Do those two words ever go together? lol. Is it possible for me to do mods which will increase hp and keep the mpg the same or better?

 

What model car do you have?

 

1996 850 turbo manual.

 

Yes it is, it's definitely possible as long as you're not trying for top performance or top fuel economy. Almost every car comes with trade offs in the computer and with some of the engines mass produced parts. With better management and better performing parts it's possible to boost mileage and HP. But they do work against each other when you're trying to get the most of either so that's the trade off.

Most people who slightly modify their cars and get a good tune done on their computers (ARD) have remarked about the better performance and if they keep their foot out of it, better mileage.

 

+1 With Kiss.

 

the downside is that the fuel savings you'll have won't equal to the amount invested in 1 or 2 years. Parts are expensive!