How does one know...

toyman

10 Year Member
Jul 19, 2007
1,944
54
79
Vernon BC
From my sig you can see that I have a 2.1 KB installed :D

I'm using a FMU that makes everything work in the fuel department :rolleyes:

However, since I've installed a fuel pressure gauge I'm wondering if this is a long term satisfactory solution given the fact that the fuel pressure rises to 78 psi at WOT :shock:

So how does one know what to change :shrug:

From reading the various threads it appears that one can change the fuel pump to a higher rate without any serious consequences :shrug:

So I've purchased a 190 lph pump as a start (that's double the stock isn't it?) :nice:

Next I'm looking at the injectors. Again it appears that these can be changed at will but I wonder :shrug:

I'm considering purchasing a set of Ford Racing 30 lb injectors :shrug:

Will my stock computer initially be able to handle these changes with the stock MAF or does the MAF have to be matched to the injectors :shrug:

Getting a dyno tune presents some difficulty as none are near where I live :(

So, how does one know what to do :shrug:
 
Gotta have the MAF matched to the injectors (this is not the way it works technically but we don't want to confuse the thread). If you change the injectors to a different size, the MAF transfer curve needs to be adapted (either with a 'calibrated' MAF or via a tune.

If you like to tinker, I'm sure the guys are goin to suggest to use big squirters, an LMAF and an RT. Then you can dial it in perfect, rather than having stuff that should work but having no way of adjusting the bugs out.

You can do a lot with the trans (Wes is great with assistance!) with an RT as well.

Good luck.
 
Here is what I'd do if I was you
and
Seeking the knowledge you ask about :D

First thing is ... Don't buy anything else :nono:
until
You take advantage of peeps knowledge on these boards that have
successfully done what you seek to do :Word:

You can find a few on this forum :shrug:
but
I'd focus in on the power adder forums :nice:

I assure you ...
You'll find plenty of reading material to educate yourself ;)
The fuel needs of a blown street combo have been throughly thrashed :crazy:

If you wanna tune as Ford did with a FMU-less setup :banana:

In a nutshell ...

You go with a big in tank pump & maybe an in line pump as well
You go with inj's of 42lbs or maybe even larger
You go with a meter that will handle the blower's additional airflow
You go with a way to adjust the pcm to make it all come together

The ability to adjust things with the pcm is gonna be W A Y more
accurate than that Mickey Mouse mechanical FMU method :Word:

No ... You won't be able to go with a meter caled for 42's
and matching inj's without SOME drivability issues with
OEM pcm values :bang:

Grady
 
Here is what I'd do if I was you
and
Seeking the knowledge you ask about :D

First thing is ... Don't buy anything else :nono:
until
You take advantage of peeps knowledge on these boards that have
successfully done what you seek to do :Word:

You can find a few on this forum :shrug:
but
I'd focus in on the power adder forums :nice:

I assure you ...
You'll find plenty of reading material to educate yourself ;)
The fuel needs of a blown street combo have been throughly thrashed :crazy:

If you wanna tune as Ford did with a FMU-less setup :banana:

In a nutshell ...

You go with a big in tank pump & maybe an in line pump as well
You go with inj's of 42lbs or maybe even larger
You go with a meter that will handle the blower's additional airflow
You go with a way to adjust the pcm to make it all come together

The ability to adjust things with the pcm is gonna be W A Y more
accurate than that Mickey Mouse mechanical FMU method :Word:

No ... You won't be able to go with a meter caled for 42's
and matching inj's without SOME drivability issues with
OEM pcm values :bang:

Grady


Thanks Grady

I've been reading the power adder forums and it has lead me to further confusion :shrug:

I guess the thinking is why not go with the largest and tune for what you have today, thinking that boost is addictive :D

And while I agree that boost is addictive I'm thinking that at my age I should recognize my limits :rolleyes:

So I'm thinking that if I want to get rid of the FMU what do I need to do the job if I'm not going to go wild in the future :shrug:

Everything seems to point to getting a RT tuner (Tweecer?) no matter what I decide to do unless I have ready access to a local tuner :shrug:

I considered that a few years ago when I could have bought the Tweecer RT for about $250 :(

Since the stang is now garaged for the winter I have time to ponder the ponderables ;)
 
After rounding up suitable parts to replace the FMU .....

You'll have to make the decision to Self or Pro Tune :shrug:

Lets break it down to money & ability :D

MONEY :)

Self tuning with a Tweecer will set you back at or a bit over 1 Grand
550 interface
200-400 laptop
200-300 wide band
50-100 misc software

You can get a Pro to do it for less

ABILITY :)

A Pro should have the ability
but
You'd be wise to get references

You as the tuner will take some time :shrug:
cause
You basically teach yourself as you go along :D

Here is where I would say your choice in forced induction can be a
bit of a disadvantage cause A forced combo is much more critical of
mistakes or misunderstandings than a NA combo :Word:

I'm not saying you can't learn to tune your forced Stang :nono:

I am saying you'll need to be focused and careful ... thats all ;)

I don't see how anybody can tell you if :scratch:
You should ... or ... should not ... Self Tune

You can dig up old threads where myself and others have tried to
describe what its like :crazy:

I some how think most peeps who have taken to it :nice:
and
Have found satisfaction from the whole process :banana:

Well ... they just know before they even get started :D

Its Gonna Be A Hoot ;)

btw ... there is some basic Tweecer self tuning stuff on my site :shrug:
its done with older software
but
the info is accurate and still valid :shrug:

Maybe you can get some insight from that stuff :shrug:

Grady
 
Okay let's take this one step at a time :)

Rounding up suitable parts :scratch:

That's where I am looking for input/advice :shrug:

We know that the fuel pump, injectors anf MAF meter need to be changed but it's here where one gets a wide range of opinion :crazy:

So, if I'm going to keep boost in the 6-8 psi range on an otherwise stock engine my take on the various posts would indicate that a 190 lph pump, 30/36 lb inj and a matched MAF meter should, with a tune, work well together :cool:

By working well together I mean that all the componets are not being pushed to their operating limits if that makes sense :shrug:

Or are we dealing with matters where bigger is generally better :shrug:

If I can help it I would just like to do the job once :bang:

We do know that with the current setup the FMU is forcing the FP and injectors to work in a way they were not designed for :eek:
 
Okay let's take this one step at a time :)

Rounding up suitable parts :scratch:

That's where I am looking for input/advice :shrug:

We know that the fuel pump, injectors anf MAF meter need to be changed but it's here where one gets a wide range of opinion :crazy:

So, if I'm going to keep boost in the 6-8 psi range on an otherwise stock engine my take on the various posts would indicate that a 190 lph pump, 30/36 lb inj and a matched MAF meter should, with a tune, work well together :cool:

By working well together I mean that all the componets are not being pushed to their operating limits if that makes sense :shrug:

Or are we dealing with matters where bigger is generally better :shrug:

If I can help it I would just like to do the job once :bang:

We do know that with the current setup the FMU is forcing the FP and injectors to work in a way they were not designed for :eek:

I'll be happy to give my thoughts and input on each Q or concern
but
Its gonna have to be later this afternoon :D

Grady
 
Knowing that forced induction engines need more fuel than your standard na engine combo it's better to go a little bigger than needed on your fuel system. Here's what I would recomend for any basic forced induction combo as a bare minimum.

42lb. fuel injectors
255lph high pressure fuel pump (walbro GSS340)
80mm or larger maf cal'ed for 42's or a 90mm lightning maf.
Some sort of tuning everything.

I wouldn't run this setup without tuning because even if the engine seems to be running fine it doesn't mean that it is safe timing and A/F ratio wise. The lightning maf will also have to have a custom tune in order to work.

The 36lb. injectors and 190lph fuel pump might work but they will be slightly taxed and I would rather know that these components are going to be able to handle the fuel requirements.
 
Okay let's take this one step at a time :)

Fine by me my friend ... We'll not skip a one :D

Rounding up suitable parts :scratch:

That's where I am looking for input/advice :shrug:

I'll give you mine and I hope others will chime in as well :nice:

We know that the fuel pump, injectors anf MAF meter need to be changed but it's here where one gets a wide range of opinion :crazy:

Lets talk about those ... Opinions :)

Opinions are great :D
but
1) Some are are nothing more than that :notnice:
and
2) Some have the fruit of successful experience and results behind them :nice:

You can get all bogged down in :crazy:
this guy said this and that guy said that :scratch:

I've found the most reliable info comes from the #2 kind of peeps :Word:
thus
Thats why I pointed you to the power adder boys hang out place

You just have to look at all data and see ........
Which info is just being passed along
and
Which info is based upon actual experience ;)

So, if I'm going to keep boost in the 6-8 psi range on an otherwise stock engine my take on the various posts would indicate that a 190 lph pump, 30/36 lb inj and a matched MAF meter should, with a tune, work well together :cool:

Now ... You have concerns about pump, inj's, and meter
and
You talk about staying at a conservative 6-8 pounds of boost

PUMP

I have concerns about that 190 pump :eek:

You may need to
Go to a larger 255 pump
or
Add an inline pump along with that 190 pump

My bottom line here is ... the 190 alone is not enough :(

:nono: N E V E R :nono: scrimp on fuel

Especially if forced as it helps to keep the charge temp cooler
thus
You need MORE of it than a NA combo :Word:

INJECTORS

30's or 36's are not enough
Here are just two reasons for you to consider with that statement :D

1) Those formulas you find all over the net talk about amount of hp
to determine the inj size.

They deal in flywheel hp and not in rear wheel hp :shock:
and
Consider the hp it takes to drive the blower as well ;)
which means
Drive train loss is not the only loss with blower combos :Word:

2) You're gonna custom tune
thus
You most likely are gonna tune with pressure set at 39 lbs
henceforth
The inj is gonna act smaller than those who tune with elevated pressures

Once Again ... :nono: N E V E R :nono: scrimp on fuel

I'd go with lime green Ford 42's :nice:

METER

I could write a book here ... but I won't :)
Lets just say ... IMHO ... its so critical on our 94-95 Stangs
and
All the more so than on the older Fox Stangs
cause
Our pcm's are load based and it is the meter that sets up the load ;)

The meter and the t curve in the pcm M U S T jive :Word:
and
If the meter is not all that accurate :(
You'll never be able to build a t curve that is worth a dam :bang:

I prefer the meters that use an electronic calibration method
as opposed to
Those that use a mechanical cal

Having said that ... I'd consider a ProM/PMAS or Lightning meter

By working well together I mean that all the componets are not being pushed to their operating limits if that makes sense :shrug:

Or are we dealing with matters where bigger is generally better :shrug:

Your comment about everything working well together is a wise one :nice:

I can't be certain here Richard ... but ... I some how think you may
have seen some older thinking based upon tuning with mechanical
methods like back in the Fox hey day as opposed to working with
the pcm as is more common these days :shrug:

I can assure you ... a 190 pump and 30's or 36's :shock:
will not only be pushed to their limit
IMHO ... they will be pushed beyond it :( :fuss:

Application is also important and you have stated yours plainly :nice:
so
It is not like you are gonna need .........
sumped tank
larger fuel lines
larger fuel rails
etc :crazy:

Soooo ... Nooooo ... Bigger is not ALWAYS better :nono:

If I can help it I would just like to do the job once :bang:

Again ... Wise thinking :nice:

You just gotta look at all the opinions/info to determine which is
valid and which needs to be weeded out :shrug:

We do know that with the current setup the FMU is forcing the FP and injectors to work in a way they were not designed for :eek:

This is so true ... but ... Many have done it for years :D

I will say that over the years I've been on these boards, I've seen on
more than one occasion peeps who have suffered catastrophic events
when something with that tuning method fails :(

Hope I made some sense to ya Richard :shrug:
and
If I wasn't clear on some points ... feel free to ask more :)

Grady
 
Okay Grady, I'll take your advice and over the winter I'll quietly assemble the necessary parts as suggested :nice:

But I must admit that I'm baffled :scratch:

If the 190 lph pump and 36 lb squirters will be maxed out how can the FMU make a 95 lph pump and 19 lb inj deliver the fuel required :shrug:
 
Okay Grady, I'll take your advice and over the winter I'll quietly assemble the necessary parts as suggested :nice:

But I must admit that I'm baffled :scratch:

If the 190 lph pump and 36 lb squirters will be maxed out how can the FMU make a 95 lph pump and 19 lb injectors deliver the fuel required :shrug:

Aren't we doubling the flow for all practical purposes with those higher volume parts :scratch:

Now it occurs to me that you are suggesting that when it comes time to "tune" I won't have to leave potential hp gains on the table and that to maximize the benefits of a forced induction system I'll need the larger capacity :nice:

Is that correct :shrug:
 
Okay Grady, I'll take your advice and over the winter I'll quietly assemble the necessary parts as suggested :nice:

Please ... Be sure to take my thoughts here and stack them up against
those folk that have done forced combos ;)

Make sure they follow the major trends of those who have successfully
done what you seek to do with your Stang :nice:

But I must admit that I'm baffled :scratch:

If the 190 lph pump and 36 lb squirters will be maxed out how can the FMU make a 95 lph pump and 19 lb injectors deliver the fuel required :shrug:

Aren't we doubling the flow for all practical purposes with those higher volume parts :scratch:

Well ... the fmu thing is all about working things at mega high pressures
and it really is no more complicated than that as I see it :shrug:

I see your thinking and I'll give you the way I look at a fuel supply
which
Is all the more compounded when you go forced :crazy:

I see the whole fuel system deal as two trains of thought :shrug:

1) Volume
2) Pressure

Volume

You can have a bunch of pressure but if the volume is wimpy :(
you're gonna run into trouble :bang:

I see the pump and its ability to keep on supplying fuel under A L L
possible conditions as what the volume is all about

Forced or NA ... Stop and think about it :D

Maximum Load being placed upon the fuel system at WOT
A long WOT pull in say third gear

You are really sucking down a bunch of fuel :eek:
and
You are really doing it in a very short time frame :shock:

You gotta be able to feed those injectors :D

Pressure

Again ... tuning with the pcm is N O T about high pressure :nono:

You select inj size based upon ...
The amount needed to feed the combo
and
Working at that lower OEM pressure

You See :)
If the proper size inj is selected :nice:
Its gonna pass adequate fuel without the need for all that pressure ;)

I don't know about you Richard but my Common Sense tells me ...
This method should produce a more stable result

If this kind of thinking is not valid :scratch:

Why don't we see fmu's on Lightnings Ford offers to the general public ;)

Now it occurs to me that you are suggesting that when it comes time to "tune" I won't have to leave potential hp gains on the table and that to maximize the benefits of a forced induction system I'll need the larger capacity :nice:

Is that correct :shrug:

In a nutshell ... You got it :D

I do feel the mechanical fmu tuning method is very sloppy

One could tune the fmu for the best WOT results
and
Possibly not pick up much peak power with a Custom Tune

Two things to keep in mind is ;)

1) there is the possibility
AND
there is the reality
of what happens with forced folk
when most of them go from mechanical to pcm tuning

Most of the time ... B I G gains are to be found with this kind of thing
simply because the tune is S O far off with the fmu and tiny inj's

2) there is W A Y more to tuning than just ... foot flat on the floor :Word:

You just don't have enough flexibility with mechanical tuning to
chase away all those drivability gremlins you are gonna have
when running big injectors :bang:

Tuning with the pcm opens up a whole new world of possibilities :banana:

You get the pcm values all squared away to match the additional
airflow and fuel demands of the blower and you can obtain stock like
or V E R Y close to stock like drivability :nice:

Grady
 
Hello Mods

This is some heavy stuff here :Word:

Seems like it belongs in tuning or tech :D

Not In ... TALK :nono:

btw ... A thread title change would not hurt as well ;)

Grady


Putting this in talk was just an error. Forgot where I was when I created the thread :doh:

Can you move this to Tuning or Tech? :shrug:

As for a title change was "Hello Mods" a hint :rolleyes: