if its an hf then its a 1.3 liter and has like 50 hp, so he might have a problem with that. if its a dx then its a 1.5 with about 75 hp. swapping in an FI motor is a pain but it can be done. other options are putting hot carbs on it, going ITB, or getting a carbed ZC as those go pretty cheap and theyll deliver like 115 hp. if all he needs is a daily driver, tell him to get it. thats cheap as hell and itll get great mileage. an hf will get like 50 mpg in the city

btw i drive an '85 Si and i love it