Injectors. Everyone takes for granted that they work as advertised. Well guess what. They dont. More specifically they do not deliver fuel linearly from one end of the operating range to the other. None of them do, in fact, not even Injector Dynamics injectors do. But thankfully, new style injectors like the ones offered by Injector Dynamics are at least repeatable. That means they are always off of linear in the same way. That means that if you know how far off they are, you can use the ECU to "fix" or adjust them back to near linearty.
Therein lies the advantage of an Injector Dynamics injector. In fact it really is not the injector itself at all but rather the testing that goes into the injectors and their characterization that allows them to be used satisfactorily.
Case in point; Seen below is a plot made by Injector Dynamics showing the difference in flow rating for an ID2000 injector against a curve for the popular Indy 1600 or Bosch 160 injector everyone used until they knew better.
One may note a few differences in the "slope" of these two injectors as depicted here. First and most obvious but not really to be of concern is the increased flow rate for the ID2000 over the 1600. Not the point here.
What is quite curious is the slope of the 1600 at approximately 1.5 mS. Yes that is right, if you have these injectors, go look at your data at idle. It is right where 99.9 out of 100 engines idle pulsewidth wise. You can see the backwards response these injectors exhibit as PW is increased, flow actually goes downward before increasing at a somewhat linear rate. THIS IS WHY IT IS NEARLY IMPOSSIBLE TO MAKE AN ENGINE IDLE AND TAKE THROTTLE PROPERLY WITH INDY 1600s.
Next you will notice that there is a sort of staircase look to the top range of the injector at the upper right. This usually is the point where engines run into trouble. The ECU is assuming that the injector delivers fuel linearly. Therefore if it requests 3 percent less fuel, it expects the fuel flow to decrease by 3 percent. You can see that depending on where you are on the curve this may or may not be the case. Typical problems from using this type of injector would be random piston failure at high load for no apparent reason. Tune was not changed, been fine for a while and suddenly whamo, dead piston.
So ask yourself. You spent all the money on a MoTeC to have the most accurate engine management system you can afford on your specialized engine, why would you allow the link between these two to be an unknown varying piece of antique fuel delivering crap? If I told you there was a fuel pump available which had a fuel delivery curve like that listed above, would you use it just because that is what everyone always used before? Or would you use it because someone else uses it? Highly doubtful. My guess is you have done your homework and gone to the trouble to select the proper fuel pump and other components for the job. Now its time to step up and bridge that gap with a proper injector.
Injector Dynamics injectors are available through ST Consulting. For more information email shaneteck@yahoo.com or call 714.318.5845
Therein lies the advantage of an Injector Dynamics injector. In fact it really is not the injector itself at all but rather the testing that goes into the injectors and their characterization that allows them to be used satisfactorily.
Case in point; Seen below is a plot made by Injector Dynamics showing the difference in flow rating for an ID2000 injector against a curve for the popular Indy 1600 or Bosch 160 injector everyone used until they knew better.
One may note a few differences in the "slope" of these two injectors as depicted here. First and most obvious but not really to be of concern is the increased flow rate for the ID2000 over the 1600. Not the point here.
What is quite curious is the slope of the 1600 at approximately 1.5 mS. Yes that is right, if you have these injectors, go look at your data at idle. It is right where 99.9 out of 100 engines idle pulsewidth wise. You can see the backwards response these injectors exhibit as PW is increased, flow actually goes downward before increasing at a somewhat linear rate. THIS IS WHY IT IS NEARLY IMPOSSIBLE TO MAKE AN ENGINE IDLE AND TAKE THROTTLE PROPERLY WITH INDY 1600s.
Next you will notice that there is a sort of staircase look to the top range of the injector at the upper right. This usually is the point where engines run into trouble. The ECU is assuming that the injector delivers fuel linearly. Therefore if it requests 3 percent less fuel, it expects the fuel flow to decrease by 3 percent. You can see that depending on where you are on the curve this may or may not be the case. Typical problems from using this type of injector would be random piston failure at high load for no apparent reason. Tune was not changed, been fine for a while and suddenly whamo, dead piston.
So ask yourself. You spent all the money on a MoTeC to have the most accurate engine management system you can afford on your specialized engine, why would you allow the link between these two to be an unknown varying piece of antique fuel delivering crap? If I told you there was a fuel pump available which had a fuel delivery curve like that listed above, would you use it just because that is what everyone always used before? Or would you use it because someone else uses it? Highly doubtful. My guess is you have done your homework and gone to the trouble to select the proper fuel pump and other components for the job. Now its time to step up and bridge that gap with a proper injector.
Injector Dynamics injectors are available through ST Consulting. For more information email shaneteck@yahoo.com or call 714.318.5845
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