Which more powerful Fiat gasoline engine fits into a Ducato 280 2.0 (XN1T) ?

Hi yours, since my 1990’s Ducato has a chronic lack of performance and extreme thirst, I’d like to know which gasoline engines from the Fiat Stall fit in there. The XN1T has about 75hp and drinks around 18 liters on 100 KM. That must be more powerful and cheaper, right?