Buying an FC with a blown motor....
 

Right now I face two different options both dealing with engine replacements.

On one hand I could get an NA RX7 and drop in a tuned NA rotary motor. How much do these usually cost (sold from pineapple racing?) Can you buy a more powerful NA engine that will pretty much swap directly into its predecessors place (no tranny, drive train, or electrical modifications). If not, what would I usually have to modify?

On the other hand I could get a TII and do pretty much the same thing. Again, avoiding as much custom work as possible (I pretty much just want to swap in something that will just plug in and go).

I'm trying for reliability, but I do want some power. I know the NA engines are reliable, but they ardent all that powerful, and there's not many things you can do to really crank the power out of them. That’s why I’d want a more powerful NA engine. All I can say is I take very good care of my vehicles, so whatever goes in I will very rarely beat on or push to the limit. What would you suggest?

Get a street ported N/a engine that will give you a little bit more power. All 13b's basically bolt on to most transmisions except the REW and RE 13b's. I think you could get one for 2-3 thousand

How much power would I expect a street ported NA engine to put out? Will it pass TX emissions (tested on car class, so they're geared to handle V8s). Where would I get one from?

Uh I have seen estimates in the 20-25% increase in horse poower stock s4 has 146bhp and an s5 has 160bhp so add a 1/5 to either. There are many places like pineapple racing, mazdatrix, mazda itself(not ported though), amd others I can't remember. I think it would pass emmisions I don't see why not but you never know. I did not notice you were also from TX I have a cousin up in Houston. if id does not just find a place that you can bribe the guy or come down hear to Laredo it is only a six hour drive once a year I have neve seen anyone get tested for real here they just make sure the car is driveable and safe. A twenty is always a good thing to hand out though.