I would suggest reading up a bit more on combustion engines and how to increase HP... Not a shot at ya', but its best that you do, in order to prevent wasting time and money with disappointing results. There are no quick pills that'll magically create HP, there are only certain things to do. And the golden rule always applies...
CHEAP/FAST/RELIABLE
put your finger over one word at a time and reveal that you can only have TWO of these at any time...
cheap&fast is not reliable
cheap&reliable is not fast
fast&reliable is not cheap
GOOD LUCK