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Discussion Starter #1
I have an understanting how they work, I think. BUt im unclear how injectors can provide more horsepower. Does it flow better while maintaining a correct spray pattern with the same pulse with from the pump?? Or do the factory injectors limit the flow of the pump before the limits of the pump are reached??

Thanks for the insite!
 

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The spray pattern is matched to the piston bowl ,when the spray pattern is changed you loose power becuause the fuel is moved to the outside the bowl " cold fire " but the other side is the the pistons can be burnt.

The injector is there to hold back pressure and to spray the fuel @ a given cycle. They make more power becuase of the size,#'s and how smooth the holes are.

On a Ve the injector being fired the others must hold the pressure and if weak spring is dripping fuel the power is going to be down as well as the smoke will be higher.This is why a set of weak used / in need of rebuilt injectors is needed because they change how a engine is running,power and fuel mileage.

Scott
 

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Discussion Starter #4
So when the injector is rated, (lets call them 60hp) what does that mean? I thought on a VE pump fuel was directed to a specific injector. Is it holding closed against a small amount of residual pressure in the line??? And how does a bigger injector make more power when the pump stroke determines how much volume goes to the injector?? Im sure these questions are simple and obvious so im sorry to even ask.

thanks,
 

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A bigger hole allows more fuel to inject as the needle lifts off the seat.Without turning the max fuel up on the pump theres little gain.Once your fuel rate is up then your injectors can do work.
 

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Being that the pump is positive displacement I've never really understood how the DV or the injectors can have that much of an effect on power either.

I think that there is a ceratain elasticity in the line and micro amounts of air in the fuel that might allow a bigger injector to dump it's load in the cylinder faster and allow slightly more fuel but ultimatley it is the pump that controls the fuel volume, not the DV's and the injectors. There is a point I'm sure that you just can't push more fuel through small holes. I would think that you are going to destroy your pump at that point though.

Maybe there is a lot more leakage around the pump plungers than I think....

I have never seen a good explination of this yet. Might be because there is a lot of money being made on aftermarket injectors and DV's....
 

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Discussion Starter #7
As I do more research, Im wondering if bigger injectors are able to hold more pressure so that when they fire the associated pressure drop atomizes the fuel more completely and shortens the duration of the injection, Increasing the impulse on the piston. Maybe. or im just rationalizing why something is already done.
 

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Discussion Starter #9
AHHH, So they flow more in a given duration. So turning your pump up with the stock injectors actually lengthens the Pulse time of the injection, and by going with a bigger injector you can get your time back down.
 
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