Upgraded fuel injectors

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DPDISXR4Ti
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Re: Upgraded fuel injectors

Post by DPDISXR4Ti »

brokencase wrote: Sun Nov 24, 2019 7:48 pm From which junkyard vehicle did you pull the 4 hole 14lb injectors from? Some 6 cylinder Ford from the late 90's I suppose?
Good question. I had considered starting a donor list, and so now I will. I've grabbed some from '91 - '93 2.3 Mustangs and '95/6 F-150 4.9's, although the later should be something slightly less than 14pph. Other possible donors include:

'90 - '92 Ford Probe V6 Mazda MX-6
'94 - '98 V6 Mustang

2001+ 3L Ranger injectors are 14pph but EV6, so a new wiring harness is required, but they are the later "pencil" style injectors.
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Re: Upgraded fuel injectors

Post by brokencase »

Here's a thought....

If the new injectors have better atomization, then maybe you could flip the phases of the injector banks so that they fire when the valves are open?

Maybe the injectors firing against the closed valve is why the Scorpio intake manifold gets so dirty all the time.
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Re: Upgraded fuel injectors

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brokencase wrote: Tue Nov 26, 2019 12:07 pm If the new injectors have better atomization, then maybe you could flip the phases of the injector banks so that they fire when the valves are open?
So you're talking SEFI? That would require a revised wiring harness and a PCM which could support that. Entirely possible, but now you're talking about a much bigger project.

Ironically enough, as I was pulling two sets of 14pph EV6 injectors from a 2003 Mazda B3000 and a 2008 Ranger 3L last week the thought occurred to me that it might be worth considering running the PCM and MAF from this truck. You'd probably want to pull pretty much the whole harness and all the attached sensors. But it might require the ability to modify the calibration, and I don't know if there's any knowledge-base out there on this one.

For now, I'll try modifying a spare FI harness for the EV6 injectors and take it from there.
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Re: Upgraded fuel injectors

Post by brokencase »

No, I'm not talking about converting to sequential or MAF.

The article that I posted indicated that the original Scorpio setup bank fires three injectors at a time and that (on average) the injectors fire when the intake valves are CLOSED.

What I'm saying is to try the experiment where you swap the banks (via the harness). That should then fire the injectors when (on average) the intake valves are OPEN.

In the original configuration they were firing the single pintel injectors against the closed valve to get better atomization. The newer multi-hole injectors have better atomization. Maybe its no longer needed.

No big gains expected other than smoother idle and easier starting.

If you want to do a MAF conversion then the way to do that is with the 89 MAF Ranger ECM and associated items. At least one Scorpio owner has done this. I'm not sure if that one is sequential though. Not sure it is worth the effort either.

I think folks make too much out of MAF vs. MAP. I believe you can do performance improvements with MAP (like headers and porting, etc)
and still get the MAP arrangement to work "good enough" either by sizing injectors or playing with fuel pressure (or other means).
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