What injectors to go with?

[kruegs74]

Ok this is my setup so far: stock lower end , E303 cam, gt40 heads, FR 1.7 roller rockers, trick flow track heat upper and lower, mac shorty headers. Just got to the injector point now and im not sure if i should go with the 24s or step it up to the 30s. want to go 30s but will it be too much fuel for my setup?

 

[TGgnatsum49]

Unless you have plans in the future for a blower or juice just stick w/ the 24#s. It would be pointless to go w/ the 30's if you dont plan on adding a power adder

 

[Stanger007]

If you are getting a tune or a "calibrated" MAF, nothing wrong at all with going 30s - in fact, that is what I would do -- better to have more fueling capacity that less. The tune will have some benefits over the MAF but that is a totally different issue.

Personal experience... on a Trickflow engine kit with longtubes (a tad more flow than you have) we were seeing 90-100% duty cycle on 24s with the stock fuel pressure and a pegged stock MAF.

Wes

 

[final5-0]

Ok this is my setup so far: stock lower end , E303 cam, gt40 heads, FR 1.7 roller rockers, trick flow track heat upper and lower, mac shorty headers. Just got to the injector point now and im not sure if i should go with the 24s or step it up to the 30s. want to go 30s but will it be too much fuel for my setup?

24's are at the limit or inadequate for some h/c/i combos
with full supporting mods

If you wanna try and get by without a pcm tune
then
24's working with elevated fuel pressures will work
although
that method offers only crude adjustments
and
it is not very precise

Many have done it

30's are more safe for a h/c/i combo in the 300-350rwhp range

The down side to using 30's is .........
Without a pcm tune, they can be a bit much at low pulse width driving
conditions like idle, cruise, etc

With a pcm tune ..............
You most likely will use them at oem fuel pressure
and
You can adjust for smaller output at low pulse width conditions

Sooooooooo

It really depends upon your long term goals for the car

btw ... a 300rwhp NA h/c/i 94-95 Stang that drives like a little stocker
It ain't gonna happen without pcm optimization

Grady

 

[gcomfx.com]

I agree... go big and get a tune for them.

I went with 42lbers and a LMAF. The cost savings on buying a $80 Lightning Mass Air Flow meter goes a long ways towards a chip for the car giving you more than one benefit.

Good info here: http://www.lasotaracing.com/tech.html

 

[5spd GT]

Go 30's if you can get a tune or device to do it, if not stick with 24's. They will flow for that combo

 

[kruegs74]

thanks for all the input. Im thinking the 30s. so you guys think Ill have a crappy idle when I finally get this thing running and before a tune. I really dont know if the one ford performance shop in my area is capable of doing it though. You think I could get it into tune with a tweecer. oh and i have a cobra pcm that i was planning on throwing in.

 

[final5-0]

thanks for all the input. Im thinking the 30s. so you guys think Ill have a crappy idle when I finally get this thing running and before a tune. I really dont know if the one ford performance shop in my area is capable of doing it though. You think I could get it into tune with a tweecer. oh and i have a cobra pcm that i was planning on throwing in.

You can poke around in the tuning forum and see many Tweecer users
give details about what it is like to use one to self tune.

You will find both good and bad

Can you do it

I would not know ... but ... in a nutshell ..........

The interface and software is pretty straight forward
and
You can grasp its operation in a couple of hours

Where you will spend your time is learning the basic operation
of the pcm :Word:

As for drivability ........

When you do up a combo with upgraded inj's and maf .......
You could have two very similar combos and each could
act very differently

Some have been able to avoid a pcm tune by using mechanical
adjustments of tb blade stop screw, tb bleed screw, dizzy twisting,
fuel pressure, etc to find relief.

Others go with a chip or self tuner interface such as PMS, SCT,
Tweecer, etc, to deal with drivability.

I went with a Tweecer and my little 95 GT behaves like a little
stocker in every way except for cam lope.

I might add ... My custom cam has a very narrow lsa which is said
by most to cause the 94-95 pcm to go nuts

You can use the links in my sig to hear my GT idle, see my h/c/i project,
and find a lot of basic stuff about using a Tweecer to self tune a
94-95 Stang based upon my findings.

You can find a lot of good stuff on the wiki as well

Hope this can help get you started

Grady