Hasi Tuned .21 Underhead options for new fuel type

New from Hasi Tuned, the engine brand fronted by leading Swiss nitro racer Silvio Hächler, are these two different underhead options for .21 1:8 Onroad & 1:8 GT engines.  They have a different shape especially designed for improved performance with new types of fuel.  They offer a better fitting on Hasi Tuned & O.S. Engines sleeves with one specifically for 25% Nitro content fuel and one for 16% use.

Source: Hasi Tuned [hasituned.eu]