Which injectors do I need?

I've got a set of FMS 24lb injectors that I took off my car when I swapped the 306 for a 347. I'm running 30s now. They have been in my shop for the last three years and I have no use for them.

Dont forget your going to need a new MAF with those injectors :]

what mods do you have?

johnny_munyak said:

I realize that the MAF will not longer match.....however the stock MAF on a 95 GT is a 70 MM unit....but calibrated for 19lber. A custom chip can recalibrate the stock MAF for useage with 24lbers.

Or am I missing something?

Click to expand...

Well ... It may sound like I'm splitting hairs
BUT
No Ford OEM meter is caled for ANY particular size of inj

Also ... A tuning interface or chip does not recal the meter

I won't go into a long winded or boring bunch of details
but
Just to keep things in the ballpark of being kinda accurate

I will say ... From a tuning perspective ............

If your mods don't generate more airflow than the OEM meter's limit
then
You could use 24's or 30's with that OEM meter

The data manipulation is done in the pcm ... don't ya see

Now ... if you wanted to try and get by without a tune

You could go with the Cheat Method which is used by Aftermarket
Meter Manufactures

That method is focused around using an electronic (ProM) or mechanical
(C&L) method of tricking the pcm about the true amount of air flowing
through the meter

You decide how much fuel you will need (inj size)
then
You select a meter that has been "caled" to that particular size of inj

The cheat method works pretty good with 24's ... no guarantees
but
When you move up to 30's or larger

You got a pretty good chance of issues at idle and cruise conditions
cause
The larger size inj's will push out too much fuel

Also ... Cheat Method really hoses up the 94-95 pcm load factor's
BUT
I promised not to go into all that kinda stuff ... Didn't I

Now ... That we've kinda sorta set the record straight

Like Jinx said ... "How could we answer your Q with any kind of
intelligence if we don't know anything about your mods or plans
for your combo"

I'm done now

Grady

WOW Grady saying that I said something important is like a car god saying I'm the greatest gear head ever.


I am happy that he mentioned me though

hmmm I would think maybe going to 30's would be better but Grady would be the one to answer that

Kinda short on time tonight
so
I'll just touch on the basic ballpark kinda answer

If one was gonna try and get by without a tune on such a combo

They would most lilely go 24's and use an afpr

If one was gonna custom tune .......
My first choice would be 30's for MANY reasons
but
I'll just hit the important ones

1) You NEVER wanna go lean under heavy load
2) You will be tuning at OEM pressure
therefore
30's act smaller than most peeps relate to when using elevated pressures
3) You can easily tune out fuel at low pulse width conditons like idle & cruise
4) Last but not least ....
Many ... I repeat ... Many ... have seen 24's peter out sooner than they
thought on h/c/i combos ... therefore ... 30's give you room to grow and
allow you to know for sure you are covered under all condtions

As always ... You go the route based on your application :Word:

Gotta Go

Grady