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  • 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk-

Fox 4 Cyl to V8 Swap Info Thread

  • Thread starter Thread starter Matt01
  • Start date Start date Jul 12, 2021

Matt01

Active Member
Jul 23, 2016
34
15
28
Jul 12, 2021
#1
  • Jul 12, 2021
  • #1
Hey Guys, don't post much, but I did read plenty of this forum over the last few weeks while doing my swap, and I want to share my experience for someone in the future doing the swap. Hopefully you could be a little more prepared.
I had a weeks vacation to do it, luckily Fedex was MVP and delivered all my last minute shipments on time to Montreal, Canada (thank you!!!!!)

My car is an 1989 4cyl manual, I had a motor from a 95 GT from a parts car thats been scrapped and gone for years, so I had nothing but the engine really. This is what you'll need to get the swap done nicely.
Motor, mine was almost free, I picked up a used t5 and bellhousing.
Flywheel, clutch kit, clutch fork (rockauto) and CLUTCH CABLE, the 4 cyl cable isnt exactly the same. Got my cable from Summit
The tranny crossmember and driveshaft are the same, you do not need this.
Engine/Transmission starter shim plate if the donor car was an automatic like mine was. (summit)

I swapped to an explorer upper/lower intake right away to get rid of that ugly 95 stuff. So you'll need a fox throttle body with TPS, MAF housing (the sensor itself is the same on the 95) if you do the explorer intake swap, you'll need an intake manifold gasket set. I also changed header gaskets while the engine was out. The IAT I installed in the intake pipe


Full intake kit, the 95 stuff wont work, and the 4cyl stuff wont work, i got the 80$ one on LMR, it's really nice.
I purchased a Painless Harness, which honestly did install pretty easily on my 95 motor with a foxbody distributor. the 95 distributor cannot be used. I bought one from Rockauto, got a Cardone, which killed TFI modules every 3 minutes, this really slowed down my progress as i was trying to figure out if it was a wiring issue or what it was.
Throttle Cable bracket and fox body throttle cable. I dont know if the 95 cable would work, but I didnt have it. I ordered the bracket on LMR
The 4cyl has fuel lines that are on the wrong side, I purchased AN Ford fuel line adapters and 90 degree fittings and ran rubber hose to the fuel rail. Works flawlessly. Didnt touch the pump or lines at all.
ECM, Computer, i was lucky enough to find an A9P in the junkyard ages ago and grabbed it.
O2 sensors x2. I couldnt reuse them off the parts car, they were seized on, and 1 got broken during removal (Rockauto)
Flywheel bolts, do you have them? I got ARPs from Summit.
Crankshaft Rear main seal and transmission output shaft seal, you're there, nows a good time.
Fox upper and lower rad hose, again the 95 stuff is weirdly sized the fox stuff fits perfectly.
Electric fan + fan controller. Electric fans are just better, 95 + 4cyl had electric fans. I grabbed my from an SN95 in the junkyard, it should do fine for now, and I ordered a Mishimoto fan controller to run them
Radiator overflow, I found a universal on amazon, it looks very similar to the one LMR sells, made some bracketry to mount it, should be fine.
Clutch Fork cover (LMR, really didnt fit well though, havent installed it yet)
Thermostat housing, the OEM one does not have a spot on top for a sensor, and the jobber ones do, you might need this extra spot for a gauge, fan switch, or temp sensor.
v8 Tach (if you want the oem look) i got one, but it doesnt fit in my 89 cluster, they must have been a change somewhere
Note: Keep the 95 wiring for the starter and alternator, you'll be reusing it on the fox.

Exhaust, this was a huge pain in the ass. This was probably worse than the whole rest of the swap.
First you'll need
Mid pipe hanger (a/t or manual are different) (LMR)
muffler hanger kit, and end hanger kit for the tail pipes
x pipe or h pipe or some kind of downpipe,
pipes and mufflers and hangers.
Now you'll have to reroute the rear brake line (LMR has a kit) if you want to run full tailpipes (ill do it eventually) if not you'll have to modify the rear passenger side brake line bracket to accept the hanger for the muffler. Driver side is no mod, fits perfectly
I had kept the mufflers off the 95 GT, they were some kind of Jobber, but it is so loud (ridiculously loud) I ordered new stuff off rockauto. No tailpipes for now, no rerouting the brake lines.

Anyone interested in some pics, first last pic of car before swap

pulled the heart

new heart after some paint and a new oil pan

pressure washed clean

overflow bottle with bracket, with fan wires waiting to go somewhere

painless harness fully shoved into the space behind the carpet

old intake off, cleaned up

pretty much done


Thanks for looking!
-Matt
 
Reactions: Robinson, Wayne Waldrep, WindsorPenchant and 1 other person

JD1964

there is enough sticking out to grab on to
15 Year Member
Jun 28, 2013
3,432
1,524
194
Maryland
Jul 14, 2021
#2
  • Jul 14, 2021
  • #2
Thanks for all the info. The car looks nice
 

Wayne Waldrep

Before I post a pic, do you have one of yours?
20+ Year Stangneter
Apr 14, 2003
1,338
659
143
Cuba, AL
Jul 16, 2021
#3
  • Jul 16, 2021
  • #3
Good post man. Glad you logged all that info in.
 
1

1977 Mustang II

Member
Aug 17, 2021
9
5
13
Piperton
Aug 23, 2021
#4
  • Aug 23, 2021
  • #4
Matt01 said:
Hey Guys, don't post much, but I did read plenty of this forum over the last few weeks while doing my swap, and I want to share my experience for someone in the future doing the swap. Hopefully you could be a little more prepared.
I had a weeks vacation to do it, luckily Fedex was MVP and delivered all my last minute shipments on time to Montreal, Canada (thank you!!!!!)

My car is an 1989 4cyl manual, I had a motor from a 95 GT from a parts car thats been scrapped and gone for years, so I had nothing but the engine really. This is what you'll need to get the swap done nicely.
Motor, mine was almost free, I picked up a used t5 and bellhousing.
Flywheel, clutch kit, clutch fork (rockauto) and CLUTCH CABLE, the 4 cyl cable isnt exactly the same. Got my cable from Summit
The tranny crossmember and driveshaft are the same, you do not need this.
Engine/Transmission starter shim plate if the donor car was an automatic like mine was. (summit)

I swapped to an explorer upper/lower intake right away to get rid of that ugly 95 stuff. So you'll need a fox throttle body with TPS, MAF housing (the sensor itself is the same on the 95) if you do the explorer intake swap, you'll need an intake manifold gasket set. I also changed header gaskets while the engine was out. The IAT I installed in the intake pipe


Full intake kit, the 95 stuff wont work, and the 4cyl stuff wont work, i got the 80$ one on LMR, it's really nice.
I purchased a Painless Harness, which honestly did install pretty easily on my 95 motor with a foxbody distributor. the 95 distributor cannot be used. I bought one from Rockauto, got a Cardone, which killed TFI modules every 3 minutes, this really slowed down my progress as i was trying to figure out if it was a wiring issue or what it was.
Throttle Cable bracket and fox body throttle cable. I dont know if the 95 cable would work, but I didnt have it. I ordered the bracket on LMR
The 4cyl has fuel lines that are on the wrong side, I purchased AN Ford fuel line adapters and 90 degree fittings and ran rubber hose to the fuel rail. Works flawlessly. Didnt touch the pump or lines at all.
ECM, Computer, i was lucky enough to find an A9P in the junkyard ages ago and grabbed it.
O2 sensors x2. I couldnt reuse them off the parts car, they were seized on, and 1 got broken during removal (Rockauto)
Flywheel bolts, do you have them? I got ARPs from Summit.
Crankshaft Rear main seal and transmission output shaft seal, you're there, nows a good time.
Fox upper and lower rad hose, again the 95 stuff is weirdly sized the fox stuff fits perfectly.
Electric fan + fan controller. Electric fans are just better, 95 + 4cyl had electric fans. I grabbed my from an SN95 in the junkyard, it should do fine for now, and I ordered a Mishimoto fan controller to run them
Radiator overflow, I found a universal on amazon, it looks very similar to the one LMR sells, made some bracketry to mount it, should be fine.
Clutch Fork cover (LMR, really didnt fit well though, havent installed it yet)
Thermostat housing, the OEM one does not have a spot on top for a sensor, and the jobber ones do, you might need this extra spot for a gauge, fan switch, or temp sensor.
v8 Tach (if you want the oem look) i got one, but it doesnt fit in my 89 cluster, they must have been a change somewhere
Note: Keep the 95 wiring for the starter and alternator, you'll be reusing it on the fox.

Exhaust, this was a huge pain in the ass. This was probably worse than the whole rest of the swap.
First you'll need
Mid pipe hanger (a/t or manual are different) (LMR)
muffler hanger kit, and end hanger kit for the tail pipes
x pipe or h pipe or some kind of downpipe,
pipes and mufflers and hangers.
Now you'll have to reroute the rear brake line (LMR has a kit) if you want to run full tailpipes (ill do it eventually) if not you'll have to modify the rear passenger side brake line bracket to accept the hanger for the muffler. Driver side is no mod, fits perfectly
I had kept the mufflers off the 95 GT, they were some kind of Jobber, but it is so loud (ridiculously loud) I ordered new stuff off rockauto. No tailpipes for now, no rerouting the brake lines.

Anyone interested in some pics, first last pic of car before swap

pulled the heart

new heart after some paint and a new oil pan

pressure washed clean

overflow bottle with bracket, with fan wires waiting to go somewhere

painless harness fully shoved into the space behind the carpet

old intake off, cleaned up

pretty much done


Thanks for looking!
-Matt
Click to expand...
Is the 4 cylinder for sale? I could be interested if you can share some details with me. Also what about the trans? Four speed or auto?
 

91TwighlightGT

20+ Year Stangneter
Sep 8, 2002
1,190
375
124
Missouri
Aug 24, 2021
#5
  • Aug 24, 2021
  • #5
He said his is a manual, which would make it a T5 Five Speed. It won't be super useful outside of a naturally aspirated four cylinder application because it is pretty weak even compared to a glass jawed V8 spec T5.
 

Matt01

Active Member
Jul 23, 2016
34
15
28
Aug 24, 2021
#6
  • Aug 24, 2021
  • #6
1977 Mustang II said:
Is the 4 cylinder for sale? I could be interested if you can share some details with me. Also what about the trans? Four speed or auto?
Click to expand...
sure I could sell the engine it has 120k on it, pretty mint. Located in Montreal, where are you?

ya the tranny is manual, but Im gonna hold onto that for my Merkur.
 

90sickfox

Wasn't a pretty sight...and I've got big hands
SN Certified Technician
Mar 2, 2015
6,945
5,816
213
Aug 25, 2021
#7
  • Aug 25, 2021
  • #7
The 4 banger transmission is actually under rated. Mine lived for a very long time behind 302, 306, 347, and a short time behind my turbo 331. It shifted and still worked flawlessly so it's staying with me for a while longer.
 
Reactions: Gs1987GT and General karthief

02 281 GT

Agreed...My wife has great Boobs
15 Year Member
Feb 3, 2009
3,208
1,972
194
Cabot, AR
Aug 26, 2021
#8
  • Aug 26, 2021
  • #8
I ran a 4-cylinder transmission in my '86 GT out of necessity (guy said it was out of an '88 GT, I was a poor kid who couldn't afford another transmission once I discovered otherwise). It had a lot of issues to begin with that I attribute to it not being in as good shape as I was led to believe. The only downside to the 4-cylinder transmission is its gearing. First gear is plenty steep at 3.97:1. It makes it all but useless unless you have an engine that likes to rev.
 
S

Slumone

New Member
May 7, 2019
24
0
1
14609
Sep 4, 2021
#9
  • Sep 4, 2021
  • #9
1977 Mustang II said:
Is the 4 cylinder for sale? I could be interested if you can share some details with me. Also what about the trans? Four speed or auto?
Click to expand...
Is there still a market for the 2.3? I have two of them.
 
S

Slumone

New Member
May 7, 2019
24
0
1
14609
Sep 4, 2021
#10
  • Sep 4, 2021
  • #10
91TwighlightGT said:
He said his is a manual, which would make it a T5 Five Speed. It won't be super useful outside of a naturally aspirated four cylinder application because it is pretty weak even compared to a glass jawed V8 spec T5.
Click to expand...
The t5 world class can easily withstand a 2.3 turbo from 1986 which had 205hp and 200lb/ft in manual transmission versions, 20 less than the EFI 5.0 of 1987. The torque of the turbo came much later in the RPM range than a 5.0 so considerably less shocking to the drivetrain. The turbo T5 had a few differences from the NA the main of which I believe was the input shaft bearing, which is easily swapped if one is so inclined. The main difference between the 2.3 and 5.0 WC T5's other than gearing are the input shafts and bearing which are different to accommodate the larger flywheel and clutch assembly. So neither can fit behind the other motor without swapping the input shaft and bell housing. Either transmission can do just fine behind any factory spec Ford motor of that era. If you build up your motor, you should consider swapping or building up your T5. You can make a T5 withstand some pretty torquey motors if you really want to. It will cost you of course, but then so will that other transmission which is likely heavier.

The A4LD Automatics that were behind the 2.3 were considerably more weak than the T5. Any 87-88 turbocoupe with an automatic came factory with 40 less HP than the manual and no boost in 1st or 2nd gear. The AOD in comparison was a beast but far too heavy for the NA 4 cylinder cars.
 
R

Robinson

Member
Apr 6, 2023
18
2
13
TENNESSEE
Apr 8, 2023
#11
  • Apr 8, 2023
  • #11
m
Matt i like your build it has inspired me greatly on this rainy day, and you have definitely made me feel much better...?
on my 93notch i only have 1 hump in my xcrossmember so will i need to purchase 1 from lmr?..being i will be running dual exhaust...and glad to hear about these gas lines because at first i was trying to follow INFAMOUS PROJECTS out of CANADA and doing his way on this swap,meaning gas tank lines etc. but i quickly reminded myself that i don't have his$ nor his connections........Also if i get the pimpxs , will the painless wiring harness plug right in?
 
R

Robinson

Member
Apr 6, 2023
18
2
13
TENNESSEE
Apr 8, 2023
#12
  • Apr 8, 2023
  • #12
Matt your can use a A9p ecu ? With a manual? Because I do believe that is what is in this 1993 convertible auto I have and it runs but I read somewhere if I use this ecu instead of A9L , I could have idle problems etc. …. Correct me if im wrong here
 

AeroCoupe

lube between the nut and the face. I know my lubes
Founding Member
Oct 28, 2001
5,877
4,002
183
Claremore, OK
Apr 8, 2023
#13
  • Apr 8, 2023
  • #13
I would suggest you go and read this thread over on the Corral as it covers most everything on the swap.

https://www.corral.net/threads/official-four-cylinder-to-v8-conversion-dos-donts-merged-threads.795562/
 
R

Robinson

Member
Apr 6, 2023
18
2
13
TENNESSEE
Apr 9, 2023
#14
  • Apr 9, 2023
  • #14
 

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R

Robinson

Member
Apr 6, 2023
18
2
13
TENNESSEE
Apr 9, 2023
#15
  • Apr 9, 2023
  • #15
I posted all this wiring on donor car to see if I can get some help on. What I should by and not? …
 

90sickfox

Wasn't a pretty sight...and I've got big hands
SN Certified Technician
Mar 2, 2015
6,945
5,816
213
Apr 9, 2023
#16
  • Apr 9, 2023
  • #16
You need the harness that goes through the firewall on the passenger side ro the computer. You'll need the fuel injector harness that connects with a white and a black round 10 pin connector. You don't need the harness that runs up for the headlights and stuff. Don't cut any wires. You may need the alternator and the AC compressor harnesses if you are swapping the AC. It's best to cut a deal on all the wiring you can get. That harness on that car looks a little hacked up.

The 89 5.0 harnesses should plug into the 89 4 cylinder harness by the brake booster. There are other things like the AC sub- harness and the alternator sub- harness.

What you need depends on how in depth of a swap you intend to do. If you want it to work, look, and function as a stock 5.0 you need everything. If you want the basics you don't need all the vacuum lines and solenoid stuff for the EGRVR and the emissions stuff behind the passenger strut tower.

When I did my swap I had a complete 89 convertible and swapped the harness in my 88 notch 4 banger. I made it look as stock as possible.

The most important is the harness that runs through the passenger firewall and everything connected to that harness. The alternator harness will be needed also but it's a perfect time to ditch the 2 black / orange stripe wires for a better 4 gauge wire to the positive post or starter solenoid. The starter wires will also need to be run. Perfect opportunity to use a smaller starter from the 92 - 95 5.0 mustangs.

Happy Easter....I'm tired and rambling.
 
R

Robinson

Member
Apr 6, 2023
18
2
13
TENNESSEE
Apr 9, 2023
#17
  • Apr 9, 2023
  • #17
Thanks and same to you since my swap is 1993 and so is donor , I’m gonna see what happens on the wiring harness , for straight forward swap … and try take care of the computer and get a A9L instead of this A9p , which I’m told will lead to idle issues with my t5.. I don’t like this wiring but I will clean it up and see how it works besides I may have another if price is right… glad you got some of my pictures of donor..thanks again very much
 
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