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Topic: 3.8 CFI to 5.0 CFI "HO" (Read 1770 times) previous topic - next topic

3.8 CFI to 5.0 CFI "HO"

I just recently picked up an 87 Tbird with a 3.8 and while I was at the junkyard looking for a front end I came across 84/85 fox body ltd with the 5.0 CFI HO in it and grabbed the motor for $100. I didnt see a computer in it or even much of an interior for that matter. Anyway I was wondering if the 3.8 computer would run it, or if I could just use a 5.0 CFI computer out of a another Bird.
85 Tbird 5.0
78 F150 351w
13 F150 4x4 3.5 Ecoboost

3.8 CFI to 5.0 CFI "HO"

Reply #1 –
ok,, first off,
what makes you think its an HO cfi?  those things are about as rare as leftovers in my fridge:hick:

as for the swap, you are gong to be very amazed at how easy it is.  Your existing computer is layed out for two fuel injectors and like wise with the 88 tbird belive it or not.

Your existing harness isnt gonna need hardly any mods, your use of a V8 CFI computer is likely optional but prefered.  I would go back and find the eec (right hand kick panel front passanger side interior).  This would be just for the sake that the computer would pulse the injectors at a different rate for the CFI 8cyl vs the CFI 6cyl.  The 8cyl has different color injectors.

Yours are likely blue top or mistaken as black. Clean them off and on the side there will be a number, post that up.  Also let us know if the injectors are navy blue or not.

my diy link has a lot of cfi info in it (above my sig).  Also, there are a ton of electrical diagrams in electrical tech.

3.8 CFI to 5.0 CFI "HO"

Reply #2 –
If the LTD was an LTD LX, then it was an HO CFI, if not, then no.
Long live the 4-eyes!  - '83 Tbird Turbo

3.8 CFI to 5.0 CFI "HO"

Reply #3 –
The numbers are E4ZE-CA and theres also a 443, 060, and 0280150403. Not sure which ones you needed lol. They are a tan color.

The car had a hole for a spotlight and was white. I figured it might have been unmarked cop car at one time. Probably why I thought it was an HO.
85 Tbird 5.0
78 F150 351w
13 F150 4x4 3.5 Ecoboost

3.8 CFI to 5.0 CFI "HO"

Reply #4 –
those are HO numbers. Injector tops should be gray but tan might be non bosch.  there should be little numbers on the side of the injector with E4ZE- (what comes next??)

How much do you want for that eec and cfi?

3.8 CFI to 5.0 CFI "HO"

Reply #5 –
All that is after the E4ZE is CA. Thats on the injector tops, I didnt see anything on the injector body itself. At the base of the whole CFI unit is E4ZE BA A 4E 08.

No I dont plan on selling the CFI. However if your talking about 3.8 CFI and EEC I'll be selling it as soon as I find an EEC for this 5.0.
85 Tbird 5.0
78 F150 351w
13 F150 4x4 3.5 Ecoboost

3.8 CFI to 5.0 CFI "HO"

Reply #6 –
Quote from: 88FoxBird;180630
I didnt see a computer in it

Quote from: jcassity;180892

How much do you want for that eec

:shakehead
One 88

3.8 CFI to 5.0 CFI "HO"

Reply #7 –
Quote from: CougarSE;181054
:shakehead


back off buzz bait:flame:

some folks dont know where the computers are at.:shakeass:

3.8 CFI to 5.0 CFI "HO"

Reply #8 –
This one doesnt have one in it. Someone else took it. The LTD is at a junkyard. Unless your talking about the 3.8 eec, that I have.

Is there any difference between the HO and SO eec?
85 Tbird 5.0
78 F150 351w
13 F150 4x4 3.5 Ecoboost

3.8 CFI to 5.0 CFI "HO"

Reply #9 –
other than what i mentioned,, its going to be just plug and play.

I had an 84 3.8 and an 84 5.0.  THats been a lonnnnggg time ago and i can not remember how the 5.0cfi charge system was layed out.

If the alt is on the pass side cfi 5.0, your in better shape.  either way its gonna be an easy swap. 

even the 3.8 eec will make it run, but i would try like heck to get at the least a cfi 5.0 for injector pulse purposes.  I am saying this but not knowing exactly what differnces there are with the two different frimware loaded on the eec's.

i do know for a fact though,, a cfi 5.0 eec will run a cfi 3.8 engine, visa versa.

The HO CFI that you have should look different than the 3.8 with respect to the pass rear having a choke pull off assembly.  just hacksaw that ear off the cfi and toss that part,, dont need that.  You will fab back into the layout the idle speed control motor assembly to the front drivers side of the cfi.

Also,, i dont not believe that HO CFI has a gold pcv tube on the rear driver side like the 3.8 does.  no matter though, that will be fine not being used either.

block off the egr assembly like i did or just install the egr.

You do need the spacer though, and if your interested in blocking off the egr system all together, i have a pattern for a gasket that would install below the spacer blocking off the egr system all together.

3.8 CFI to 5.0 CFI "HO"

Reply #10 –
got pics of that cfi

3.8 CFI to 5.0 CFI "HO"

Reply #11 –
I'll get those tomarrow when I get my camera back.

EDIT- One more question, how well will the v6 trans hold up?
85 Tbird 5.0
78 F150 351w
13 F150 4x4 3.5 Ecoboost

3.8 CFI to 5.0 CFI "HO"

Reply #12 –
if you want, you can send me the cfi, and ill do the mods you need done as well as the injector screen / fpr/egr/fuel flow/ISC mods all in one shot.

3.8 CFI to 5.0 CFI "HO"

Reply #13 –
I've got a EEC from a standard 5.0 cfi.  It works good.  Probably a closer mate then the 3.8 one you have.  Let me know and I'll hook you up.
84 TC 302 -5.0L/t5/7.5 locking rear and a 3.45 gear, Edelbrock Intake, Aluminum Heads, Edlebrock 65mm Throttlebody, Edlebrock Cam, 24lb injectors & MAS Air Sensor calibrated via chip,  BBK headers, Catback H pipe, Magnaflow lers :evilgrin:
:pics-stfu:

 Project Thread with pics

3.8 CFI to 5.0 CFI "HO"

Reply #14 –
The E4ZE-CA are the 52lb injectors, which are unique to the CFI HO...

For it to run like it should you need the original type EEC...

The std CFI 5.0 uses 46lb inj and the 3.8 is 37lb...

A EEC from a 5.0 '84-'85 Automatic Stang or a LSC Lincoln(not std MK VII) should be OK...