I'm contemplating dropping an 8valve into my 1992 Samurai.  I've done a 1.6L swap before, so I'm familiar with what it involves.  However, I've never tried one that involved adapting the Samurai EFI to the 1.6L.  Hoping somebody has already worked through this.  So, here are my questions:

1.  Will the G13BA intake manifold from my Samurai's 1.3L bolt up to the G16 head (I'm assuming it will...I know the carbed ones do)?
2.  Is the throttle body for the 1.3L and 1.6L the same size?
3.  If the throttle bodies are different sizes, will they interchange between the 1.6 and 1.3 intake manifolds?
4.  Will the Samurai's ECM/electronics/harness plug directly into a complete (with intake manifold and throttle body) 8 valve 1.6?
5.  If it will plug in, is any additional tuning necessary to the Sami's ECM?
6.  If any additional tuning is necessary, does it involve anything more than a bump in fuel pressure?
7.  Anybody have a good source for a good used 8 valve (JDM, junkyards, a buddy's rig, etc.)?  I have found a few in the $500-$1000 range. 

My concern is that, if the Samurai's throttle body/intake manifold runners/etc. are smaller than the 1.6's, power will drop off at higher RPM's.  Additionally, I'm worried about the engine running a little too lean throughout the entire RPM range with the extra displacement. 

So, has anybody done this before, and if so what did you need to do and what were the results?  I'm not opposed to doing a 16 valve swap, but I would like to take advantage of the Samurai's existing EFI to keep costs down...

Found the answers to some of my own questions; still looking for others:

1.  Will the G13BA intake manifold from my Samurai's 1.3L bolt up to the G16 head (I'm assuming it will...I know the carbed ones do)? YES
2.  Is the throttle body for the 1.3L and 1.6L the same size? NO
3.  If the throttle bodies are different sizes, will they interchange between the 1.6 and 1.3 intake manifolds?  The 1.6 throttle body will bolt up to the 1.3 manifold, but since the port sizes don't match it really doesn't do any good, unless you are willing to spend a few hours grinding with a dremel
4.  Will the Samurai's ECM/electronics/harness plug directly into a complete (with intake manifold and throttle body) 8 valve 1.6? Maybe.  There were changes from 1990-1995; don't know what years had which differences, but it appears that a safe bet that engines of the same or similar year will plug right in
5.  If it will plug in, is any additional tuning necessary to the Sami's ECM? My experience is that the Samurai ECM runs the 1.6L's components just fine

A few people have done this swap and run the 1.3 ECU and reported that it works well. The mapping is different between the 1.6 and the 1.3 so its not going to run spot on. I don't think it would be too difficult a task to swap over the 1.6 and 1.3 ECUs, the ones I have seen seem very similar, its pretty easy to swap pins over on the connectors if a couple of wires are 'out of place'. What part number is your ECU? I have done memory dumps on a few 1.6 Track/Kick/Vits and also one Samurai.
To remap the Sammy ECU you would need a daughterboard, I'm not aware of one commercially available but I have produced a prototype.

I'm on the hunt for a 1990-1993 Tracker/sidekick with an 8v for a donor rig.  Shouldn't be too long before I have a 1.6 in my sami.  I hope to answer some of my own questions with the swap. 

What part number is your ECU? I have done memory dumps on a few 1.6 Track/Kick/Vits and also one Samurai.
To remap the Sammy ECU you would need a daughterboard, I'm not aware of one commercially available but I have produced a prototype.

I will let you know on the p/n in a couple of weeks.  I may be sending you a message about the possibility of modifying my ECU...

mbruce was running a 1.6l 8v with the intake from a 1.3l EFI and never got it to run correctly, others have reported the same issue.  So most just swap out all the electronics and run the full 1.6l setup.

The only way I was able to "get mine runnin' right" was by unplugging the MAP sensor (which you've already mentioned the lean factor).... and I was averaging 6MPG with it unplugged...so even though it "worked" it was never a viable solution. I also replaced the injector with a larger injector and didn't help one bit...but ur down for some ECM mods...so maybe the larger injector and an ECM mod will do the trick?

If cost is the driving factor for you and you already have the setup then roll with it and see.... but if you are still looking for the parts I'd hold out for the full 1.6L setup --  I drove 5 hours to pickup a donor hardtop 2wd geo tracker with 5-star gold wheels.  ended up selling the 5-star gold rims to Drone, took out everything I needed from donor...then sold the tracker as is to a guy looking for a hard-top.

From everything I have read/heard the "I got mine running well" means it has a cold spot and sputter here and there but runs aight.  No one will ever have a mix-match that performs as well as a full 1.6L setup....but for the costs involved that could be incurred it may perform well enough for you?  I was lucky b\c I recovered all my expenses from the sale of the hard-top.  But I live in town of 325k people and only 4 trackers...so I charged a premium -- u may live where those are in abundance and it may be tough for you to recover your expenses from the donor vehicle.

If you want a description of how it ran with the MAP plugged..... I would start it and immediately I'd have to rev it up for 15mins until it got warm...then voila it worked "well enough"...sometimes taking off at redlights it would hit a cold spot. This may sound foolish but in Tennessee it ran a lot better than it did in Louisiana -- maybe humidity, barometric pressure -- alignment of the stars? In Tennessee it was acceptable...in Louisiana it was not -- so that's when I started the fun process of testing and parts swapping and sensor buying... listened to others in the know and ended up doing the swap.  I have no sources but I have read where the "mix-match" doesn't produce the same power as the full 1.6L...i dunno --

You may be a "built not bought" kinda guy -- but the 1.6L mounts made by Petro or TT sure do make it easy... I know, I know... you can buy this from a Dodge and that from a Kia and this from a Hyundai then weld, grind, cut, drill, hammer, chisel, and boom you got one that works --

Thanks for the info; I'll just hold out for a good donor vehicle and swap the ECU into my rig. 

My reason for asking is that I seem to see a lot of standalone 8 valves for $300-$500 (no wiring harness/ECU).  Just trying to find a way to capitalize on one of these deals.  They are fine if you are going the weber route...but I won't ever wheel a carbed rig again! 

 I drove 5 hours to pickup a donor hardtop 2wd geo tracker with 5-star gold wheels.  ended up selling the 5-star gold rims to Drone, took out everything I needed from donor...then sold the tracker as is to a guy looking for a hard-top.

I do love me some gold!

OK; I finally got my hands on a complete running donor vehicle a week ago.  I have swapped the 8 valve into my Samurai, and completed a little bit of experimenting.  My 1.3L ran perfect prior to the swap, and I thoroughly tested the 1.6L prior to installing it so I knew I was going into this project with good parts.  I put a new timing belt, plugs, cap, wires, rotor, and adjusted the valves on the 1.6.
I started off by dropping the 1.6L long block into my Samurai, then I bolted up the Samurai's intake manifold/TBI.  It started just fine, but ran rough at idle, with occasional misses.  I double checked cam timing, ignition timing, fuel pressure, etc.  I spent about an hour driving it around.  I was a little bit disappointed with its performance.  Although the engine was noticeably more "torquey" than the 1.3, it really fell flat at higher RPM.  My top speed was almost exactly the same as with the 1.3.  But the REAL thing that bothered me was the stumble on acceleration at low RPM.  I stalled it at least 4 or 5 times during my test drive.  The hesitation was too much for me to live with (I'm pretty picky about how my vehicles run).  I had planned on running it this way for a week or two, but I knew I would never be satisfied with it.
So, I pulled the Samurai intake manifold off, and dropped the 1.6 intake on.  It doesn't plug in perfectly; I had to bypass the IAC valve, and temporarily bypass the evap system (the samurai system is temperature controlled, and the sidekick is controlled by the ECM).  I used the harness off of the the Samurai's manifold (easier than trying to adapt the sidekick harness).  After it was installed, the 1.6 ran perfect.  It started, idled, and drove just like it did when it was in the sidekick.  I'm still working on getting some mileage numbers, but it seems like the Samurai ECM has no problem with the 1.6L's manifold.  I plan to run it this way for a few weeks, and then attempt to swap in the sidekick's ECM. 

UPDATE

I have been running the Samurai for several months now with its current setup:

1.6L 8 valve with the sidekick intake manifold, throttle body, and associated sensors.  I'm running the Samurai distributor, coil, and ignitor (the ignitor is different on the sidekick, and won't plug into the Samurai's harness).  The IAC valve is capped off (the Samurai ECU keeps it open too much, resulting in a lean and unstable idle).  The TBI butterfly valve is opened up a little bit for a good idle.  I'm running the stock 1992 Samurai ECU and wiring harness. 

My Samurai is quite a bit heavier than the average one (exo cage, winch, and other armor).  I've had the Samurai on all sorts of terrain, from Sea level here at the coast to over 14,000ft. in Colorado, with a bunch of off road and street miles logged.  It runs great...more low end torque, more high end HP, added about 20 MPH to my top speed (about 80 MPH on flat ground) and it will hold 55 MPH on a 5% grade (drops a bit on steeper grades).  It gets about 15% better fuel economy than the 1.3L did that I pulled out. 

I have no complaints with this setup, but I feel that slightly better economy and maybe a few extra HP are possible with a proper functioning IAC valve and proper fuel mapping with the sidekick ECU.  So, in the interest of testing, I pulled up the pinouts for both the sidekick and Samurai ECU's and went to work.  (see attached documents)
After comparing both schematics for about 20 minutes, I determined that there were 7 differences between the 2 wiring harnesses.  All of the important things were the same (power supplies, MAP, TPS, CTS, etc.).  The sidekick had the fast idle power steering input and EVAP system controls that the Samurai doesn't, and a few other things.  But, I thought there was a chance it might work without modification. 

The connectors between the two ECU's are interchangeable, so the sidekick ECU plugs right into the Samurai wiring harness.  I plugged it in and turned it over; it would fire and then immediately die.  If I continued cranking, it would crank for about 1 second, hit on about 4 cylinders, then go back to cranking, then hit on 4 cylinders, etc.  I plugged the ECU fuse in and got code 12 (meaning the ECU was powered up and operating, and had no trouble codes).  After doing a bit of troubleshooting, I discovered that after a few seconds of cranking, code 41 (weak or no spark) came up consistently.  I spent some more time looking, and realized that the tach signal on the Samurai harness went directly to the instrument cluster...but in the sidekick it went to pin A1 on the ECU.  Pin A1 on the Samurai harness was unused.  So, I pulled one of the connectors out of the sidekick harness, inserted it into the Samurai's A1 spot, and ran a jumper from the tach signal wire to the connector.  Bingo!  It fired right up and ran perfectly, no trouble codes. 

I intend to run the Samurai this way (with the sidekick ECU) for the next week or so and see if I notice any driveability/economy issues.  I'll be sure to report back here with my findings!

Haven't been able to run a full tank of fuel through it yet, but I did get the IAC valve working.  It makes a noticeable difference in how the Samurai drives and idles.  I am hoping for a slight increase in fuel economy, as it will run significantly more lean at idle now.  The engine also coasts down more slowly than it did before (less compression braking due to the IAC valve letting air by the butterfly valve). 
I haven't noticed any "seat of the pants" change in power; acceleration and top speed are about the same as when I was running the Samurai ECU. 

PM sent.