View Full Version : Injector questions...........

08-12-2007, 09:07 PM
During my cleanup,wondering what lb. injectors that I have.They have a yellow or gold body.What injectors should I use if I plan to go 5 or 10% in the future and can I run them now on my current stock rebuild?The only thing Ive done is open up the exhaust flanges and gasket match the intake and heads.Std bore and crank, Stock Cam,nothing fancy............

08-12-2007, 10:25 PM

08-12-2007, 10:35 PM
I don't know what the stock lbs. are, but my caps are red. When I did the top end on my 89 automatic, I did the gasket match, ported 94 exhaust collector, cat-delete, and 5% pulley.

After I finished it up, I ran it waaaaaay up the speedo on IH-10 north of Borene, and it didn't quit pulling. So, I suspect that you'll be okay with the stock injectors on your set-up.


08-12-2007, 11:39 PM
heres a thread letting u know what hp injectors can handle :


good luck !

08-12-2007, 11:56 PM
The original 91 injectors are yellow/gold bodied and the ones from my spare 93 motor are red.What is the difference.What application do the higher pressure injectors come from?Lightning, 5.0 H.O.,Nissan or what?????

08-13-2007, 12:30 AM
my original 91 injectors were red, IIRC the yellow tops are 19 lbs :eek:

08-13-2007, 03:28 PM
The color of the body of the injector (the metal part), the o-rings, and the pintle cap should not matter. The only part that is color-coded is the plastic part on top (with the electrical and fuel connections). The 89-93 cars came with 30lb injectors, which have a red top. The later cars came with 36lb injectors, and I think that they had a dark blue top. Yellow top Ford (Bosch-style) injectors are 19lb, so I think you must either have aftermarket injectors (possibly Accel brand), or they are the WRONG injectors! Which would be bad.

08-13-2007, 06:27 PM
I'm not sure but didn't the na 3.8 in the LX's have 19 lb injectors?

08-13-2007, 07:33 PM
OK,my bad,It was dark last night when I saw this, now during daylight,these have a gold or tan center section with gray or off white tops.They have FOSA-A1A on them.I highly doubt that this car ran for 107,000 plus miles without burning a piston,especially the way I drove it(when I could get my hands on it),and for as well as it ran,before HG's went,when my father-in-law owned it.Please help.............

08-13-2007, 07:44 PM
The more I think about it, the more I recall the '94 LX 3.8 having those tan injectors in it.

08-13-2007, 07:57 PM

Check out the injectors in the top right of this page. I think those might match your injectors. The page quoted says that they are 15lb. I remember the N/A 3.8 engines having 14lb injectors, although I could be wrong. The later 3.8s (once the splitport engines came into service) have larger injectors (19 to 21 lbs).

Could your part number be F0SE-A1A ? On the Internet, I could find reference to that part number for N/A 3.8's, but I could not find any F0SA-A1A.

08-13-2007, 08:22 PM
OOPS,my bad again,They are FOSE-A1A..........Long day at work I guess

08-13-2007, 08:24 PM
They also have another number on the other side..0 280 150 907.....if this helps

08-13-2007, 09:28 PM

08-14-2007, 07:30 AM
Back to the top.............

08-14-2007, 10:48 AM
If you have that number, I am pretty sure that you have the wrong injectors. The stock SC injectors are red tops or dark blue tops.

What do you know about the history of the engine? I see that you described it as a "rebuild". When was it done?

To answer your other question, I think that stock SC injectors would be fine for your planned mod level. If you want some "headroom," you could go bigger, but it's up to you. If you need a set of 30lbs, let me know. It's a good idea to have used injectors cleaned before use as well.


I found a site that lists the alternate part number that you quoted:


Read down to the section "Alternate Numbers ..." and you will see exactly both of the part numbers you quoted. Scroll down further and you will see the lb/hr rating.

08-14-2007, 08:15 PM
Thanks,S Mazza,you have been very helpful.Your right ,these are 14 lb injectors.I just cant believe that this car ran as well as it did and also for as long as it did with these in it.Father-law bought it in 99, drove it till 01 when it blew HG's.It showed 107K on the clock then and when I aquired it a year ago,it showed the same mileage.This car made at least 2 trips to California that I know of as well as commuting back and forth to work.Whenever I drove it,I was never gentle with it.I thought it ran strong then.I'm doing the rebuild now after it has sat motion-less for 6 years.I just want a reliable,stout engine and with everyones' help here,I'm confident that I will.Man,this thing should run awe--some with the correct injectors in it !!!!!!!!!!

08-20-2007, 05:57 PM
OK,new question.......2 different injectors,red tops,1 with F1SE-D1A(0 280 150 911),the other has F1SE-E5A(0 280 150 945).Which injector is correct for my 91 SC? The spare engine that I have has both numbers installed in it.I have been told that the D1A injectors are low resistance.....Confused,Concerned,.....Which way do I go here???

XR7 Dave
08-20-2007, 07:27 PM
Injector size and EEC calibration are closely tied to each other. I can't tell you what you do or do not have but I can tell you that a normal SC will not run with 14lb injectors. At all. Something is up. Do you have a picture of these injectors you have been running? And do you have an SC or an LX? What is your EEC code? Do you have a chip?

08-20-2007, 08:23 PM
The 14lb injector problem has been solved.Everything is stock.I just have mis-matched injectors on another engine that I have as a spare and want to know which red top injector number is correct.Everything is SC not LX except for the 14lb injectors that were installed on the original motor.I just need to know which red top 30lb injector to go with so that I can buy a new set.The people at Five O Motorsports say that the (911) injectors are low resistance and the (945) ones are high resistance.Thanks for any help,Bryce

08-21-2007, 02:41 PM
Hi Bryce. Sorry, I missed your post from last week. I am glad that I have been helpful. As for the resistance, you need the high impedance injectors. I haven't heard of red top injectors that are low impedance. That doesn't mean they don't exist, it's just that I have never heard of them. An interesting note is that the 4-digit prefix to the part numbers is the same. F1SE equals 1991 Thunderbird, Engine category. (F = 90's, 1 = 1, S = Thunderbird / Cougar, E = Engine.) And I am pretty sure that none of the Thunderbirds made in 1991 used low-impedance injectors.

Now, like Dave Dalke was saying, it's really weird that this car had 14lb injectors in it. It would seem like someone must have either calibrated for them somehow or had modified the injectors to flow more. I just don't know how it could have run all right with them in there! How much boost does the supercharger produce?

Edit: To verify whether the red-tops really vary in impedance, you can test for resistance across the terminals of each one. High impedance injectors should measure 11 to 16 ohms. Low will measure about 1 to 5 ohms. That should clear up that problem once and for all. I would bet that both types of red top are high impedance.

08-21-2007, 11:39 PM
Thanks to XR7 Dave and to S MAZZA(again) today for steering me in the right direction.Your advise and knowledge is why this webite will exist for a very long time.

08-22-2007, 01:50 AM
The injectors must have been modofied for higher flow. The injectors in my brother's car were altered for higher flow rate, so the body/top is not the green top you would expect for a 42 lb injector.