One way to Fuel Inject a 4 Cyl!!

[Bill usn-1]

This may take a while to get it all loaded up but here's a start.


The conversion was done on a 1962 152ci 4 cyl.





To start with it had already been rebuilt by a PO.
It had a 1 barrel carb.





and a Holley points distr. The Delco was is the box of parts.


The first obstacle.....

Making the TB adapter so it will clear the thermostat housing and still give a direct shot for the throttle bore.
I used 1/4" steel plate and 2"OD steel pipe. The carb is 1 9/16 bore and the TB was 1 5/8 so they are real close.




















Now for the next hurdle!!
Spark!!!
Started with a 4cyl holley dist.
I performed the normal conversion but instead of making the slot where the old points wire went through I made the slot closer to the vacuum can so the wires inside would follow the dist and not hit the reluctor.
I used the V8 reluctor and removed every other fin.
Since I have a welder, I spot weld the advance shaft to the main shaft against the stops under the plate. That way I don't have to worry about it coming loose down the road, not that it could if you put the clip back in the top!!









Here is the next item to deal with.
Since the 80 does not use vent lines you have to either plumb new holes into the tank to use for a return or put a piece of pipe in the middle of the fill hose with a hose nipple on it so the return will go to the tank. A simple piece of exhaust pipe with a 5/16 nipple welded on it.
OR
I am going to try something different. Most articles I have read advise against it but we all have to try.
I am going to use a surge tank to recover the unused fuel from the TB as it returns. I will also plumb the main fuel line into the top so it will draw fuel as needed.
The pump feed will come off the bottom.
This will ensure that even while off roading or bouncing, you will not suck any air caused by the fuel in the tank moving around away from the pick up.

It's a simple set up using 2 1/4 exhaust pipe and I made the end caps out of some sheet metal I had. I cut them out with a 2 1/2 hole saw and welded them up. Drill the 1/2" holes for the 1/4 pipe nipples and welded them in.
If only I had a new welder!!! and knew how to use it.
I plan to mount the switch valve above the surge tank to act as a trap for the fuel.
I plan to weld the round end of a 2 1/4 muffler clamp to the frame and just put the tank in place and tighten the clamp up to hold it.

First, this is why the 80/800 rots out the quarters!!!






Here is the components that make up the surge tank.





Here it is mounted. As I said , I just welded the top of a muffler clamp to the frame and clamped it in place. The lines still have to be clamped along the frame,
You can see the feed lines from each tank going to the sw valve. Only need a 3 port since it doesn't have to sw the returns.
The pump is mounted low on the frame to prevent it from having to pull fuel up hill.






You can use a 6 port sw to switch the fuel and the return all with the flip of 1 switch. That's how I do my motor home and not use the surge tank at all.



My only hesitation with the surge tank is trapped vapor in the surge tank. I will need to run it long enough to ensure it is stay full and if you run it out of gas, will it self prime? Well it worked fine but it never ran out of gas so I still don't know if it will self prime once empty?

I think the easy way to solve the returns to both tanks is to use the 6 port valve and run the returns to a piece of ~1 1/2" exhaust pipe with a nipple welded in the middle of it. Cut the tank filler hose in half and insert the exhaust pipe in the middle. Then hook the return to the nipple.
fast and easy!!

Here is how I added a return to the tank for future use. Just brazed a nipple right onto the filler neck. Pointed it towards the tank so it would not flow towards the cap!





I think the fuel line from the tank is about 1/4". for a 4 cyl this may be fine but I would limit the length. The plan right now is to replace as much of the hard line as possible. We still have to pull one tank out and check the size of the pick up.
Should be able to use regular 5/16 or 3/8 steel brake line to replace the small 1/4.

Here's what we did.
It's all in 3/8 steel now.






We made a new plate and brazed the tube to it.




Then we made new gaskets and put it back together.





Almost there.
Wiring!!!!
Follow these guidelines! Wiring Click!

These things are really small. I can make another harness with what I have to cut out!!



I use the marine and aircraft style butt splices. They have the crimp sleeve with a heat shrink tubing over it. Make them environmentally sealed so the elements do attack the connection.
I tailor each of my harnesses to the vehicle. There are a lot of ways to set it up and each guys scout is a little different so I don't make mine a generic length.
I end up cutting and splicing just about every wire.
It may sound like a lot but by the time you are done going pin by pin with the wiring instructions up in the post, it's not that bad.
Maybe 25 total.


I strip the harness down, plug each sensor I'm using into the harness then go pin by pin and trace each one and mark it with tape.
When done I take out the unused by removing the pin from the plug just in case I really did need it.

Here's the harness before I start snipping. All the sensors are plugged in and the outer covering and tape is removed!



Here's the harness after I have removed the excess. Note the sensors are still plugged in!



Here's what I pull out before I even set it in the scout and tailor it down!




Then I drill the hole in the firewall and lay everything out in the engine compartment.
I pick a spot to mount the relays and the various sensors.
When I have it all as I want it, then I start cutting the excess wire length out.
I try to do it 1 wire and 1 sensor group at a time so I don't tie sensor grounds with system grounds.
As I get them done I tape them up together to form 1 main harness.


A couple of things I found on the initial test run.

First, since the 1 barrel throttle is opposite of the 2 barrel I found out that the 2 outside wires on the TPS connector need to be swapped so it will send the right resistance to the ECM.

next, since I am trying to run the V8 system on a 4cyl with 1 inj it takes a lot of changes to the fuel tables.
......................
It's getting closer. You can compare with the pic above.
I'm a little rich on the bottom but she pulls pretty good.




UPDATES
After talking to a couple guys that are also into FI. They mentioned that the inj's on the V8 TB alternated in firing.
I had watched the cones many times but never really noticed.
So we talked about using 1 inj or 2 and how I wired this one.

Well after we talked I thought more about it and decided that if the ECM alternates the firing of the inj's than you should be able to hook both wires to the same inj and fire it with both!!

So that's what I did.
I hooked D14 and D16 together on the 1 inj.
Then I reset the BPW and went back to my basic V-8 fuel tables.

The adjustments needed were very small!
Before I had to almost double FL2 fuel table on top end to get enough fuel to the motor and then lean out the bottom end.
Now it's straight down the line on FL2 and FL1 wasn't that far off.

So she is running good!!


Another option would be to use the 2.8 TB or even the 4.3 TB.
I think the 2.8 would be just about right!! They are 2 inj TB's vice 1 like I used but the bores are 1 3/8. The 4.3 is 1 11/16..
The 152 is a 2.5l motor since it is half of a 304 at 5.0l.

Here is an adapter that may make things easier.
You can bolt a small plate on top to mount the 1 inj or the 2 inj TB to!!

adapter


Then bolt something like this Holley adapter on top or the Transdapt 2204!!
Or better yet...make your own out of a piece of 1/4" alum!!!

[ldo_marlin]

Bill - What ECM did you use for this conversion? 1227747?

[Bill usn-1]

Yep!!..........

[ldo_marlin]

Did you have to change the # of cylinders, BPW constant in the bin? Interesting that you had to splice the injector wires together.

[Bill usn-1]

When I first started running it I only used 1 inj lead and set the cyl to 4 and the BPW based on the engine size.
I was having all kinds of fuel issues. Basically I just could not get enough fuel into the motor and I was having to max out the FL1 table.
So after seeing the alternating (batch) firing of the injectors, I just went back on the BPW and the stock fuel tables and then started tweaking from there.

Even the stock V8 tables would run the engine. So as long as you can log data...you can adjust it!!

BPW you can work either way. I would say just leave it at the V8 135 setting since you are basically running 2 injectors now.

The other way would be to simply bolt the 2.8 throttle body on it and tune as normal but with the cyl select to 4.

[ldo_marlin]

I agree on the 2.8 tbi. Very slick setup using the 747!!!
Otherwise, the ecm from a 4 cylinder has very little support on modyfing bin and logging.