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mod swap


New Member
Step-by-Step Guide (foxbody) 4.6 SOHC to 93 GT

posted Thursday, April 14, 2005 6:35 PM by modular93fox
Basic dismantle :
Remove the obvious components: exhaust, driveshaft, grounds, and fuel and a/c line to compressor… Unhook the main harness connector from the inside of the car connecting to the PCM. There is a relay on the upper most part of the PCM retainer, and a clip that holds the harness to the frame which makes it a bit difficult to remove, care is needed when pulling on the harness from the motor side (when pulling on the harness be away of the hole opening, so you don't cut the wires against the edge). You can either leave the harness on the motor, this way there's no chance to break any connectors, or remove the harness completely. Basically remove all necessary lines/connections that will prevent you from removing the motor/trans. Remove engine/trans as an assembly (I left the old radiator in the car and left the a/c line that ran from the condenser to the evaporator) once you remove the motor transmission, you can get a better grasp of what's next. You can start on the detailing of the engine department or you can start on the brakes.

K-Member Install
Now is the right time to swap k members, I chose the AJE k-member and spring perches to retain the stock coil springs. Basically remove the brake components, spindle and strut as an assembly (an impact wrench is recommended to remove the strut bolts, or at least in my case it was needed) once both sides are removed you can remove the control arms, once removed, its time to unscrew the 8 bolts holding the k-member on, save the stock fox rack and bushings because the will be reused on the new k-member. Once removed, install the new k-member (with the spring perch installed) and the bolts semi loose, until you all 8 are screwed in. Follow the k-members install instructions to ensure a square fit.
Reinstall in reverse order with the exception of the rack, install that last, reason being is you can't tighten the control arm bolts because the rack is in the center of the front control arm bolts. As far as springs go, it's not a walk in the park, at least with the tool I rented from AutoZone. After installing (fighting) the stock coils in, the car had a case of extreme 4x4, even after I installed the motor and transmission, it didn't sit down any! I proceeded to cut 2 coils off each side, thinking that would be ideal, well it turned out too much, it looked like the Sportline kit was installed. I then got a pair of springs off of a friends 01 GT (same springs) and cut them 1 coil, just right. Finish the install by either reusing the stock fox spindle or upgrade to the sn95 spindle…if you choose the sn95 spindle you need to either a) use a hardened spacer or spacers totaling .033 inches so when you tighten the crown nut down, the cotter pin will still reach the crowns or b) replace the ball joints with the 94-95 style ball joints (I chose option b simply because replacing the ball joints seemed more logical, and I had no idea how much life is left in stockers) . Finish installation by installing spindle/strut into ball joint and install springs and connect the pitman arm to spindle, adjustment will be needed, if you look closely, the tires will be pointed outwards a bit, simply adjust it so both are pointing as strait as possible to minimize tire wear before you get it aligned.

Brakes - Hydroboost setup
I chose to have power brakes so I decided on hydroboost. For those who don't know, its run off the power steering pump, not vacuum. First remove the brake lines from the proportion valve and master cylinder (best bet is to use a pair of vice grip pliers. It works great and doesn't round the nut) . Next remove the steering column, I found it is next to impossible to remove the pedal assembly with the column installed, so it needs to be removed. There are 4 nuts that hold the column up and then the bolt that connects the steering shaft to the rack extension (engine bay area) then remove column by pulling and having a buddy hit the edge of the column with a hammer & large screw driver combo to help loosen the fit. Once removed commences the disconnecting process… unhook the connectors next to the clutch, then the brake and last one is next to the gas pedal. Remove the clutch cable that is wrapped around the quadrant, and start removing the 4 bolts (I believe they were 13mm which requires a deep socket, along with a pair of long extension and a swivel to make it even easier) . Once all bolts are removed, you can now remove the power booster plunger from the pedal, and remove the assembly from the engine bay. Remove the stock pedal assembly. You will need a template so you can drill the new 4 th hole (in the lower left corner if you were looking at it) , in my case I needed to bore the center hole out a bit, only in the upper ½ about ¼ of an inch, fitment was greatly improved. A spacer plate is needed to align the upper stud with the pedal assembly. I had a chunk of 3/8 aluminum lying around so I used that. I wouldn't recommend steel simply because it would be harder to cut and drill through. Once you have placed the adapter in between the firewall and pedals, mount the hydroboost brake assembly together (a buddy would make this process a bit easier, also make sure you have that rubber boot that goes around the plunger in place before you get to far) now you are ready do plum the lines from the master cylinder to the proportion valve. Best thing to do here is get a pair of lines from the auto parts store *bubble flare* and bend them accordingly and complete the other end by cutting and double flaring them. You can rent tools needed from some auto parts stores such as AutoZone for free. Practice makes perfect so practice before you do the final lines… you will also need to cut and flare the 3 rd brake line and tap it into the other line, see pictures. Once you run everything is buttoned up here and your front brakes are almost squared away. Last part of the front brakes are the passenger side fitting. If you choose to keep the 4-lug, skip this step. 94-95 spindles can be used here, and you can use the 94-95 style calipers and corresponding flex lines, or use the 99+ calipers and flex lines (like I chose) . See link for info on fitment and modifications to spindle here: http://www.sn95brakes.com/sn95brakes.php (site has great diagrams & pictures). If you choose to go this rout, you need to do something about that passenger side fitting, this fitting is larger than the driver side. I chose to cut and flare it and put the correct fitting on it. Check and double check there aren't any leaks…. it is impossible to cut and re-flare the lines in the engine bay once the motor is in! Finally, cross off the front brakes because they are done

Hydroboost Lines
Run all of the power steering lines/hoses so the only one left is the one is on the power steering pump that will go to the hydroboost itself. Running these lines before you install the motor will be helpful, I didn't have all the lines and I installed the motor, but it's possible to run them after the motor is in. The clearance between the metal adapter line and the oil filter is practically on it, which it is. I would suggest that a rubber line is wrapped around it and zip tied or clamped (to prevent the two from rubbing a hole in each other. Once the lines have been tightened the motor/transmission assembly is ready to go in. I thought there was a problem, the metal hard line adapter in the rack seems to wiggle a bit even when tightened down all the way. After driving the car there is no leaks what so ever, I would hav assumed that things that wiggle leak?? Go figure.

Motor / Transmission Install
The accumulator needs to be removed in order for the motor to go in smoothly. I would strongly recommend that you take off the driver's side motor mount, this will allow the motor to drop in where it's supposed to 100 times easier. Once the motor/transmission is in the car, you will notice it is a snug, but not impossible fit, just some persuasion is needed to coax it to the mounting plate. Re-install the motor mount and temporally place a jack under the car to support the transmission. Leave the motor mount stud nut loose for now.

Transmission Mount Relocation
I would recommend drilling out the spot welds before you put the motor and transmission in simply because there is more room to work. Drilling out spot welds is a … nicely put a S.O.B… there are spot weld drill bits, but they weren't going fast enough for my pace… in the end, I got a marker and marked all the spot welds that I could see, marked them, and drilled them out, starting with a medium size drill bit and working my way up. Once you think you got them all, get a chisel and bang away. In my case, it got a bit hairy, the chisel would go through the floor board, and in 1 spot, I missed a spot weld and kept on banging away and took a chunk of my floor board off, it's an easy fix, but just letting you know it's not an easy walk in the park task. Once removed, clean up the brackets, smooth them out with a grinder, and prep them for the new install. Looking at the bracket, I used 3 screws and 6 washers per side to hold it in place until I could get it spot welded. See picture – add picture


I've created a detailed wiring schematic that should get your car started just like mine did with a modified dash harness (if you choose to use the new style cluster) or get a hold of the 2 plugs by the pcm (see diagram) and wire in the power wires. (Insert link for pdf file, in its finishing stage 4/14/05)

Radiator mounting:
Radiator sat in the same location, didnt do any mods to the bottom at all. The top I modified a pair of sn95 radiator brackets (cut and welded) to make them hold the radiator. (See Pictue uploading soon)

Coolant Mounting:
Used the stock support rod and bolted it to the tank, and sat the tank on the fan assy, where the hump of the fan shroud mates with the grove on the tank. then I fabed up a pair of brackets to hold the front 2 bolts. (See Picture uploading soon)
Fuel Rail:
Temporarily I chose a return style rail off of a 2000+ crown vic, e-bay style for 15 bones in practically new condition. It was a starting point and saved me $160 from the dealer. Fitment was perfect, it matched all the holes perfectly, as far as the outlet location, well those are not in the most desirable location, they dump out right next to the oil filler, not a complete disaster, its doable, but once testing is done, I will be getting the 96-98 style rail which puts the fuel lines at the back passenger side of the motor (ideal location) . The Russell –an fuel rail adapters fit like a champ, they simply press in (by hand with a little force) .

Fuel Lines:
Add picture of how the tube sleeve and nut go together
Add picture of finished lines

Written by:
Clint Collins
1993 GT upgraded to a 03 GT standards


New Member
Swap Build Sheet (foxbody)

posted Thursday, April 14, 2005 6:36 PM by modular93fox

From donor car needed: Additional/optional:
Motor / Transmission Hydroboost brake system & all lines & adapter
Motor harness 4.6 pedal assembly (or modify 5.0 break pedal)
Mass airflow sensor and intake tube
Calipers w/stock flex lines & matching banjo bolt (if you upgrade to the PRB calipers)
Driveshaft input yoke
Stock 4.6 motor mounts
Stock 4.6 H or aftermarket X pipe
Stock 4.6 radiator & cooling fan
Stock 4.6 radiator hoses
Stock 4.6 coolant tank and support rod
Stock 4.6 accelerator cable
All engine related sensors (exception purge valve)
Aftermarket Additional / Optional:
-an fittings Russell -6an & -8an Ford EFI rail adapters
Braided fuel line -6an & -8an
190lph fuel pump
4.6 k-member w/ mounts 1" foward (had to slot the AJE-3020)
Spring perches for k-member (springs need be cut 1 coil)
Stock 5.0 steering rack and bushings
Stock 5.0 cross member (just relocated)
Stock 5.0 transmission mount
Stock 5.0 clutch cable (manual only)
Stock 5.0 after cat exhaust
Extra costs:
Re-worked 4.6 h-pipe (to conform better)
Possibly shorten driveshaft/install new yoke
Tune if you go returnstyle and delete rear o2 sensors/purge valve and misc. sensors
Upgrading to 5 lug (if you choose)
See article on axels, and sn95 spindles @ http://www.sn95brakes.com/sn95brakes.php
5 lug wheels (4), 5-lug axels (2), 5 lug spare tire (1), sn95 spindle (L & R), wheel hub (2), front rotor (2), 5 lug drums (2)
Cross member mounts
Power brake hole 4 th hole
3-2 brake line “t†(cut and flare)
Passenger side brake line fitting (cut and flare)
Radiator mounting
Coolant tank mounting


Well-Known Member
wow twoll86 very nice and thank you for sharing with everyone and on the first post can you fix the link...

Thanks again..
Trying to make this a very informative website..


Active Member
Maybe its just me but none of the pictures are showing up on the thread. any way to fix the links?
This is the missing link of information I want- I would love to have that detailed wiring schematic for the modified dash harness.

I've created a detailed wiring schematic that should get your car started just like mine did with a modified dash harness (if you choose to use the new style cluster) or get a hold of the 2 plugs by the pcm (see diagram) and wire in the power wires. (Insert link for pdf file, in its finishing stage 4/14/05)
FYI I was able to get the pdf file. If anyone wants a copy PM me your email address.

Also to be clear this is for a 2003 SOHC engine into a fox car, but the info should work for DOHC cars as well and be very similar for 99-04 cars- with the exception being the 03-04 cobras. They may differ a little.