You WILL get more fun per dollar with the 914!
We need more info! Are you building a highly modified race car with unlimited budget? Only have $500 to make a good weekend autocross car?
My 1.7 has a wimpy engine but rides on low profile (50s) tires, is lowered, stiffer rear springs (140lb), and has weltmeister sway bars front and rear. I am saving more $$$ now for a good header, which will be a simple, but not cheap, way to get more out of my engine without taking it apart.