Hello; I build a twin compound supercharger system for the mini 4 cylinder nitro RC engine. I've seen people recently trying to make boost with these mini superchargers, with very little boost being made, all I can do when I watch these video is shake my head, so I decided to show them how it's done! Insane! 3 psi on that scale is monumental! I going bigger should bring even better results. Also, double check all connections for boost leaks. I thought I sorted that problem out, but it was still there. Talking about compound super charging, it's great except you have the superchargers geared the same. It's not going to be a 1:1 ratio on that second supercharger, you'll probably see a little bit of boost gain but it may only be 30-40% gain.