Injectors?

driller

driller

El Presidente
Staff member
Ford Racing Performance Parts # M-9593-A302 (24lb/hr - Type EV1 - 11-18 ohms impedance)

The number on the one side of the injectors, is 280150759

on the other side is: E8TE-B1C

Will these work on the '93 Mark VIII?

If so, will a tune be needed changing from stock injectors?
 
RE: Injectors?

I'm working on an intake swap. I want to make it simply plug and play and not have to swap out injectors, IACV, TPS, etc...

I don't know the history of the injectors on that particular intake now. I have a line on these I posted about and they are apparently flow matched and were used very little.

I guess maybe my question is... is a 24# FRPP injector equivalent to a 24# FLM injector? Will the tune change if I swap?
 
RE: Injectors?

Depends on exactly what "flow matched" means.

If they're the same size injector, just drive it around in closed loop (no WOT) for a while and let the fuel trims adjust, and you should be fine.

If you're going to buy injectors, though, why not go big? Then you're ready for a blower or nitrous later on.
 
RE: Injectors?

[div class="dcquote"][strong]Quote[/strong]
If you're going to buy injectors, though, why not go big? Then you're ready for a blower or nitrous later on.
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Would they(bigger injectors) trim out as well? My calculations tell me the stock 24 pounders will support anything you'd want on the stock block as far as a blower or nitrous power adder goes.

Or am I wrong?
 
RE: Injectors?

[div class="dcquote"][strong]Quote[/strong]
[div class="dcquote"][strong]Quote[/strong]If you're going to buy injectors, though, why not go big? Then you're ready for a blower or nitrous later on.[/div]Would they(bigger injectors) trim out as well? My calculations tell me the stock 24 pounders will support anything you'd want on the stock block as far as a blower or nitrous power adder goes. Or am I wrong?
[/div]

Can they (24lbs) support 400rwhp safely ? That's definitely doable with the stock block. I am mad at myself I didn't up the boost when the vortech still on the car. :(

I would at least go with 42s. But the fuel trims will definitely have to be changed in the ECU.
 
RE: Injectors?

I plan on maxxing out 30 lb injectors on a stock block. If the 24's will do 400 HP, the 30's will do 500. A 150 dry shot of NOS should be truth serum (Judge Judy style) on a stock '94 block with a few breathing mods.

mark
 
RE: Injectors?

[div class="dcquote"][strong]Quote[/strong]
Can they (24lbs) support 400rwhp safely ? That's definitely doable with the stock block.
[/div]

400 RWHP on a stock block?! Wouldn't that be about 500 HP at the crank? On stock rotating elements? :eek: That's quite a bit better than I originally had thought.

I'd be happy with 350 RWHP(445 BHP). :9

Back to the math. I guess 'safely' is a relative term. Most likely the best definition is a max duty cycle of 85%. The BSFC(Brake Specific Fuel Consumption) calculated for a stock naturally aspirated engine is 0.58 pounds per hour per HP.

Therefore... (HP*BSFC)/(# cyl. * Duty Cycle) = (445*0.58)/(8*0.85) = 38.18

But all that is at stock fuel pressure. According to different online calculators, 24 pound injectors at 70 psi CAN flow enough for 445 BHP (actually delivering 32 pounds per hour?). So I guess IF one plans on a significant power adder, upgrading the injectors would be a must.

But back to my original question, I CAN use the FRRP 24# injectors and expect the fuel trim to be handled by the PCM by running closed loop and avoiding WOT for a while.
 
RE: Injectors?

YES.

Don't fall into the same trap guys used to with carburetors. No matter how many people told inexperienced car owners 650 CFM, vacuum secondaries, properly jetted, was more than enough carb for any streetable engine, they always immediately believed the one lunatic who told them an 1150 Dominator would be just the cat's ass.

Unless you're planning on going totally insane with your car, stick with the 24s. If, some time in the future, you do find the engine goes a little hungry, play with fuel pressures (within reason).
 
RE: Injectors?

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If, some time in the future, you do find the engine goes a little hungry, play with fuel pressures (within reason).
[/div]

That brings up a couple good questions.

What fuel pressue is 'within reason'?

Is there a way on a EEC IV to determine what the duty cycle on the injectors is? Tazzo used to have a fuel injector duty cycle readout device.
 
RE: Injectors?

Once again, bigger is not always better.

Now I'm talking about your factory fuel pump. It's capable of making 100 Psi all day. Block off your return line while you have a pressure gauge hooked up and see. The car probably won't run...

Don't be afraid to experiment with pressures up to~ 60 psi. If you need more than that to prevent a WOT lean condition, maybe you should have gone with bigger injectors.

Remember: high flow injectors or using high pressure to increase volume really can only benefit at WOT, when the system reverts to open loop. At any other time (except for cold start) the PCM will take control of delivery and trim fuel as best it can. If it has to exceed 20%(+ or-) Short Fuel Trim or 10%(+ or-) Long Fuel trim, it'll trigger the MIL light and set codes.

I don't know about measuring duty cycle per se. The PCM displays its information to Ford's datalogging tools as Milliseconds "on" time. It's what I'm used to when I'm analyzing fuel concerns. I'm sure this could be converted arithmetically to duty cycle easily enough.

For Example:
-a 4.6 Mustang at idle, with 0% Fuel Trim, the PCM pulses the injectors at~ 8 milliseconds.
-at ~92% TP (just before the PCM switches to WOT open loop),it pulses them at ~ 240 milliseconds.

You do the math; they're hardly at full capability.
 
RE: Injectors?

My wife was hanging over my shoulder last night, "reminding" me about a restaurant reservation...

I'm not sure how clear I was.

First of all, keep in mind that those "on" times are in relation to a second, so move the decimals over and you've got a HYPOTHETICAL duty cycle. See how (comparatively) short on is to off? The physical limitations of fuel flow through an open (100% duty cycle) injector are hardly an issue under most circumstances.

Hypothetical?

Please, you must understand that those numbers in my previous post were what I have seen in my day-to-day work. At best, they are simply figures in a very large ballpark.

You'll be hard-pressed to find documentation anywhere as to what "correct" or "normal" pulse times are, and if you do, be highly suspicious. There are just too many variables used by the PCM to make its delivery calculations.
-Open or Closed Loop?
-ECT
-IAT
-MAF
-TP
-O2s/Catalyst Monitors(OBDII)
-What's the trans doing?
-How far has the PCM advanced injector timing at the moment being discussed?
-Where has it put ignition timing?
-Is the stereo pumping? The PCM even accounts for things as minor as electrical/alternator load at any given time.
-A/C on?
Etc..etc..etc..

So why would you ever want bigger injectors?

WOT Open Loop.

Let's talk those hypothetical numbers:
Somewhere, a programmer, working with the driveline engineers, decided that,...say... a 24lb injector opening at...I don't know, let's say... 500mS would provide exactly the correct amount of fuel to an engine at WOT. He's a programming engineer, which means he's better than God. He knows he can't be wrong, so why would the PCM need O2 feedback to correct him? WOT only occurs in short bursts, right? Hence WOT Open Loop. (There's many other reasons, too, but bear with me).

You now take your car and change cams, or add a blower, whatever, but it's something so radical that the pre-programmed "24lb at 500mS" cannot supply your new requirements. Even tuning a chip to increase WOT pulse width can't do it. Only now do you have no choice but to push the fuel through a bigger hole.

If high flow injectors are not really required, the PCM might be able to correct with negative fuel trims in Closed Loop, but at WOT, fuel is delivered at a preprogrammed pulse. If the hole is bigger, the system goes too rich, loses power, and you've caused more harm than good.
You may be able to compensate for your mistake with chip programming and a different MAF calibrated to the new injectors, but what's the point?

The end result? You've put a half-dozen apples in a bag and taken six back out!
 
RE: Injectors?

Okie dokie lots of stuff in this thread.

Truth be told:
400rwhp on one setup is not 400rwhp on another.

400rwhp on Nitrous or turbocharged is a totally different power level than 400 rwhp supercharged. You can count on at least 55rwhp being sucked away with an S strim SC 60-70 with a T trim and 100-150+ with a novi2K depending on how hard you are running it.

First thing to determine is which power adder are you planning on going with.

I know for a FACT you can spray a dry 175shot with an NOS kit with stock 24#/hr injectors with ease on stock parts. If i had bigger solenoids on my kit I would spray more. The fuel pressure goes up to 82psi on a 175 shot.

When I get my red car Twin turbo'd here in a little bit I think i can make 475rwhp on stock internals all day long. If I had it supercharged no way would I go past 425 on stock internals in a mark VIII.

High quality Siemans Deka injectors can operate at 90-100psi base fuel pressure. The stock bosch injectors should operate no problem at 75psi base fuel pressure. While your injectors will not have a problem with this, your fuel pump sure will. Once you increase the PSI on the pump the pump rate decreases tremendously! Seach around on the aeromotive or weldon website if you are more interested about just how much it affects pumps. It is suprising.

I would presume that IF you had enough pump you could support 500rwhp on 24#/hr injectors. This being the case if you had someone that could tune well.
 
RE: Injectors?

And JP there is no reason to spend money on flow matched 24# inejctors. When you get up to 72, 83, 96, or esp 150#/hr yes flow matching is important as a litle percentage of variance translates into a LOT of fuel.
 
RE: Injectors?

[div class="dcquote"][strong]Quote[/strong]
And JP there is no reason to spend money on flow matched 24# inejctors. When you get up to 72, 83, 96, or esp 150#/hr yes flow matching is important as a litle percentage of variance translates into a LOT of fuel.
[/div]

I see your point. I need to look at racing these cars as I do items at work. While a steel price difference of 3 cents per pound may not sound like a lot, it sure is when you're talking over 3,600 TONS per year. :eek:

I see your points as well as XXX RWHP nitrous/turbo vs. XXX RWHP supercharged. ;)
 
RE: Injectors?

exactly. BTW when are you headed back through town here? I got a pile of parts with your name on it.
 
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