M113 vs M113k ?
 

Diffrence between NA M113 and supercharged M113K?
The supercharged one has lower compression ratio, but how about the connecting rods? are they weaker in the non supercharged enginge? or is it the same?
How much power would a boosted NA M113 take with a turbo before breaking?

To the best of my knowledge in addition to lower CR the m113k has forged pistons but normal connecting rods. Same as the m112k in my c32amg.

Several people have claimed around 600HP on the 5.4L M113 with Kleeman S/C and headers, without major problems. M113 is stout AF, but if you lean it out you will annihilate the pistons. One turbo build I saw online somewhere used Megasquirt and converted to a speed-density (MAF-less) setup that they claimed was very stable. I think it was a W203 or 209 with the same engine. The major hurdles to running a turbo(s) are packaging in the engine bay and dealing with the extra heat. I have seen some rear mount turbo setups that work pretty well, until they are driven in heavy rain, according to the owners. Lots of fun, otherwise. Getting the turbo oiling correct on those takes a bit of finesse.

Watch Bloodmotorsport on YouTube he shows how you can install a super charger on the m113 5.0 with just the s/c pulley belt e55 ecu and a custom heat exchanger. Also shows a turbo kit build