Choosing the fate of a poor SA22C
 

So I'm in a bit of a pickle. I have the choice of either getting an NA S4 13b rebuilt or buying a turbo motor for a '79 RX-7. From a cost and power prespective, buying an already assembled motor would be cheaper than paying a shop to piece one together. The one thats in bits and pieces has been ported, but a turbo motor would be more flexible in making power, not to mention all the great turbo noises.

I'm not looking to make monster HP so the NA motor would do me just fine, but when it's all finished it might not run that well. From what I was quoted, I could get a get a turbo or even twin turbo 13b for the cost of rebuilding the NA.

Now, when it comes to actually installing the motor should I stick with an S4? Or will an S5 motor bolt up to the trans of the 79? I read somewhere there's some flywheel trickery involved in swaps, but I think the one I have is compatable.

And just to be as informative as possible here's most of what needs to be installed on the NA motor:

12a front cover, gsl-se oil pan, oil bypass valve, pulley hub, pulleys, intake manifold and throttle body, headers, wiring harness, oil metering pump + lines, replace braided oil lines, water pump, ac compressor, air pump (which I don't have), alternator, crank angle sensor is a bit worse for wear, intake acuator, there's a chance the needle bearing by the front counterweight could be misaligned, and last I looked a stud for the headers was broken.

Whats a guy to do? :(

The decision is ultimately yours.
You can get Guys on here telling to Drop a Turbo engine in it,blah,blah blah..BUT in the end you are Paying for it..and it is YOUR car.
With all "modifications" comes a price.Aftermarket parts,fitment issues,etc.They all add up.
If you do your research you can cut that cost down.If you use your imagination you can make something work.
You may not get the Exact answers that you seek in this section but the INFO that is already available on this Forum will give you the personal option of doing the car to what YOU like.

NA motor. Simple. Less clutter. Better sound.