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Unread 02-18-2009, 08:50 AM
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Also there is a great conversation about fuel lines over at Lextreme.com They discuss a lot of things and there is some advice with a lot of experience behind it but without the attitude. These are good people. Always think and learn for yourself but here is a good start for everyone who is continuously working to understand fuel injection:
Here is the basics of why it wont work.
Injectors in EFI engines work by opening and closing (pulsing) and the period of time that they open and close for is the duty cycle.
Your engine management system whether factory or aftermarket needs to be able to calculate the amount of fuel going into the engine to keep the AFR's correct.
It manages this by knowing how much fuel is in one pulse of the injector and it relies on that pulse always containing the same amount of fuel.
It measures the air volume by either map or maf and then matches the fuel requirement to get the right ratios.
Then the O2 sensor relays back how well the operation went.
If you don't maintain constant fuel pressure then that pulse by the injector may contain more or less fuel than the management system is expecting.
It is the variation that is the problem, so no it wont work.
There are do's and donts with efi and this is definately a dont.
Factory management systems can generally cope with a few changes to the fuel system for example a slight increase in injector size.
Now each pulse contains more fuel because of the larger orrifice in the bigger injector but again it is constant.
This is when the system will relearn and trim the duty cycle until it once again has acceptable AFR's.
The same can be said for increasing fuel pressure to the injectors.
If the injectors see higher pressure then they will deliver more fuel per pulse, but once again it is constant and the management system will compensate for it again by trimming duty cycle.
Cheers
tRev
Have a read about some fuel issues as related with aftermarket engine management systems. http://www.lextreme.com/forums/showthread.php?t=4629
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