Fuel 1995 stock Mustang EFI vs aftermarket TBI or Edelbrock injection? Jag Project Car

stasha

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Oct 19, 2019
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I'm posting here because I'm hoping there are some 5.0 EFI experts who might give me some solutions.
I'm desperate and frustrated, and looking for an easy way out!

This is a project car.
I have installed a stock 1995 Mustang 5.0 EFI engine with AT, complete with harness and ECU, into a 1956 Jaguar XK140.
Everything is stock 95 Mustang - engine, AODE, ECU, original wiring harness all pulled from a 1995 Stang.
THIS IS NOT A HOT ROD. I simply wanted to put a more modern engine with EFI into this old car, AND GET IT DONE QUICKLY and on the road!
HOWEVER, installation is far from complete, and the project has bogged down over the past THREE years.

I am at the point where the engine and trans are seated in the car with fuel and return lines all in place, and dual exhaust system all hooked up.
I have been bogged down mainly due to the WIDTH constraints of the XK140 engine compartment. There is no room for me to route the intake ducting except THROUGH the passenger side sidewall and up along the top inside of the wheel well. I can't go straight forward anywhere because all access within the engine compartment is blocked by alternator, radiator, AC compressor, etc.

I DON'T LIKE IT -- not only because I have to fabricate some awkward metal intake ducting in the top inside corner of the right wheelwell, but also I have vague concerns about about figuring out all those wires for the original 95 ECU and harness, along with the unknown worries about programming the Ford ECU (which I hear is difficult).

So, I have been thinking of simply installing an FITech or a Holley Sniper TBI unit, because the descriptions make it seem so simple to install, and they supposedly self-learn and are easy to program.
It seems that all I would have to do is install a basic air filter assembly on top of the TBI, with no worries about placing all the original Ford EFI components (MAF, etc.) or routing ducting and cramming in an air filter somewhere in the wheel well.
AND, I could eliminate all the 1995 wiring and ECU and have this beautiful handheld computer readout, plus tune the darn thing easily (or so the ads say).

BUT, on a simplistic level, these TBIs seem so crude in comparison to the original Ford 5.0 selective injection into each cylinder -- certainly Ford's EFI has technical and efficiency superiority over the TBI, or am I wrong?.

QUESTIONS:
1) Is the $1200 investment in a Sniper or FITech a step backwards, in comparison with just making the original stock Mustang EFI system work?

2) Is the stock Mustang EFI an antiquated old system that needs to be junked? Did Ford spend a decade refining and fine-tuning the original 5.0 EFI to perfection ...or did they just waste that time trying to make a bad system work?

3) Do I need to look into one of those Edelbrock selective injector systems, and spend upwards of $2500 just for simplicity's sake?

4) Are there any suggestions in regards to the direction I should go (short of scrapping this 5.0 engine/trans) -- suggestions as to intake and maybe a simple computer system that would control my EFI as well as AODE autotrans (without requiring going to a tuner)?

Appreciate even opinions!
Desperate and frustrated, and looking for an easy way out!
 
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There are people who would murder you for putting a 5.0 Ford engine in place of the Jag DOHC 6. However, I am not one of them. Some pictures of where you are at now would be helpful.

The Mass Air EFI (89-93) are dependable and offer excellent street performance and reliability when properly maintained. That means no broken parts or shoddy workmanship when you build and assemble the engine and electronics. There is room to grow the stock computer's performance range with aftermarket add-on modules and tuners.

The 89-93 computer and wiring is much simpler and the computer isn't quite as finicky as the 94-95 system is. There is more practical help and information on the 89-93 EFI than the 94-95. There are also aftermarket wiring harness kits made for swapping an 89-93 computer into various vehicles; they make a difficult job much simpler.

The upper intake manifold has 3 different versions:
The 95 has an extension with a 45° bend in it. The throttle body points towards the passenger side headlight.
The 87-93 HO version is short and straight into the upper intake manifold. The intake for the throttle body is 90° with the passenger side rocker arm cover and points towards the passenger side wheel.
The passenger car and some truck versions just flip the intake around so that the throttle body intake points towards the driver's side wheel. The intake manifold may have a different upper manifold bolt pattern. Therefore, you may not be able to take the 87-93 HO upper intake and turn it to point towards the driver's side wheel.


The following are diagrams courtesy of Tmoss & Stang&2birds

See the following website for some help from Tmoss (diagram designer) & Stang&2Birds (website host) for help on 88-95 wiring; http://www.veryuseful.com/mustang/tech/engine/ Everyone should bookmark this site.


TFI module wiring for 94-95 Mustang GT
http://www.veryuseful.com/mustang/tech/engine/images/Mustang-94-95-IgnitionControlModule.gif

Complete computer, actuator & sensor wiring diagram for 94-95 Mustangs

Complete computer, actuator & sensor wiring diagram for 91-93 Mass Air Mustangs

Complete computer, actuator & sensor wiring diagram for 88-90 Mass Air Mustangs

5.0 wiring diagram for Fuel Injectors, Sensors, and Actuators

Main body EFI wiring harness

Ignition switch wiring

O2 sensor wiring harness

Vacuum diagram 89-93 Mustangs

HVAC vacuum diagram

TFI module differences & pin out

Fuse box layout

Mustang 5.0 Lights and Radio schematic, by TMoss:
http://www.veryuseful.com/mustang/tech/engine/images/mustangFoxLights-Radio_diag.gif

87-92 power window wiring

93 power window wiring

T5 Cutaway showing T5 internal parts

Visual comparison of the Ford Fuel Injectors, picture by TMoss:

Convertible top motor wiring http://www.veryuseful.com/mustang/tech/engine/images/mustang88VertTopMotorCkt.gif

Engine mounted fuel injector harness

Location of the TPS, IAB, and the 10-pin connectors on a 5.0, picture by TMoss:

Starter circuit

Alternator diagram for 94-95 Mustangs.
 

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I too would love to see pictures of this car. My "opinion" would be an after market system like the megasquirt or something like you are already looking at. A91what is already on this thread. He helps lots of people with the megasquirt stuff. I personally have no experience with the aftermarket systems. This is all based on watching and reading what others on here are doing with their cars. Mr jrichker is a treasure trove of knowledge as well.
 
This is what I would do.
fitech or holley stand alone efi, they are made for converting efi on vintage cars, it also allows you to put an air cleaner on top of the engine, you may have clearance issues with the hood but this gives you fresh wiring and the ability to hide most all the electronic stuff. You will need to address the ignition system but there are options for this too.
you have a very small amount of space under that hood, you could use the fox intake and run it into the fender well but I think you are trying to avoid that.
 
I have lots of answers and retorts and responses .. believe me, I have been thru the mill with learning about the 5.0EFI. I have personally rebuilt the engine and probably know it better, on that end, than most on this forum.
HOWEVER, beyond the rebuild (and searching for intake ports -- yes, jrichker, I have EVERY ONE of those variously angled intake versions!! I am a junkyard heavy... none of them will give me a route for intake ducting better than thru the sidewall), I profess ignorance: ECU, what wires do I use on the stock wiring harness, how to tune the engine to this chassis, etc.
So, it is unlikely that there is a better way to route the present stock intake ducting than thru the sidewall.
(I have attached a pic of when I tried a 90deg Mountaineer intake -- no room to run a duct over the center and top of the engine; BTW, the 1995 45deg intake ran right into the alternator.)

BUT, is there a no-brainer system that is equal to, or better than, or EASIER TO INSTALL, than continuing with my stock 5.0 EFI installation using the 1995 ECU?

jrichker Thanks for those excellent resources, - incredible library there ----- but but but... I have a 1995 5.0 with the full wiring harness and ECU. Are you saying I should retrograde to a pre-93 ECU (you know the ECU runs about $500, for something over 27 years old!!)?

Should I read all the various sources and proceed with what I have, or should I just shuck something that MIGHT BE SUBSTANDARD and problematic, and which is over 2 decades, and go with ANYTHING that is more advanced???
I do not know what this might be and that's why I'm asking for input.

No, I do not want to keep a "Model T engine" original -- I just want it to work better and without a hassle. DAILY DRIVER! Ever seen an XK140 that was a daily driver? Unlikely!!
That's one of the reasons that I put the Ford 5.0 into this classic car (it originally had a 302ci before I acquired the car, so was set up for a SBF). I wanted reliability for a daily driver with AC, a modicum of HP, a powerful alternator (BTW for you classic diehards, "reliable" is NOT an original Jag 2.4/2.8/4.2 DOHC engine -- I HAVE one of those, so I speak from experience).

So, suggestions how to easiest solve my intake and ECU concerns?

Attached are some pics.
 

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I too would love to see pictures of this car. My "opinion" would be an after market system like the megasquirt or something like you are already looking at. A91what is already on this thread. He helps lots of people with the megasquirt stuff. I personally have no experience with the aftermarket systems. This is all based on watching and reading what others on here are doing with their cars. Mr jrichker is a treasure trove of knowledge as well.

Olive - I'm like you... I have read a lot about the MS (for my 87 Porsche turbo conversion), and there is no doubt that it requires a tuner -- a "normal" guy cannot set it up in his garage. Too complicated. Something simpler.
 
Anything you use will need to have a transmission controller. You can opt to use a bauman unit to this end.

I would suggest a pimpxshift to do both the engine and the transmission. This will plug into the factory harness, j suggest you speak with @Stinger for specifics if you decide to go that route.
With a standalone like a megasquirt or pimpxshift you wont need the maf and can simply use a filter on the throttle body to get around the issue you are having with routing. It's not a perfect solution but will get the job done.

If you think the fitech or holley will not need any human intervention you are mistaken.
 
pictures of what you have to work with please.
Steve - I have followed you on some other threads in regards to tuning, and I am slightly interested -- but also worried that this is something NEVER within my control. I just have to remember: SIMPLE, DAILY DRIVER, ABLE TO SET IT UP AND FIX IT MYSELF, and no College Degree in MegaqSquirt required.
 
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Anything you use will need to have a transmission controller. You can opt to use a bauman unit to this end.

I would suggest a pimpxshift to do both the engine and the transmission. This will plug into the factory harness, j suggest you speak with @Stinger for specifics if you decide to go that route.
With a standalone like a megasquirt or pimpxshift you wont need the maf and can simply use a filter on the throttle body to get around the issue you are having with routing. It's not a perfect solution but will get the job done.

If you think the fitech or holley will not need any human intervention you are mistaken.
Thanks for the info on pimpxshift . I guess having a single ECU that controls engine and AT is why I am still hanging on to the idea that the original ECU might work. However, getting rid of the MAF might be exactly the answer to the problem about my intake ducting: an EFI that would not require an MAF mounted out there should give me something like the PRoFlow or SNiper or FITech solution -- a simple air filter on top of the unit.
But how simple is pimpxshift to understand and install? Just a quick read regarding pimpxshift mentions the words "MegaSquirt", which causes me to worry about complexity.
Is it a simple plug and play??
Do I just buy the unit, plug it in, and drive off? OR do I need to call in an expert to set it up for me -- and every time there is a problem, I need to give it to someone to fix? Not good for a daily driver!
Yah, I''m looking for Dodge Minivan reliability with XK140 looks, and something with 200HP+ in a light chassis.

Thanks.
 
This is what I would do.
fitech or holley stand alone efi, they are made for converting efi on vintage cars, it also allows you to put an air cleaner on top of the engine, you may have clearance issues with the hood but this gives you fresh wiring and the ability to hide most all the electronic stuff. You will need to address the ignition system but there are options for this too.
you have a very small amount of space under that hood, you could use the fox intake and run it into the fender well but I think you are trying to avoid that.
Whew. Full circle, but yes, that intake is my major stumbling block. However, would this be a step backwards in regards to a TBI versus delivery of fuel tuned to EACH cylinder?
Maybe I am getting too stuck on this technical detail, when all I want is a daily driver with a modicum of more modern engine technology (i.e, no carbs).
 
You will have to make some decisions, wiring in the eec from the mustang, consider the harness is 25 years old and stuff there not needed.
The stand alone stuff like microsquirt uses the injectors, intake and some other stuff and is totally programmable, @a91what can explain that system better than I.
The fitech/holley system, like I stated before was designed to work on modern engines in vintage bodies.
it is not a step back in technology, it's just a different system.
You already have the intake system and if you can plum the incoming air to your satisfaction the least expensive would be the ms system.