Engine Injector choice questions- 1987 fox 5.0 AOD

[Vulpes5.0]

I'm curious what size injectors I should run on my car. Currently have 19 lb injectors and it runs, but I need to do a MAF conversion and get bigger injectors to accommodate the new power and idle/dying issues associated with it. (there's more to these issues but i do still need to upgrade injectors, they're worn out)
The mods on the car so far are:

BBK shorty headers and X-pipe
Explorer upper and lower intake
GT40 cylinder heads
Trick flow stage 1 cam
EGR delete, smog pump delete
SVE radiator


I'm thinking 30 lb injectors, but I don't have much of an idea of the power figure this car will make. maybe a little over 300? I do plan to upgrade more and dabble in forced induction, small turbo, so I don't want to under-build. At the same time, I don't want to over-build either, I've heard that people's cars don't run right if the injectors are not at a reasonable duty cycle based on lower power numbers than anticipated. Just looking for some power figures, tips, suggestions, thank you for the help!

Side note- i have a 19lb MAF from BBK i bought second hand. Any way it can be recalibrated without spending 150? by that point i may as well just buy new and sell the 19lb

 

[Wayne Waldrep]

One of my engines back when did 325hp to the tires using 24# injectors. They were at 85% duty cycle. I had 30# injectors when I built it but my engine builder didn't want to use those. He suggested selling and going with 24s to better match my combo. He's an engine genius in my book so I did what he said and the engine was awesome. I don't think you can get an injector for now that will match good but also be good later for a turbo setup. That's just my thoughts though. The digital tuning guys know their stuff so I'd listen to them for sure.

 

[JD1964]

Do you have a wideband O2? If not I recommend putting one on before you make any injector changes. Or at least make the wideband part of the upgrades. But, if you put the wideband on first you can run it full out and see if the 19's are not keeping up.

 

[Vulpes5.0]

Do you have a wideband O2? If not I recommend putting one on before you make any injector changes. Or at least make the wideband part of the upgrades. But, if you put the wideband on first you can run it full out and see if the 19's are not keeping up.

Not yet, but my o2 sensors were going to be replaced anyway, they're the factory ones, and they have quite the large ticker of miles on them.
widebands just plug right in? any recommendations?

 

[General karthief]

Keep 19 lbs injectors in it.
and if you are having issues with it now adding stuff to it without fixing the problem will make matters worse.

 

[Vulpes5.0]

Keep 19 lbs injectors in it.
and if you are having issues with it now adding stuff to it without fixing the problem will make matters worse.

Would it be wise to convert to MAF as of right now? i have everything i need, and it's calibrated to 19s

 

[JD1964]

Not yet, but my o2 sensors were going to be replaced anyway, they're the factory ones, and they have quite the large ticker of miles on them.
widebands just plug right in? any recommendations?

For a wideband setup you'll need to cut a hole in the exhaust pipe down stream of the headers and weld a bung in to accept a dedicated O2 sensor for the wideband.

I'm using PLX brand with Bosch sensor. It's been flawless for me.

https://www.plxdevices.com/PLX-Wideband-O2-Air-Fuel-Ratio-Sensor-Modules-Gauges-s/125.htm

 

[Vulpes5.0]

For a wideband setup you'll need to cut a hole in the exhaust pipe down stream of the headers and weld a bung in to accept a dedicated O2 sensor for the wideband.

I'm using PLX brand with Bosch sensor. It's been flawless for me.

https://www.plxdevices.com/PLX-Wideband-O2-Air-Fuel-Ratio-Sensor-Modules-Gauges-s/125.htm

Oh so these are separate from the computer's o2 sensors? like something i connect a gauge to to show rich/lean? i think I've seen that used in carbed applications before

 

[a91what]

I would never purchase or install anything smaller than a 42lb injector in anything... a good tuner will be able to make use of almost any injector up to 80lb.

 

[JD1964]

Yes, the O2 widenband setups are stand alone from the Foxbody factory electronics. If you like tinkering and tuning, you really should get this first.

You could do the MAF upgrade and keep the stock 19's for starters. And, a 70mm Ford maf would be a cheaper way to get started. These are calibrated for the 19's. They work good. If your 19's turn out to be a tad lean, you can crank up the fuel pressure a few lbs and squeeze more out of them.

These ford cars have the 70mm 19lb maf that works good in maf equipped Foxbody cars

1995-94 Mustang 3.8L F2VF-12B579-A2A,
1994-92 Crown Victoria 4.6L F2VF-12B579-A2A,
1995-94 Mustang, Mustang Cobra 5.0L F2VF-12B579-A2A,
1994-92 Town Car 4.6L F2VF-12B579-A2A,
1994-92 Grand Marquis 4.6L F2VF-12B579-A2A,

 

[JD1964]

I would never purchase or install anything smaller than a 42lb injector in anything... a good tuner will be able to make use of almost any injector up to 80lb.

I can't disagree with this but it costs more, thats for sure. Because you have to buy more expensive stuff through and through

 

[JD1964]

....and pay the tuner

I had dumb luck and have not paid a tuner one penny, except for the dyno runs, and the tuner said, "dont change a thing"

My 30lb'ers are maxed and I can fine tune by bumping FP up or down. Seriously though, dumb luck on my part but its works great for me.

 

[Vulpes5.0]

Yes, the O2 widenband setups are stand alone from the Foxbody factory electronics. If you like tinkering and tuning, you really should get this first.

You could do the MAF upgrade and keep the stock 19's for starters. And, a 70mm Ford maf would be a cheaper way to get started. These are calibrated for the 19's. They work good. If your 19's turn out to be a tad lean, you can crank up the fuel pressure a few lbs and squeeze more out of them.

These ford cars have the 70mm 19lb maf that works good in maf equipped Foxbody cars

1995-94 Mustang 3.8L F2VF-12B579-A2A,
1994-92 Crown Victoria 4.6L F2VF-12B579-A2A,
1995-94 Mustang, Mustang Cobra 5.0L F2VF-12B579-A2A,
1994-92 Town Car 4.6L F2VF-12B579-A2A,
1994-92 Grand Marquis 4.6L F2VF-12B579-A2A,

I already have a BBK 19 lb MAF, along with the conversion harness that i was planning on using. I suppose I'll start there. what's your setup looking like to max out 30 lb injectors? I'm thinking it'll be the right setup for me eventually, but i don't want to have to tune my car, i want to go factory ECU unless absolutely necessary

 

[Mustang5L5]

Speed density plus TFS1 cam?

I’d convert to mass air as soon as you can. As for what injector? I’d go with a 24# and good calibrated MAF and call it a day

Let’s not over complicate things, that combos been run a million times. Pretty simple really

 

[Mustang5L5]

Just to add... TFS1 is notorious for low RPM bucking. This can be tuned out.

It’s also a cam that loves to be at or above 3k RpM. Not really ideal for an AOD car. Hopefully you have 3.73s or 4.10s.

 

[JD1964]

On my setup its the supercharger at 10psi that maxes out the 30’s

 

[Vulpes5.0]

Just to add... TFS1 is notorious for low RPM bucking. This can be tuned out.

It’s also a cam that loves to be at or above 3k RpM. Not really ideal for an AOD car. Hopefully you have 3.73s or 4.10s.

Oh, I didn't know any of that... oops. Might have to invest in some gears. we'll see.

 

[General karthief]

but I need to do a MAF conversion and get bigger injectors to accommodate the new power and idle/dying issues associated with it. (there's more to these issues but i do still need to upgrade injectors, they're worn out)

Ok, you already have idle/stall issues, doing all this will NOT fix this, it has to run right before adding modifications. You will likely make it worse and more difficult to fix.
Just my thoughts, carry on.

 

[Vulpes5.0]

Ok, you already have idle/stall issues, doing all this will NOT fix this, it has to run right before adding modifications. You will likely make it worse and more difficult to fix.
Just my thoughts, carry on.

I need to set the idle and I'm positive i have a vacuum leak, probably at my PCV valve, I can even hear it.
I just have to weekend warrior my car because I'm so busy so i spend a lot of my time speculating on here instead, and I'm sorry that bleeds off onto y'all lol

 

[Vulpes5.0]

Just to add... TFS1 is notorious for low RPM bucking. This can be tuned out.

It’s also a cam that loves to be at or above 3k RpM. Not really ideal for an AOD car. Hopefully you have 3.73s or 4.10s.

When you say tuned out- does this mean standalone ECU or a chip of sorts? I know standalones are very expensive, not sure about chips.
Also- Could I run 30 pound injectors theoretically without issue as long as i have the right MAF? i figure an extra 20-30 dollars over 24 pound injectors would be worth it just for the extra wiggle room down the road. I just want to be sure the A9P won't nuke itself when i upgrade injectors too much