guessing )
And injector behaviour, dead times etc....can all add variables as to how things act under load. Although if all the data is correct...they differences should be reduced.
And injector behaviour, dead times etc....can all add variables as to how things act under load. Although if all the data is correct...they differences should be reduced.
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Re: Calculations for new injectors
There are a couple of calculators here that should help:
http://www.deatschwerks.com/fuel-calculators
http://www.deatschwerks.com/fuel-calculators