Keep it simple.
If you're going to rebuild, I would just punch the cylinders out to the next oversize, get forged internals (pricey) have the heads ported and flowed to handle other improvements. Get the exhaust completely redone and match it with a fresh tranny at the same time. I would also get a custom ground cam and new rockers/valves. Then you can improve your ignition and fuel delivery systems. A chip and internals work/exhaust in combination would work best. It would also be reliable because you didn't go crazy with the rebuild. I said to use forged internals because you can then add a small shot of nitrous later if you desire and will be much more confident in the engine being able to handle the extra kick. Overall a nice improvement in power. mpg may suffer a touch and you'll have a solid running car for another few years. When you get the tranny done, I would get any additional heavy duty internal changes that may be available or shift kit, etc to help it with the new load. They are the weakest link. Of course if you don't have one already, get a STB to improve the handling too.
Money no object?
For that I would build an engine cradle that allowed me to swap in a 302 (that's 5.0 for the Bob, lol). Pull off the exhaust to free up the tunnel, buy an aftermarket rear subframe, mount it with a Ford 9" rear, (mini-tubbing optional). To make the swap the battery and fuel tank both have to be relocated to the trunk. A 5-spd would be sweet but to keep it simple, just match the 5.0 with a C6 tranny and go. Upgrade the suspension up fron to deal with the additional weight/torque of the new motor. enjoy. (Was going to be my ROTB2 project before I got sent to Iraq). I've talked with several aftermarket chassis companies who said it would actually not be too hard on a Taurus because there is a fair amount of room underneath compared to some of the others they've done. There are pictures of the whole process on the web somewhere. It was a V8 conversion for the Contour or some other car smaller than the Taurus. (I forget which)
:chili:
