1973 Fiat 128 Engine Swap Part 2

Red128

Daily Driver
So....I have removed the engine from the 85 X. It’s currently at the shop getting cleaned and adjusted. I would like to keep the fuel injection system and install into my 128. Does anyone have a step by step on how to go about this or what parts I should be removing from the X? Engine removed, transmisión removed, fuel pump removed, ecu with wire harness removed. Wire harness running from engine bay to dashboard/cluster still installed (Looks like a pain in the ass to remove).
 

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There isn’t a step by step for this, unfortunately you need to churn through the two wiring diagrams of the two cars you have to get what you need. It is part of why it is so important to know what year your 128 really is as the wiring can be vastly different based on the year of the car during the years this car was produced massive changes took place in regards to safety and emissions systems so there were big differences between some years.

I would read back through the front drive part of the forum and become a member of MiraFiori as some of the old time members there did have 128s and may be able to help you but remember those cars and those members likely used carbs in hopping up their cars so don’t expect them to give much input on fuel injection.

We spoke about just putting the carb and it’s manifold into the 128 with the 1500 to get the car on the road and fix the other things this car will inevitably need. Putting the injection system into the car will be a bigger, fussy job and given the quality of the wiring I see, you likely have wiring repairs to make for it work reliably.

I think the following two posts by me cover much of what you have asked for:

You do need all of the wiring in the X’s spare tire well. There isn’t much of the rest of the wiring harness you need from the X, so you won’t need to pull wires all the way back to the instrument panel (if your 128 doesn’t have a tach you may wish to add a wire but you shouldn’t need the exact wire from the X as on a 128 it is a much shorter wire). What you do need is the wiring from the fuse box to the double relay and then the wires from there to the various components and the ecu. All the ignition related wiring in the engine compartment, the wire from the ignition is the same so you won’t need to go back to the ignition switch.

You will want to ensure the 128 side of things remain 128 to make it easy to resolve wiring/mechanical issues and the fuel injection, electronic ignition wiring to remain as much like the X as possible so you can easily use the manuals and expertise for the fuel injection that does exist on the forum.

Looking forward to seeing things start and we can help you over the inevitable humps and bumps.
 
I still say (and agree with Mr. Mead) that you should initially go with the carb off the 128 just to get things running. If you spend the next month or so installing the FI and the motor does not run we won't know if it's the FI or maybe something in the motor itself.

Having stripped the FI stuff from manty Xs, I know the harness is stand alone. Just find out where it plugs into the main harness and see if you have equivalent sources in the 128 harness. You don't necessarily need the wires that go up front to the dash wiring but you do need to trace those wires to see where they go.
 
So, the intake manifold is going to be a bit awkward. If you can, see if anyone has a yugo FI intake manifold for you, will help in routing airflow as the X one will put you right into the radiator. Doable, just awkward.

I know others are saying to go with a carb, but I say go for it. The FI harness, as already indicated, is stand alone. Just having to figure it out is the hard part, but nothing too weird, with it. First gen FI is pretty simple compared to later.
 
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So....I have removed the engine from the 85 X. It’s currently at the shop getting cleaned and adjusted. I would like to keep the fuel injection system and install into my 128. Does anyone have a step by step on how to go about this or what parts I should be removing from the X? Engine removed, transmisión removed, fuel pump removed, ecu with wire harness removed. Wire harness running from engine bay to dashboard/cluster still installed (Looks like a pain in the ass to remove).
I am doing the same i will be using the mega squirt system
 
I am doing the same i will be using the mega squirt system
No clue what the Mega Squirt System is ? I just recieved my engine from shop yesterday. I will be attempting to build this weekend. I say attempting because I have no manual.
 
Mega/Micro Squirt is a stand alone injection system which can manage fuel and ignition (at the least) for a motor. The MicroSquirt system is capable of dealing with all an older car like a Fiat SOHC engine. There is easy to use tuning software and both systems can use a wide band O2 sensor to give feedback for managing the system.

MicroSquirt is simpler, cheaper and likely the best solution for this car. The trade off between these two systems is one can deal easily with the injectors used in the LJetronic system. To use them on the MicroSquirt system you have to add resisters inline to the injectors or change to high impedance injectors which were used on the later variations of the Bosch system, mainly on BMWs. The cost difference between the two systems could be eaten up by having to get new injectors If you don’t want to go with resisters to change the impedance.

There are a number of modern coils which can be used with these systems, a good one was used on Mk4 VWs and can be found in junk yards across the nation or new cheaply as they are still being produced for production cars in China.
 
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Good news. How did everything turn out on it?
Well for $1,100 bucks they cleaned and magged block, bored and honed cylinders, polish crankshaft, cleaned and installed pistons and rods, valve adjustment. Pretty expensive. That didn’t include the $200 extra I spent on the rings and gasket kit. Figured they could have atleast installed the head and timing belt for that price. A little upset to the fact I left bolts and nuts on the head so I wouldn’t lose their places because of their different sizes and they gave them back to me in ziplock bag :/ Now I need to order a book to start building it back up.
 
Okay so I’m in the process of installing the 128 oil pan onto the x engine but it doesn’t sit all the way down. It’s hitting the oil pump from the 128 and or the oil return pipe.
 

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You will need to either use the X1/9 oil pump and pan, or the 128 oil pump and pan, but not mix the two. This is due to the difference in angle for the engines/pumps/pans. Since it is going into a 128, best is to use a 128 pump and pan. One of the 128 experts here will need to say if it is the entire oil pump or maybe only the pickup portion than can be swapped - I'm not that familiar with the 128 pump.
 
You will need to either use the X1/9 oil pump and pan, or the 128 oil pump and pan, but not mix the two. This is due to the difference in angle for the engines/pumps/pans. Since it is going into a 128, best is to use a 128 pump and pan. One of the 128 experts here will need to say if it is the entire oil pump or maybe only the pickup portion than can be swapped - I'm not that familiar with the 128 pump.
It’s weird because the oil pump from the x has the same part number as the 128 and they are exactly the same size including the pick up part. But the problem wasn’t with the pump it was actually with the oil return pipe. It’s too long where it doesn’t let the pan reach the block and mounted at an angle where it doesn’t let the pan align with the block. I wonder if I could just cut some of it?
 
It’s weird because the oil pump from the x has the same part number as the 128 and they are exactly the same size including the pick up part.

The pump body & gears are the same, but the pickups are not (different horizontal angle of the bellmouth part).

But the problem wasn’t with the pump it was actually with the oil return pipe. It’s too long where it doesn’t let the pan reach the block and mounted at an angle where it doesn’t let the pan align with the block. I wonder if I could just cut some of it?

The X1/9 pipe is longer due to the different angle of the X1/9 oil pan floor (in relation to the side walls).

On your X1/9 1500 engine in a 128 chassis, use the 128 oil pan, the 128 oil pump pickup (or the whole 128 oil pump) & the 128 oil return tube. These parts are all meant to work/fit together.
 
Concur with Jeff. I have made plenty of these conversions and the 128 pan will fit with not problem when the 128 parts are installed as indicated by Jeff. Also, don't forget you will be using the 128 flywheel and starter.
 
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