** continued from last post **
** Note to Eric Bewley, can you up the allowed post size since I'm a longwinded SOB? **
Anyway like I said before I'm guessing the complete 60º V6 engine would probably be about 100-150 lbs more than the 1.6 is. I don't think that's a big problem and worst case, getting custom coils wound is always an option.
Of course there's still the option of the 4L30E bolted to the 1.6 with the tracker/kick bellhousing and t-case provided you can find a way to trick the transmission into working without a proper brainbox assuming that the ECU for it isn't a standalone.
All 3 options have their benefits.
The V6 and 4L30E with the Isuzu electronics for an easier swap that's not too bad in any capacity and should be able to pass emissions as long as the engine is out of something as new or newer than what it's going into.
The V6 on the existing 3L30 if that pans out, should be a fairly easy swap. The fuel supply method could be carb'd or efi depending on what your emissions test situation calls for and your comfort level of working with an aftermarket ECU setup.
The 1.6 with the 4L30E might be pretty easy if the limp mode shift points are acceptable provided there's no standalone ECU for it. You probably would want to at least see about forcing the torque converter to lock on the highway so you don't get nasty mileage if you go that route. That would be easy though since it's just a solenoid you could wire up to a switch and manually lock/unlock it. Whether or not that would become a big pain is up for grabs, I'm guessing it might though if traffic speeds up and slows down a regularly. It's probably good for a road trip though where the speed is fairly constant.
You would benefit from the overdrive and the better 1st and 2nd gear ratios. The only other installation issue is that you could end up needing to play with your driveshafts since the 4L30 transmission is about an inch longer than the 3L30 is. (That's what the GM powertrain website says anyway) This would also be necessary if you dropped the whole Isuzu drivetrain in the tracker/kick although you might be able to get away with mounting the V6 slightly forward compared to the 4 cyl. The length difference might even be small enough to get away with some spacers and such depending on your suspension's lift situation rather than actually shortening or lengthening the shafts.
Other than all of the above possibilities requiring money to perform them, there's not much of a downside to any of them. Sure they're not a true "bolt in" modification like the 4 door brake calipers, but they don't look horrible as far as engine swaps go either.
The real key piece in this is the bellhousing so if that doesn't work out this is really going to be a bummer.
Actually, if the fluid passages on the back of the bell housing from a 4L30 end up being the only problem but they're close to the same as the ones on the 3L30, there's probably the option of welding up/machining out the differences. Wouldn't really cost much to get that done I wouldn't think. Alternately if they're quite a bit different there might be the option of completely machining the old ones off, welding a slab of aluminum that's the correct size and thickness as what you machined off, and then machining the needed passages back into the welded on piece. That would of course cost more but since it pretty much would just be garden variety 2 axis milling in aluminum it wouldn't be too horribly bad. If you could get a CAD drawing of the required one to them and the converted tool paths from something like MasterCAM or Surfcam to the machine shop it would drop that price a lot too since their time spent in setup would be minimal that way.
There also might be the option of welding the tracker/kick bellhousing front half to the 4L30 bellhousing back half or the 3L30 back half to a 60º V6 front half to make this work too if they're fairly close dimensionally and the differences in the fluid passages end up being too significant to work out otherwise.
Honestly, given the fact that it looks like the bolt patterns will match up, I'm feeling better about the fluid passages working ok without modifications too. Guess we'll find out.