I've made some more simulations with other resonance ratios and noticed that the amplitude of the 5/3 resonance was much lower than the 3/2 and 4/3 resonance .

Further ratios such as 9/7 , 7/5 have also this low value .

Hereunder an overwiew of the results . Depicted is the SMAmax/SMAoriginal of the outer planet .

This is amazing .

The resonances with odd numbers seem remarkable stable .

I also noticed that for this ratios there was no change in eccentricity .