FAST Injection System: PIAGGIO Solution for ULEV 2T SI Engines 970362
The Hi-Tech Two-Stroke SI engine is finding good appreciation in various fields of vehicle application and the final solution appears to include air assisted direct fuel injection and several solutions are now evaluated by the major world engine manufacturers.
Those solutions anyway are poorly tailored to be fitted on very small engines such as for moped or light scooter applications both for the complications they require, consequentely the costs, and the difficult tuning of low load and idle caused by the very low quantity of fuel per cycle required.
The proposed completely mechanical solution instead does consent with small modifications to the engine, only a new cylinder head is in fact required, to manage very well the engine all over its utilization range.
After general considerations of the philosophy of the system and on the main parameters evaluation, a practical application on a 50cc scooter engine is described. The experimental results show a dramatic improvement on the engine emissions and fuel consumption still maintaining good output performances and low costs.
Finally some considerations about the possible extension of this technology to more sophisticated applications like a multicylinder automotive engine, still offering sound advantages on cost/benefit trade off, are presented.