I just purchased an EFI 351w from a 1995 F250 to install into our 1979 F100 shop truck. For those that have tackled this swap, and used a stock fuel tank in the rear behind the axle, did you install a low-pressure pump in the tank and a high-pressure pump on the rail? Did you use stock pumps from the donor truck, or aftermarket?

Second, where did you install the PCM?

Third, which (if any) headers did you use?

Fourth, did you eliminate the smog equipment?

 

Keep the smog stuff if it still works. If it don't, chuck it.

 

I was more wondering about if someone did remove it, were there any changes / computer modifications required. My 1979 won't require smog inspections, and no need in having the belt spin a pump of a part that isn't needed or used.

 

A 95 truck has 1 high pressure pump in the tank 125lph. The rear tank should fit without much trouble. You can do away with the smog stuff. It will through a code but will not affect driveability. Im not sure where the PCM could go. I suppose you could sink it into the firewall as the 95 came stock. Sounds like a cool project.

 

I am doing this project right now (hopefully have it fired up today) on my '76 with a 302. The computer is going to be mounted where the glove box went because that is where the wire harness lays naturally. I got all of the efi parts (harnesses, computer, intakes, etc.) off a Mustang.
I am running a '92 f-150 fuel tank, pump, hoses, and fuel rails. The hoses had provisions for but a rear and side tank but since I am only running a rear I modified the hoses and got rid of the side tank connections.
The only thing I still have to figure out is what sensor to use to activate the gas gauge in the dash. A couple people on this forum have mentioned this but no one has said exactly what they did to get this to work.

This has been quite a bit of work and I have not rushed through it, working on it at a leisurely pace. The toughest part for me was figuring out all of the wiring that is and isn't needed, but I think I am there. Once I figured out what I needed then I bundled it all up neatly so the engine compartment looks nice. Lot's of 'stuff' under the hood now but it looks organized.

I am eliminating the egr stuff but still need to hook up the O2 sensors once I get the truck running.
There were a lot of little things I had to do (different valve covers, etc.) that you won't since you are getting the complete efi engine so that will make your swap a little easier.

Once I get her running I will post some pics and such.

Good luck

 

thanks for the replies. Sounds like a cool project as well. My current tank is new (just bought the truck a few weeks back), as the previous owner must have replaced it. It's a metal tank, and unless I have to, I'd like to keep that tank where it is for now. I might pick up a late model tank and get it set-up though. I think I'm just going to drive the truck as it is with the carbed 351w for now, and get the EFI motor built along with a new 4r70w transmission and controller. Then get everything wired, connected, plumbed, etc while on the shop floor. That way I can have everything done and worked out, and spend a day or two swapping out the old and installing the new. That way I can keep my truck on the road for as long as possible, and only non-driveable for 1-2 days.

 

I dont know about 2 days to do a carb to EFI swap

 

Yeah, that would be some long days and nights to get it all done in 2 days.

Some of the little things I ran into:
modifying the gas pedal from a rod to a cable;
getting all the wiring setup correctly, which may not be too bad if you are doing a complete swap like he said versus a conversion like I am, but still a lot of work;
figuring out where you are going to pull vacuum for all of the things that need it;
where you are going to mount all of the sensors, switches, vacuum block, etc., etc.

Even with planning the project, I will be pleasantly surprised if you get it done in a weekend, but I hope you do!

 

I understand, for some folks it takes more time, for others less. I've performed many drivetrain swaps over the last 30 years and know the basic ins and outs. I'll get the motor and transmission connected on dollies in the shop, run all wires and label them, get everything connected and routed like I want, so that when I go to do the actual install, it only takes a short period of time. There will probably be a few weeks of motor build, connecting parts, and getting everything prepped.

Once that is done, I'd start after work on a friday evening. I'll yanking the old (about an hour or so), dropping in the new (another hour or so), and getting the basic items installed (motor mounts, transmission mount and reconnecting the exhaust), measure for the driveshaft change, then call it a night. Saturday early I would drop off the shaft with a local builder to have it modified (which he can do the same day), and then it would be about plumbing the fuel lines, hooking up the fuel pump, connecting the wires and routing hoses. Go pick up the shaft or have a buddy help, and then reinstall. Sunday would be about test firing the engine, checking for leaks and fixing any remaining issues.

The majority of the prep work would be done before hand, and the actual swap and installation could easily be done over a weekend if you have experience and have done it before. I'm also in the process of installing a EZ-Wiring 18 fuse / 21 circuit harness in the truck, so that will make a few things easier too. The current wiring was partially cut up by the seller I bought from, and the rest of the wires are broken, some burned, some missing insulation, others are cracked and misrouted. I will mock it all up and get it ready, then install it a few weeks before the motor swap. That way everything I need is already in the engine compartment and ready to go.

 

I also am in the process of swappin a EFI 302 out of an 88 TBird into my 1974 F100. I would be interested in hearing more on some of the topics in this thread such as converting the pedal to cable, and how to hook the new transmission up since I am using the AOD tranny from the TBird. Any info or links to info would be cool.

 

bsiebert,
for the AOD you can read my write up on this as I have an AOD out of a Crown Vic in my truck. The Street Slammer Project Transmission

As for the pedal, it takes a little engineering. To old pedal goes through the the firewall and connects to a rod. When you step on the pedal it pivots and pulls the rod and the carb works.
The new pedal stays on the inside of the firewall and connects to a cable. When you step on the pedal it pivots and pulls the cable and the throttle body works.
So, you have to modify your existing pedal to work with a cable. I haven't found a pedal assembly from either a car or truck that bolts up to the same location as what is currently in the truck so the original will be modified. I found a picture on the web of one that someone else did but can't find it right now. Will post a link later.

You will also need to upgrade the alternator to a 3g setup. Not hard, but it is one-more-thing to do.

Sparky - it sounds like you have a plan but with all the prep work you are already over 2 days Routing the fuel lines should be done with the engine out if possible. It will make it easier. Where are you getting the lines from? Hopefully a truck since they will be routed correctly along the frame rails. Same goes for the main harness. I spent a lot of time leaning over the radiator and engine trying to reach the firewall to get things routed correctly.

All, make sure you install the fuel system inertia switch. This will cut off the fuel pump in the event of a hard crash or rollover. Mine is mounted on the back side of the dash.

Sparky - I mounted the computer in the glove box area. It just seemed to fit there. I have a center console on my bench seat so I don't really need the glove box anyway. As for the egr stuff, if you remove it you will need to get a egr eliminator (RJM Injection Tech » EGR Eliminators) so the computer will work correctly. Leave the egr mounting plate since this is where the throttle cable mounts and just block off the egr opening. You can buy a fancy block off plate for $15 ~ $20 or do like I did and take some 1.5 inch wide x 1/8 inch thick flat stock and make your own. 10 minutes and I was done.
Make sure the o2 sensors are hooked up. Mine aren't right now and the truck runs REAL rich and won't stay running since the computer isn't getting any feedback from the warm sensors. These will be installed this week. I am running long tube headers.

I think the battery mounts are different as well. I know for the Mustang harness the battery power and ground were on the drivers side whereas the '76 has the battery on the passenger side. Not a big deal to re-route, but it is one-more-thing to do

Have fun and go for it!

 

the overall work of course will take more than 2 days, I wasn't saying it wasn't. I meant that the overall downtime for the truck would be about 2 days, as I need it for work. Thta is why all the prep work gets done before hand outside of the truck. On the lines, I was considering making them myself, but if the later-model lines go in the same location as my 1979, then I'd use those. On the plates, I'm a fabricator by trade so that wouldn't be a problem.

On the computer, are you using a car engine / harness? the trucks I've seen as potential donors seemed to be routed by the driver's footwell, which wouldn't leave much room to stretch to the center of the truck from what I can see.

 

because they are cheap and plentiful and they work real well. Use which ever one you are comfortable with but when you research a 5.0 conversion everyone is using the Mustang ones, which goes with the Mustang intake. These intakes flow better than the weird truck intake.

What intake are you planning on using?

 

already purchased a 1995 F250's 351w efi from a local guy, along with the brain box and harness. I'll probably end up mounting mine on the driver fenderwell until I tear the truck down eventually for body-work. At that time, I'd fab up a box similar to the original.

 

The EFI control system will work with any intake.. factory or aftermarket, it's just a matter of connecting all the sensors. The computer is located in the drivers kick panel on the trucks so somewhere like that is where it would have to be in the project vehicle too unless you use a car or aftermarket wiring harness.. which is also possible but requires some pin swapping to make it compatable with the truck computer.
I can also assure you guys the Mustang intake does not flow better than the truck intakes, the 5.8 truck version flows about 30% better and the 5.0 truck version flows close to twice as much air.

The vacuum tree is mounted right on the upper intake on the trucks, and the whole smog system(air pump and attached plumbing and valves) can be deleted without affecting engine operation, just make sure the two control solenoids next to the coil remain connected to the woring harness. The EGR can be disabled but not eliminated, it is a pretty tidy system anyway and actually improves milage so it's worth keeping, but if you don't want to add a connection on headers for the tube simply do as outlined below. Remove the tube connected to the exhaust and put a piece of sheetmetal between the valve and intake but leave the valve connected to it's electrical and vacuum lines. The system will operate normally and keep the check engine light off but it won't pass any exhaust to the intake.