The OS FS120SP is a four stroke engine with a Roots type supercharger.

I have a 1/8 nitro buggy that I installed an electric supercharger on. I know, I know, I could have gotten a larger engine, more nitro, different tuned pipe, etc etc blah blah blah........ I do not wish to re-hash the merits or demerits of supercharging two stroke engines.

However, part of being a gearhead for me is playing around with, well, gears! So I installed this thing and FWIW, on 20% nitro fuel it required the HS needle to be opened a 1/2 turn richer than normal. It can probably be even richer, but I have not experimented with it any more yet. Without the supercharger, 1/2 turn richer on the needle caused the engine to bog down significantly.

Did it cause this 2-stroke engine to make more power? I dunno, I don't have an engine dyno. It had a lot more 'bark' to it and it certainly seemed to be making more rpm. In any case, it sure did have a positive placebo effect if anything!

And under other circumstances, more fuel being burned means more power.

Regardless, it looks cool, and it does not harm the performance in any way. So it is a fun thing to have and play around with.